Day to Day NE NSW / QLD weather

Sandbank

One of Us
Jul 7, 2019
566
4,542
263
Caloundra South and Stanthorpe
51254541408_56a3fc3c24_b.jpg


51255377940_f297806ed7_b.jpg


51253607037_eb1bff83fe_b.jpg


51253606972_4806a24b92_o.png




51255346695_77de59d35d_o.gif




Yes and yes @Rays74
Warm fronts have sometimes passed through SEQ but they're not very common. The thing to remember here is that the MSLP charts you see on the Bureau's website have been traditionally been done by the Bureau's National Meteorological and Oceanographic Centre located at head office in Melbourne. And they've always been notorious in weather circles for their reluctance to draw in fronts, especially warm fronts, even when there's clear evidence of their presence (horizontal and vertical temp gradients, obs, characteristic cloud patterns, etc). It's been a pet hate of mine and some others I know. In fact, you could pretty much safely ignore them as far as identifying whether there's a warm front somewhere or not.
You'll often see warm fronts and occluded fronts marked on charts from many other national weather agencies which cover this area such as the NZ Met Service (although they do tend to overdo it a bit), NOAA's central Pacific branch, etc.

In general, large warm fronts tend to be more common during northern hemisphere winters, especially in the US where it's common to get a warm moist airmass coming up from the Gulf and overrunning a mass of very cold air that's been sitting over the interior. In the southern hemisphere, they're a bit less common but they tend to affect the Southern Ocean more than Australia... although on occasion, they can also affect TAS and VIC.
When warm fronts occur here in SEQ (which are hardly ever marked on the standard MSLP charts), they tend to be on a smaller scale and typically occur when a front/coastal change that's just passed through lags back onto the coast and starts curling around as a localised area of low pressure starts to form on its tip. This can also be in conjunction with an east coast low or a subtropical low that manages to wander just inland of the coast. You'll then sometimes see a frontal structure start to develop from it with a small warm front structure extending out to its east. This front then usually pushes south along the coast as the warm moist air being drawn down the eastern flank of the low runs into the cooler air to the south. When this happens, it's usually only the coastal fringe that gets affected by the front. It looks quite obvious on satpics, obs, and model maps, and as the warm front pushes south, you'll see winds suddenly shift from cool E or SE'lies around to warmer N or NE'ies and a sudden temp rise, sometimes even against the diurnal trend.

The first bunch of images above are some examples of warm fronts that have occurred in the Tasman Sea and the Southern Ocean using EC winds, temps and precip.

The last animation above is a less common example of one a few years ago that occurred in SEQ. This one involved a more localised disturbance near the coast which then extended a warm front out to its east - this subsequently pushed down the coast with an accompanying temp rise and wind shift in the obs at the locations it passed over.
I don't know what it meant unfortunately but I knew it would be smart. ;)
 

Nic Bri

One of Us
Jul 5, 2019
356
2,438
263
Mount Gravatt East
Haha just talking about how warm fronts sometimes occur in SEQ, the fact that they typically extend eastwards out of coastal lows and usually move south along the coast. And that they sometimes show up well in the obs, satpics, and models.

51255115169_b358723c1e_o.jpg


51254573488_02068a4be5_o.jpg


51254400381_ddb5476244_o.gif


Troughs can behave similarly to fronts if the trough is basically an extension of a front i.e. there's somewhat of a temp difference on either side of the trough. But your typical inland trough in the deep summer months is a bit different because they're often pseudo stationary and periodically advance eastwards then retreat westwards again in response to synoptic systems further south and how much inland heating's taking place.

Re fronts, east to west movements are possible but it's uncommon with a warm front and even rarer with a cold front. It's more common with occluded fronts with well-matured cutoff lows where the cold front starts leaning over towards the southeast a lot (negatively tilted), meets up with the warm front, and the resulting occluded front curls right around the low. In these cases, the occluded front can push westwards (on the southern and western flank of the low) especially if the low's moving south or southwest.

A cold front moving directly northward is a bit less rare but still not that common either (northeastward moving cold fronts are much more common). When a northward moving cold front occurs, it's often the last in a series of fronts pivoting up and around an area of deep low pressure passing across to the south of the continent. But when it does occur, the air behind it can be exceptionally cold because of the very southerly fetch behind it.
In contrast, southward moving warm fronts are more the norm than the exception in the southern hemisphere (when warm fronts do occur). The typical scenario involves a warm front extending east out of a low and that front pushing southwards as the warmer northerlies run down the eastern flank of the low.

I've added a few more examples of some past warm fronts in our latitudes. Unfortunately the animation doesn't show the temp contrast pre/post front too well since the colour gradient scale I used back then in Windy was different but you can see those northerlies pushing down into the easterlies and slowly invading the area. It was a lot more noticeable in the temp/wind obs from the AWS's.
Ken you really should charge some kind of subscription to access to the vast meteorological servers you have in your brain! I know it's been said before but it's much appreciated the effort you put both into the local forecasts and the time replying to everyones questions it's such a valuable resource.
 

Ken Kato

One of Us
Jul 13, 2019
3,115
27,750
363
Lol thanks Nic Bri, I think that applies to anyone in general who has a lifelong passion for something though. I think most people who have a passion are keen to talk about it and share it with other people who may be interested. And when people have a passion, it tends to be a lot easier to absorb and store huge amounts of information about it like a sponge. But I'm glad you and others find my comments useful :)
 

Rays74

One of Us
Feb 8, 2020
263
2,944
263
I have another question please LOL

Whats the most northerly point that hail has been recorded in QLD?

I understand hail can't form in tropical or sub tropical regions?

Has hail ever been recorded in NT or Western Australia? I never hear about it.

My friends in the Philippines are shocked to know we can get hail , or even snow near me haha.

Cheers.
 

Ken Kato

One of Us
Jul 13, 2019
3,115
27,750
363
I have another question please LOL

Whats the most northerly point that hail has been recorded in QLD?

I understand hail can't form in tropical or sub tropical regions?

Has hail ever been recorded in NT or Western Australia? I never hear about it.

My friends in the Philippines are shocked to know we can get hail , or even snow near me haha.

Cheers.

That depends on what size of hail we’re taking about @Rays74

The farthest north I’ve seen observations of large hail is Innisfail and inland of the NT Top End coast. But they were only marginally large and large hail is very rare in the tropics. Smaller hail in the tropics isn’t quite as rare as large hail but it’s certainly not common either.
Another striking example was Singapore which got impressive amounts of small hail some years ago due to a very cold pool of air aloft which happened to drift down towards the area. Again, very rare for that to happen.
And yes, WA’s had large hail before as well. I’m not too sure how far north large hail’s been recorded there but further south, Perth had a highly damaging hailstorm some years ago with large hail.

SE QLD and eastern NSW (and occasionally VIC and southwest WA) is in a climatic sweet spot for large hail. The region is just far enough north to get plenty of warm moist air to fuel big storms, close enough to the east coast to get good moisture as well........ and because we’re not in the tropics, we get strong shear from the midlatitudes as well as sufficiently cool air aloft so hailstones don’t have to fall through an excessively deep layer of warm air on the way down and melt before reaching the ground like what usually happens in the tropics such as in north QLD or much of the Philippines.
 

Sandbank

One of Us
Jul 7, 2019
566
4,542
263
Caloundra South and Stanthorpe
That depends on what size of hail we’re taking about @Rays74

The farthest north I’ve seen observations of large hail is Innisfail and inland of the NT Top End coast. But they were only marginally large and large hail is very rare in the tropics. Smaller hail in the tropics isn’t quite as rare as large hail but it’s certainly not common either.
Another striking example was Singapore which got impressive amounts of small hail some years ago due to a very cold pool of air aloft which happened to drift down towards the area. Again, very rare for that to happen.
And yes, WA’s had large hail before as well. I’m not too sure how far north large hail’s been recorded there but further south, Perth had a highly damaging hailstorm some years ago with large hail.

SE QLD and eastern NSW (and occasionally VIC and southwest WA) is in a climatic sweet spot for large hail. The region is just far enough north to get plenty of warm moist air to fuel big storms, close enough to the east coast to get good moisture as well........ and because we’re not in the tropics, we get strong shear from the midlatitudes as well as sufficiently cool air aloft so hailstones don’t have to fall through an excessively deep layer of warm air on the way down and melt before reaching the ground like what usually happens in the tropics such as in north QLD or much of the Philippines.
My first memory of hail was as a 9 yo in Bundaberg when my grandmother left our home in her faded blue Hillman Hunter and had her windscreen was smashed 500m down the road by decent size ice. She was always cranky and the smashed windscreen didn't help her mood.
 

Falling_Droplet

One of Us
Jul 7, 2019
1,780
9,452
363
Ferny Grove, QLD
fernygroveweather.com
Near average temperature from the morning before becoming slightly warm tonight after the temperature rose a little early tonight before falling slowly during the rest of tonight. Dew point have remained moderately low that generally rose slowly in the morning, fell slowly in the afternoon, became stable from the late afternoon becoming stable tonight before rising slowly later tonight.

Low relative humidity in the morning eased to moderately low from the mid morning as the relative humidity fell slowly during the rest of he morning, became stable in the afternoon before rising from later in the afternoon. After temporarily falling the relative humidity rose slowly tonight and have been low or very low. Light W to SW winds in the morning and afternoon with some W to NW winds later in the afternoon and earlier tonight, some calm winds early tonight and W to SW winds during tonight.

Last 24 hours:
temp 2021-6-18.PNG
hum 2021-6-18.PNG
wind dir 2021-6-18.PNG
 

Ken Kato

One of Us
Jul 13, 2019
3,115
27,750
363
51255856368_892b7c43d1_b.jpg


51255659606_d2c3691552_b.jpg


51254937942_ba9b70371b_b.jpg


Above are some recent pics of the remnants of the autumn colours on my birch tree before the leaves dropped (have also included some from my maple tree during its peak before the leaves dropped).
The Southern Hemisphere’s winter solstice is coming up on Monday but it’ll take awhile for daytimes to get that much noticeably longer after the solstice.
 

Snowmaker7

One of Us
Jul 25, 2013
380
1,018
263
Bowral, NSW
Saw quite a few videos on social media yesterday of surprise snow falling in both Guyra and Glen Innes. Had a look at the models and I would have given them about a 5% chance of seeing any sort of frozen precip, nevermind some nice fluffy flakes. Was about 3°C when moisture moved in on PWSs and from what I could see, the humidity was low which would have helped. Will have a dig through what I can find and post the videos if I can.
 

Ken Kato

One of Us
Jul 13, 2019
3,115
27,750
363
Saw quite a few videos on social media yesterday of surprise snow falling in both Guyra and Glen Innes. Had a look at the models and I would have given them about a 5% chance of seeing any sort of frozen precip, nevermind some nice fluffy flakes. Was about 3°C when moisture moved in on PWSs and from what I could see, the humidity was low which would have helped. Will have a dig through what I can find and post the videos if I can.

Funny you mention that @Snowmaker7 ... yesterday morning, I spied with my little eye, a tiny splotch of light snowfall/sleet around Guyra in the 12z run of EC.
Looked very marginal though and a friend of mine who lives there sent me a pic of what landed on his jacket - the flakes were half melted so it was sleet on his jacket rather than pure flakes but I haven’t looked for any other videos people may have taken there which may have showed pure flakes coming down.
 

Snowmaker7

One of Us
Jul 25, 2013
380
1,018
263
Bowral, NSW
Funny you mention that @Snowmaker7 ... yesterday morning, I spied with my little eye, a tiny splotch of light snowfall/sleet around Guyra in the 12z run of EC.
Looked very marginal though and a friend of mine who lives there sent me a pic of what landed on his jacket - the flakes were half melted so it was sleet on his jacket rather than pure flakes but I haven’t looked for any other videos people may have taken there.

Yeah was quite a surprise to me! From the videos I saw on facebook (can be found by searching Guyra posts on facebook) it looked quite wet, apart from one I found which had proper floating flakes. Those sort of somewhat "unforecasted" snow events are the most exciting and interesting ones!
 

Ken Kato

One of Us
Jul 13, 2019
3,115
27,750
363
us_model-en-294-9_modez_2021061712_26_13007_644.png


Yeah was quite a surprise to me! From the videos I saw on facebook (can be found by searching Guyra posts on facebook) it looked quite wet, apart from one I found which had proper floating flakes. Those sort of somewhat "unforecasted" snow events are the most exciting and interesting ones!

Yep @Snowmaker7 they're also golden opportunities for forecast verification and refinement. Above is what EC had. You can see that tiny splotch around Guyra. Do you have the direct link to the one which had the proper floating flakes?
 

Snowmaker7

One of Us
Jul 25, 2013
380
1,018
263
Bowral, NSW
us_model-en-294-9_modez_2021061712_26_13007_644.png




Yep @Snowmaker7 they're also golden opportunities for forecast verification and refinement. Above is what EC had. You can see that tiny splotch around Guyra. Do you have the direct link to the one which had the proper floating flakes?

I honestly didn't even notice that little blotch. Like you said, good chance to refine the models to compensate for these types of systems

Look in the comments of this post, there are a couple of videos of definite, but wet snow/sleet. Unfortunately cant find the good video. Pretty cool!
Guyra snow/sleet FB post link
 

Falling_Droplet

One of Us
Jul 7, 2019
1,780
9,452
363
Ferny Grove, QLD
fernygroveweather.com
Ferny Grove Weather
Date: 19 Jun 2021
Time: 11:55 AM

Min Temp since 9am yesterday: 11.4 C
Max Temp since 9am yesterday: 21.3 C
Min Ground Temp: 8.1 C
Rain since 9am yesterday: 0 mm

Temperature: 18 C
Relative Humidity: 52 %
Dew Point: 7.9 C
MSL Pressure: 1011.9 hPa
Wind Speed: 20 kph - moderate breeze
Wind Direction: W

Present Weather: State of sky generally unchanged during preceding hour
Visibility: 20km to 39km - Very Good Visibility
Cloud Cover: 1/8
Ground State: Ground dry

Notes of yesterday weather - 18/6/21: Sunny in the morning and mostly sunny in the afternoon with some Cu clouds from the morning and Ac clouds in the afternoon. The temperature was generally stable during the early hours before easing back to near average from the morning while the temperature rose from the morning. The temperature became slightly warm in the evening after the temperature rose a little early in the evening before falling slowly during the rest of the evening. Dew point was stable early before rising slowly in the morning that was moderately low, fell slowly in the afternoon, became stable from the late afternoon becoming stable in the evening before rising slowly late in the evening. Relative humidity was generally stable in the early hours before falling in the morning that was very low easing a little to low and then to moderately low from the mid morning as the relative humidity fell slowly during the rest of the morning, became stable in the afternoon before rising from later in the afternoon. After temporarily falling the relative humidity rose slowly in the evening and was low or very low. Calm winds at the start of the day was followed by W to WSW light winds with some SW winds before becoming WSW to SW in the morning and afternoon with some W to NW winds later in the afternoon and early in the evening. Early in the evening were some calm winds and W to SW winds during the evening.

Today: Slightly warm in the early hours easing to near average just before sunrise as the temperature was nearly stable before falling slowly later in the early hours and in the early morning. This morning the temperature have been rising a little slowly and became slightly cool. Dew point have been moderately low that rose slowly in the early hours and this morning which temporarily eased to slightly below average late in the early hours and in the early morning. Low or very low relative humidity in the early hours while the relative humidity rose slowly before falling this morning that eased to slightly below average from the mid morning. Light to moderate and a little gusty at times W to WSW winds from early and W to SW this morning with some WNW and S to SSE winds.
 

Ken Kato

One of Us
Jul 13, 2019
3,115
27,750
363
As at midday, it was a brisk 7.7C in Applethorpe, 11.3C in Toowoomba, and 17.5C in Brisbane but the windchill factor has been making it feel a number of degrees lower than those temps.

Localised power outages around the traps according to Energex (1819 customers on the GC, 119 in the Moreton Bay Regional area, and 2 in the Scenic Rim Regional area).
Some of the stiffer gusts recorded so far today include 63km/hr at Gatton (as well as Cape Moreton), 57km/hr at Toowoomba, and 54km/hr at Brisbane Airport.
 

Kazza47

One of Us
Jul 28, 2019
373
1,881
263
Scary /crazy.


The storm lifted roofs, toppled trees, shattered windows, downed powerlines and sent trampolines flying in the suburb of Papatoetoe at around 8:30am.
A worker was killed when the tornado struck a freight container hub in Wiri Station Road.
Two others were taken to Middlemore Hospital - one is in a moderate condition and the other has minor injuries.
Several containers were toppled by the strong wind.
Ports of Auckland says it operates the site with several other businesses but none of the injured people worked for the company.
It said it is shocked by the freak event and its thoughts are with the people affected.
WorkSafe is investigating the death

News report Video
 

Falling_Droplet

One of Us
Jul 7, 2019
1,780
9,452
363
Ferny Grove, QLD
fernygroveweather.com
Slightly cool temperature during the morning and afternoon becoming cool in the mid to late afternoon as the temperature fell from later in the afternoon. Tonight the temperature eased to near average and have been stable before falling slowly later tonight. Dew point have been moderately low tat rose slowly in the morning, became stable in the afternoon, fell slowly from the mid afternoon before rising slowly later tonight while easing to slightly below average.

Slightly below average relative humidity in the morning and afternoon which after rising slowly from the mid afternoon and became moderately low from early tonight. Light to moderate W to SW winds with some WSW winds since the morning easing to light from the late afternoon and then light W to WSW later tonight with some NNW to WNW winds.

Last 24 hours:
temp 2021-6-19.PNG
hum 2021-6-19.PNG
wind dir 2021-6-19.PNG
wind speed 2021-6-19.PNG
 

Rays74

One of Us
Feb 8, 2020
263
2,944
263
Random question time...

Is there any truth that the Granite Belt region is more susceptible to storms and lightning than anywhere else in QLD?

Is it an old wives' tale that the granite rocks or the iron levels in the ground attract lightning or storms?
The same could be said for the Crows Nest area, I guess?

Is it simply because the terrain and geology is at a greater height, or weather systems get funnelled that direction?

Thanks for any input.
 

Ken Kato

One of Us
Jul 13, 2019
3,115
27,750
363
Random question time...

Is there any truth that the Granite Belt region is more susceptible to storms and lightning than anywhere else in QLD?

Is it an old wives' tale that the granite rocks or the iron levels in the ground attract lightning or storms?
The same could be said for the Crows Nest area, I guess?

Is it simply because the terrain and geology is at a greater height, or weather systems get funnelled that direction?

Thanks for any input.

On average, the Granite Belt does get a fair bit storm action compared to many other parts of QLD but part of that's also because it's within the broader SE QLD/NE NSW region which gets a lot of storms.
In terms of total number of storms, parts of Cape York Peninsula and far northwest QLD tend to get more storms. But the storms in the SE QLD/NE NSW tend to be more severe due to the often stronger shear and the cooler midlevels also help with large hail.
Similar thing with Australia in general. The tropics, mainly in northwestern and far northern parts of Australia have the highest total number of storms on average but typically tend to have less severe storms in terms of large hail, the odd tornado, etc. In contrast, further south there's smaller scale hotspots for storms in SE QLD/NE NSW with a lower total number of storms but a greater proportion of these storms to tend to be severe.

The topography does help with storms in the Granite Belt (and adjoining northern tablelands area in NSW) and the general region is known as one of the preferred thunderstorm genesis areas during typical setups but what often happens is that storms often like to form near the eastern and northeastern parts of the Granite Belt, then get advected east towards SEQ. This is especially noticeable if you've stayed in Stanthorpe for awhile during storm season where you often see the cumulonimbus clouds forming just to the east.

I'm not too familiar with what the iron concentrations in the ground are in the Granite Belt but it's worth remembering that the main components of granite itself (which is obviously dominant in the Granite Belt) are quartz, feldspar, and mica. None of these are rich in iron.

But more importantly, it's also a popular myth that higher iron concentrations in the ground, or metal in general for that matter attracts lightning. Metal simply conducts lightning really well if it's struck by it. It doesn't actually attract it.

P.S. I should add that a lot's also often said about supposed funnelling effects of topography on storms e.g. many people believe storms follow valleys, etc.
But what's often forgotten is the fact that like many weather phenomena, cumulonimbus clouds are 3D rather some sort of flat shallow thing that gets trapped in valleys. They extend 30,000ft up into the sky or higher, and even their bases are often not only at least a few thousand feet above a valley floor, they're also often above the tops of the surrounding mountains i.e. most of the cloud is above the topography, not trapped within it.
Steering winds aloft are the main influence which dictates which way storms move but things like propagation when steering winds are weaker can become more dominant. The role that topography plays with storm movement is more about where they form in the first place and either weakening or strengthening them once they've formed. It's the combination of topography and steering winds aloft that mainly dictate where storms move, not topography alone.
For example, during the classic severe storm setup in SEQ involving strong instability and shear, a SSW steering flow aloft, an ideally timed coastal southerly change, warm moist NNE flow onto the coast, and hotter drier NW flow further inland, storms will often erupt at the triple point where they all converge. And often, the terrain around the Scenic Rim ranges will encourage storms to become severe there, which then start left-moving (veering more towards the N or NNW) and end up hitting the southern, western, and inner suburbs of Brisbane. This is why during that type of setup, those areas tend to cop it more often than other areas, with topography playing an important role but only in conjunction with those other factors - not because storms want to follow valleys.
 
Last edited:

GBerg

One of Us
Jul 28, 2019
68
821
233
Just got back from two weeks in Tassie. It's quite amazing to see rainbows at all times of the day there this time of the year when the sun stays lower to the horizon (it never felt like it got past 9am). We actually had a storm hit Cradle Mountain at 11am at night when it was around 3c. No pics of that as we rode out the insane wind in the campervan. The following pic was taken at Stanley a couple of days later right on Sunset. Its definitely up there with the best rainbows I've witnessed!

007A6538-Pano-Edit-Edit.jpg
 

Falling_Droplet

One of Us
Jul 7, 2019
1,780
9,452
363
Ferny Grove, QLD
fernygroveweather.com
Ferny Grove Weather
Date: 20 Jun 2021
Time: 11:40 AM

Min Temp since 9am yesterday: 9.4 C
Max Temp since 9am yesterday: 19.7 C
Min Ground Temp: 6.1 C
Rain since 9am yesterday: 0 mm

Temperature: 20.6 C
Relative Humidity: 54 %
Dew Point: 10.9 C
MSL Pressure: 1016.6 hPa
Wind Speed: 8 kph - light breeze
Wind Direction: SSW

Present Weather: State of sky generally unchanged during preceding hour
Visibility: 20km to 39km - Very Good Visibility
Cloud Cover: 1/8
Ground State: Ground dry

Notes of yesterday weather - 19/6/21: Sunny. Slightly warm in the early hours easing to near average just before sunrise as the temperature was nearly stable before falling slowly later in the early hours and in the early morning. Slightly cool temperature during the morning and afternoon becoming cool in the mid to late afternoon as the temperature fell from later in the afternoon. In the evening the temperature eased to near average and was stable before falling slowly later in the evening. Dew point was moderately low that rose slowly in the early hours and in the morning which temporarily eased to slightly below average late in the early hours and in the early morning. In the afternoon the dew point became stable in the afternoon, fell slowly from the mid afternoon before rising slowly later in the evening while easing to slightly below average. Low or very low relative humidity in the early hours while the relative humidity rose slowly before falling in the morning that eased to slightly below average from the mid morning. Slightly below average relative humidity in the morning and afternoon which after rising slowly from the mid afternoon became moderately low from the early evening. Light to moderate and a little gusty at times W to WSW winds from early and W to SW from the morning with some WNW and S to SSE winds. Winds eased to light from the late afternoon and then light W to WSW later in the evening with some NNW to WNW winds.

Today: The temperature have been near average that generally fell slowly in the early hours before rising this morning. Dew point was stable from early that was slightly below average, before rising this morning that have remained slightly below average though was briefly close to average. Relative humidity was moderately low while rising in the early hours and early this morning before falling this morning and eased to slightly below average. Light NW to SW winds in the early hours with calm winds at times, W winds from later in the early hours with calm winds at times and became S to SW this morning.
 

Rays74

One of Us
Feb 8, 2020
263
2,944
263
Very good discussion , thanks Ken.

Is there any reason why storms rarely form to the east (say Brisbane City) and move west over Ipswich towards Toowoomba?

I mean a westward moving storm outbreak.

I realise our weather systems usually form west or south west and sweep across SEQ (usually a trough out west causes that?).

I vividly remember the 2011 floods in Toowoomba, as I'm a resident here, and I noticed the flooding rains came from the North East direction.

They call that the "Black Nor-Easter" don't they?

Normally a East Coast Low / tropical system around Bundaberg or Hervey Bay will result in good rains in Toowoomba.

Basically my question is, why do storms (not rain) rarely come from a NE direction in Toowoomba?

Cheers again
 

Ken Kato

One of Us
Jul 13, 2019
3,115
27,750
363
Very good discussion , thanks Ken.

Is there any reason why storms rarely form to the east (say Brisbane City) and move west over Ipswich towards Toowoomba?

I mean a westward moving storm outbreak.

I realise our weather systems usually form west or south west and sweep across SEQ (usually a trough out west causes that?).

I vividly remember the 2011 floods in Toowoomba, as I'm a resident here, and I noticed the flooding rains came from the North East direction.

They call that the "Black Nor-Easter" don't they?

Normally a East Coast Low / tropical system around Bundaberg or Hervey Bay will result in good rains in Toowoomba.

Basically my question is, why do storms (not rain) rarely come from a NE direction in Toowoomba?

Cheers again

It's because the thunderstorm steering winds up in the midlevels are westerlies in our region far more often than from other directions. This is typically the case for much of the world in general outside of the tropics and polar regions. There are some regional differences though due to certain preferred synoptic setups.

But sometimes, steering winds become onshore which then causes storms to come in off the sea, or form just inland of the coast and move further inland. When this happens, it's typically in late summer/early autumn when we sometimes get a deep onshore flow without any westerlies aloft nearby. In saying that, storms in these situations often tend to be less severe near the coast (except for locally intense rainfall with flash flooding) because shear is often weaker and they haven't had much time to grow really big with the less intense heating. Once they get further inland, some can occasionally become severe. It can also happen if there's a midlevel low to our N or NW.

The Jan 2011 flood event was a bit different in that even though there were some storms and they moved further inland, they were mostly embedded in the mass of general rain areas. These storms weren't your usual "hot sunny morning followed by afternoon supercell outbreaks with large hail" type. Their severity was only with respect to the rain rates they caused in conjunction with the rain areas, not large hail or damaging winds.
 

Flowin

One of Us
Ski Pass
Jul 5, 2019
1,917
12,174
363
Pinjarra Hills, QLD
. It's quite amazing to see rainbows at all times of the day there this time of the year when the sun stays lower to the horizon (it never felt like it got past 9am).

007A6538-Pano-Edit-Edit.jpg
interesting you mention that - just the other day when I saw a small part of a rainbow I thought to myself I wonder if there are better chances of rainbows in winter with a lower sun in the sky
 

Flowin

One of Us
Ski Pass
Jul 5, 2019
1,917
12,174
363
Pinjarra Hills, QLD
So we are now a day before the 2021 winter solstice
also just around a hundred or so posts till we hit 20,000 posts for this thread or 400 pages of posts
and around a week to fortnight away from an anniversary of two years since this thread started in early July 2019.... lots of time and forum content in all of that.

so just wondering whether it is a good time to hit reset on this thread sometime in the next week or so and start an annual SEQ NENSW thread?

I had earlier suggested a reset might be needed around spring last year when we were around close to a double century of pages of posts but I also wasn’t keen then cos it was in the midst of what we’d normally expect as our storm season in spring.
Well now looking back I do have to say am I not sure what a normal storm season is anymore
we had a short episode of extraordinary storms like Halloween day hails in spring 2020 and not much else but also the sequences of ‘unseasonal,’ or surprising late Autumn and early Winter storms 2021.
So who knows the ”seasons” that will bring our most entertaining storms in the future ?

I would be interested to know on what others and maybe mods such as @POW Hungry may think about maybe resetting this thread each year
.... and if in agreement is the best time to do it maybe around the winter solistice?
 

Tsunami

One of Us
Jul 6, 2019
754
4,583
263
Cleveland SE QLD
So we are now a day before the 2021 winter solstice
also just around a hundred or so posts till we hit 20,000 posts for this thread or 400 pages of posts
and around a week to fortnight away from an anniversary of two years since this thread started in early July 2019.... lots of time and forum content in all of that.

so just wondering whether it is a good time to hit reset on this thread sometime in the next week or so and start an annual SEQ NENSW thread?

I had earlier suggested a reset might be needed around spring last year when we were around close to a double century of pages of posts but I also wasn’t keen then cos it was in the midst of what we’d normally expect as our storm season in spring.
Well now looking back I do have to say am I not sure what a normal storm season is anymore
we had a short episode of extraordinary storms like Halloween day hails in spring 2020 and not much else but also the sequences of ‘unseasonal,’ or surprising late Autumn and early Winter storms 2021.
So who knows the ”seasons” that will bring our most entertaining storms in the future ?

I would be interested to know on what others and maybe mods such as @POW Hungry may think about maybe resetting this thread each year
.... and if in agreement is the best time to do it maybe around the winter solistice?
I like youre idea.
First thought was January 1st new year thread.
But thats right in the middle of our busy period so could be a bad idea
Perhaps consideration into doing financial year, 1st july to 30th june
 

Rays74

One of Us
Feb 8, 2020
263
2,944
263
Sorry if off topic.
I have a curious mind.

How much does the Jetstream influence our weather in SE QLD?

I understand it can help or hinder airline travel , but can it influence our weather locally?

For example can it induce storms , or add rainfall?

I realise jetstreams move latitude , but does it move in height above Australia?

I think about Mt Everest , because it cannot be climbed if the jetstream is nearby? Wind speeds are too high or bad weather?

Oh , another question can the jetstream spread pathogens or nuclear fallout if it gets that high in the atmosphere?

Thanks
 

Ken Kato

One of Us
Jul 13, 2019
3,115
27,750
363
Sorry if off topic.
I have a curious mind.

How much does the Jetstream influence our weather in SE QLD?

I understand it can help or hinder airline travel , but can it influence our weather locally?

For example can it induce storms , or add rainfall?

I realise jetstreams move latitude , but does it move in height above Australia?

I think about Mt Everest , because it cannot be climbed if the jetstream is nearby? Wind speeds are too high or bad weather?

Oh , another question can the jetstream spread pathogens or nuclear fallout if it gets that high in the atmosphere?

Thanks

Jetstreams can have direct and indirect effects on our weather here. One of its direct effects happens if there's a fairly straight and particularly fast flowing segment (a jetstreak) of a jetstream situated in a particular orientation with respect to our area. Because of an imbalance in flow in different parts of a jetstreak, upper level divergence of air typically occurs in the left entrance region (the NW part) and right exit region (the SE part) of a straight jetstreak. Right entrance region/left exit region if you’re in the northern hemisphere. This upper divergence then encourages air to rise faster in those regions and severe storms become more likely in those areas if there's enough moisture and instability. So naturally, if those areas happen to be over us, it increases severe storm potential.
There's also an argument to be made for the Bernoulli's principle coming into play in areas that lie under the faster moving flow aloft in a jetstream encouraging lower pressures aloft and updrafts below.

The height range in which a jetstream lies also varies depending on latitude, tropopause height (the height at which air stops cooling with height), etc.

There's multiple types of jetstreams but the two main ones are the subtropical jet and polar jet. The subtropical jet is usually a fair bit higher than the polar jet because of the lower latitude and greater height at which the "juncture" of the tropical and midlatitude tropopause occurs.
The polar jet can very occasionally reach us (and also merge with part of the subtropical jet) but it's more common to have the subtropical jet closer to us. The polar jet along with the pseudo stationary polar front is the one that's commonly associated as one of the main mechanisms that dictate the formation, behaviour and movement of midlatitude storm systems and their fronts. It's also typical for the polar jet to act as a dividing line between a much warmer airmass on its equatorward side and a colder airmass on its polar side. So when the jet meanders a lot to the north or south, it often causes much colder or warmer weather in the affected areas.

Re Mt Eeverest, my understanding is that the traditional climbing season there is basically during their mid to late spring because that's when there's usually the best weather. But it's not always good climbing weather even during that period and things can still suddenly change for the worse. Which is why meteorologists are heavily involved in giving climbing weather info to climbers.
Various factors affect the climbing weather there including the monsoon and yes, the subtropical jet can also affect the upper parts of the mountain.
Incidentally I believe a couple of climate scientists with the help of sherpas installed the world's highest automatic weather stations on the upper slopes of Mt Everest a couple of years ago.

And yes, the jetstream can transport anything that can reach those heights and remain suspended in the air for awhile over big distances. But the longer anything remains in the jetstream, the more dispersed it'll be when it eventually does fall out of it.
It's not just jetstreams themselves that can act as a transport mechanism though. Any strong upper level winds in general can do that.

There's lots of websites that can answer your questions and satisfy your curious mind if you're interested. Here's one of many (despite the jetstream part in the URL, it covers all sorts of meteorological stuff, not just jetstreams): https://www.weather.gov/jetstream/
 

POW Hungry

Old n' Crusty
Moderator
Ski Pass
May 28, 2000
23,024
36,847
1,063
Eastern Burbs of Sydney
So we are now a day before the 2021 winter solstice
also just around a hundred or so posts till we hit 20,000 posts for this thread or 400 pages of posts
and around a week to fortnight away from an anniversary of two years since this thread started in early July 2019.... lots of time and forum content in all of that.

so just wondering whether it is a good time to hit reset on this thread sometime in the next week or so and start an annual SEQ NENSW thread?

I had earlier suggested a reset might be needed around spring last year when we were around close to a double century of pages of posts but I also wasn’t keen then cos it was in the midst of what we’d normally expect as our storm season in spring.
Well now looking back I do have to say am I not sure what a normal storm season is anymore
we had a short episode of extraordinary storms like Halloween day hails in spring 2020 and not much else but also the sequences of ‘unseasonal,’ or surprising late Autumn and early Winter storms 2021.
So who knows the ”seasons” that will bring our most entertaining storms in the future ?

I would be interested to know on what others and maybe mods such as @POW Hungry may think about maybe resetting this thread each year
.... and if in agreement is the best time to do it maybe around the winter solistice?
Sounds fine with me.
An annual thread is a good way to archive things, climatically.
On calendar year (Jan-Dec) would make it easy to reference IMO.

But up to you guys.
 

Falling_Droplet

One of Us
Jul 7, 2019
1,780
9,452
363
Ferny Grove, QLD
fernygroveweather.com
The temperature have been near average since the morning that was briefly slightly warm in the mid afternoon with the temperature a little variable on the mid to late afternoon. Dew point eased back to near average from the late morning that rose in the morning and afternoon and generally fell slowly from the mid afternoon. Relative humidity remained slightly below average in the morning, afternoon and early tonight that fell slowly later in the morning and in the afternoon before rising from the mid afternoon. Light S to SW winds in the morning and afternoon with some WSW winds, SSE to SSW in the late afternoon before mostly calm winds tonight with brief WSW winds late tonight.

Last 24 hours:
temp 2021-6-20.PNG
hum 2021-6-20.PNG
wind dir 2021-6-20.PNG
 

Ken Kato

One of Us
Jul 13, 2019
3,115
27,750
363
1624224623903.png


1624224638977.png


Excellent info about jetsteams and cheers for the link.

Why are jetsteams (and warm fronts) not shown on synoptic charts?

Do such things appear on aviation charts instead?

Synoptic MSLP charts are mainly meant to represent surface systems such as lows, fronts and isobars rather than anything happening in the upper levels. But Weatherzone do choose to display jetstreams on some of their charts.

I don't know why the NMOC (part of the Bureau) who do the synoptic charts have been so reluctant to draw in warm fronts. They have gotten a bit better and show them more than they used to but still, the 4-day so-called "colour" small MSLP charts on the Bureau's website are a relic from the early 2000's/1990's and the website itself hasn't been updated for over a decade now. It's quite embarrassing to be honest, even compared to those from third world countries many of whom have flashy user-friendly websites these days in comparison. The outdated website's been a pet peeve among even quite a few frontline workers in the Bureau itself. It makes quite a number of people in the public flock to social media weather pages for more info or better-looking graphics. If you want MSLP charts that are really basic, old and not-too-easy on the eyes, go to the Bureau's site. If you don't, I'd recommend other sources.

Jetstreams, fronts and other things such as clear air turbulence, cumulonimbus heights, tropopause heights, etc are shown on certain aviation weather products. The 1st example above is of an aviation forecast significant weather chart for the 10,000 to 25,000ft height range and the 2nd one's for 25,000 to 63,000ft. The subtropical and polar jets are the thick black curvy lines in the 2nd chart. The solid black half-triangles along the jetstreams represent each 50kt increment in the jetstream's flow speed while the thin black lines next to them represent 10kt increments. The FLxx labels on the jetstreams are the heights of the core of that jetstream e.g. FL370 is 37,000ft. The green cloud-like outlines represent areas of forecast significant cloud in those height ranges that could affect flights via turbulence or icing. The dashed lines are areas of clear air turbulence.
 

PeteJ

One of Us
Jul 5, 2019
453
2,693
263
Toowoomba
but still, the 4-day so-called "colour" small MSLP charts on the Bureau's website are a relic from the early 2000's/1990's and the website itself hasn't been updated for over a decade now. It's quite embarrassing to be honest, even compared to those from third world countries many of whom have flashy user-friendly websites these days in comparison. The outdated website's been a pet peeve among even quite a few frontline workers in the Bureau itself. It makes quite a number of people in the public flock to social media weather pages for more info or better-looking graphics. If you want MSLP charts that are really basic, old and not-too-easy on the eyes, go to the Bureau's site. If you don't, I'd recommend other sources.
I think it reflects Australians and especially politicians' attitude to science generally. If you can't dig it out of the ground and sell it it is of no value. How cynical Eh!!
But there is the other problem. Most of the time the weather pattern in Australia is so boring (and as I have posted above), it is just not worth the effort to go beyond the BOM's current 4-day charts.
 

Rays74

One of Us
Feb 8, 2020
263
2,944
263
Amazing knowledge you have Ken.

Really appreciate you sharing and putting the info into layman terms

It's difficult to Google answers like this.

Those charts really illustrate what I was wanting to know.

Big thanks.


Heavy dew last night , and very light frost in Toowoomba City early this morning.
 

Falling_Droplet

One of Us
Jul 7, 2019
1,780
9,452
363
Ferny Grove, QLD
fernygroveweather.com
Ferny Grove Weather
Date: 21 Jun 2021
Time: 9:20 AM

Min Temp since 9am yesterday: 8.8 C
Max Temp since 9am yesterday: 23.2 C
Min Ground Temp: 5.5 C
Rain since 9am yesterday: 0 mm

Temperature: 17.6 C
Relative Humidity: 64 %
Dew Point: 10.7 C
MSL Pressure: 1021.7 hPa
Wind Speed: 5 kph - light air
Wind Direction: S

Present Weather: State of sky generally unchanged during preceding hour
Visibility: 20km to 39km - Very Good Visibility
Cloud Cover: 0/8
Ground State: Ground dry

Notes of yesterday weather - 20/6/21: Sunny with some Cu clouds and partly cloudy with Cu clouds from the mid afternoon. The temperature was near average from early that generally fell slowly in the early hours that was briefly slightly warm in the mid afternoon with the temperature a little variable in the mid to late afternoon. Dew point was stable from early that was slightly below average, before rising in the morning that remained slightly below average though was briefly close to average. Dew point eased back to near average from the late morning that rose in the morning and afternoon and generally fell slowly from the mid afternoon. Relative humidity was moderately low while rising in the early hours and early in the morning before falling in the morning and eased to slightly below average. Relative humidity remained slightly below average through the afternoon and early evening that fell slowly later in the morning and in the afternoon before rising from the mid afternoon. Light NW to SW winds in the early hours with calm winds at times, W winds from later in the early hours with calm winds at times and became S to SW in the morning and afternoon with some WSW winds. Light SSE to SSW winds in the late afternoon before mostly calm winds in the evening with brief WSW winds late in the evening.

Today: The temperature was generally stale in the early hours and early morning that was close to average though was briefly slightly cool at the start of the day and early this morning. Late in the early hours the temperature rose a little before falling afterwards. The temperature have remained near average while rising this morning. Dew point have been near average that fell very slowly from early though the dew point rose a little late in the early hours. Near average relative humidity at the start of the day became slightly below average later in the early hours and during this morning that was generally stable in the early hours, which temporarily dipped later in the early hours before falling during this morning. Mostly calm winds early and early this morning with some SSE to W winds at times before light S to SSW winds this morning.
 

Ken Kato

One of Us
Jul 13, 2019
3,115
27,750
363
Just got back from two weeks in Tassie. It's quite amazing to see rainbows at all times of the day there this time of the year when the sun stays lower to the horizon (it never felt like it got past 9am). We actually had a storm hit Cradle Mountain at 11am at night when it was around 3c. No pics of that as we rode out the insane wind in the campervan. The following pic was taken at Stanley a couple of days later right on Sunset. Its definitely up there with the best rainbows I've witnessed!

007A6538-Pano-Edit-Edit.jpg

Great shot and awesome landscape for the setting too.
 

Ken Kato

One of Us
Jul 13, 2019
3,115
27,750
363
LP sitting near North Island NZ. I'm guessing the genesis might be the same as the winter tornadoes (terminology?) that hit Perth most winters with onshore arrival of a cold front.

I wasn't keeping a close eye on the setup but from what I noticed, there was a decent low to the NW of the North Island with plenty of warm air advection coming into its southeastern quadrant (the region where the most dynamic weather tends to occur). Would've been plenty of low level shear there as well although I didn't check that aspect.
 
Remove ads with a
Ski Pass

Log in

or Log in using
Learn how membership works on these forums
Remove ads with a
Ski Pass