The 'Massive' Gauteng Weather and Storm Warning Thread! The Sequel

[RaptorSA]

She's coming...
Dammit, should have just taken some leave days next week.

 

[NR7]

Google's 3 days of snow vs Accuweather's only rain. Let's see who's right

 

[Gordon_R]

She's coming...
Dammit, should have just taken some leave days next week.

View attachment 1928054

The satellite photo only shows the clouds that have already formed. The preliminary cold-front is actually rather weak. What comes next is much more powerful, but harder to see. A large trough of cold upper air is pushing in behind the front, and will extend over most of SA by Mon 10th. Then we will see the development of a cutoff-low, with all the weird weather across the interior of the country.

I don't have the snappy charts that the forecasters put out, but this gives some idea of developments by Mon 10th, and Tues 11th:

 

[Heisenborg]

The satellite photo only shows the clouds that have already formed. The preliminary cold-front is actually rather weak. What comes next is much more powerful, but harder to see. A large trough of cold upper air is pushing in behind the front, and will extend over most of SA by Mon 10th. Then we will see the development of a cutoff-low, with all the weird weather across the interior of the country.

I don't have the snappy charts that the forecasters put out, but this gives some idea of developments by Mon 10th, and Tues 11th:
View attachment 1928135
View attachment 1928136
View attachment 1928137

Did somebody say cut off low. Always exciting

 

[RaptorSA]

The satellite photo only shows the clouds that have already formed. The preliminary cold-front is actually rather weak. What comes next is much more powerful, but harder to see. A large trough of cold upper air is pushing in behind the front, and will extend over most of SA by Mon 10th. Then we will see the development of a cutoff-low, with all the weird weather across the interior of the country.

I don't have the snappy charts that the forecasters put out, but this gives some idea of developments by Mon 10th, and Tues 11th:
View attachment 1928135
View attachment 1928136
View attachment 1928137

If I had next week off I would have likely visited some family in Ermelo.
I see there's a good chance for some decent snow there.... would have been nice to see snow again.

 

[Heisenborg]

Ready your boats!!!

 

[AnimateX]

Ready your boats!!!

Or gloves to build snowmen. I honestly don't know what to expect anymore haha.

 

[Segg]

You can very clearly see the cold air displacing the warm air ahead of the front on the satellite image this evening but I’m using my tablet this evening so I can’t post it…

What I can post is the high level significant weather chart with a very interesting jet stream showing it over effectively 10 000ft thick and the tropopause being very low to the south of the jet stream as indicated by the 280L

 

[Speedster]

I mean maybe for the kids to play with I did use my day off today to fix my roofs waterproofing at least

View attachment 1927518

What language is this?

 

[wingnut771]

What language is this?

Seems Scandinavian:





Is this their summer temps?

Is the OP longing to be back in GP?

Seeing that Scandinavia is allowed, just want to let you guys know that I'm still in t-shirt and shorts in dbn, it sure as hell doesnt "feel like 14c":

 

[Gordon_R]

You can very clearly see the cold air displacing the warm air ahead of the front on the satellite image this evening but I’m using my tablet this evening so I can’t post it…

What I can post is the high level significant weather chart with a very interesting jet stream showing it over effectively 10 000ft thick and the tropopause being very low to the south of the jet stream as indicated by the 280L

View attachment 1928405

I miss those sigwx charts, but they have long become subscription only. The aviation servers were very busy (I was just looking at Metars and TAFs), with many users downloading such charts! Flight planning during this event would be extremely challenging...

There are multiple ways of visualising such complex 3D weather systems, but one of the more visual ones is the CPC GFS charts for Southern Africa. Various levels and parameters are available (unfortunately each is separate), with the 500hPa temperature being the most interesting. Source: https://www.cpc.ncep.noaa.gov/products/international/cpci/data/00/fcsts_safrica.shtml

The cold core upper trough is shown pushing far inland over SA, and will soon 'split' into a cutoff low, persisting over several days:

 

[wingnut771]

You can very clearly see the cold air displacing the warm air ahead of the front on the satellite image this evening but I’m using my tablet this evening so I can’t post it…

What I can post is the high level significant weather chart with a very interesting jet stream showing it over effectively 10 000ft thick and the tropopause being very low to the south of the jet stream as indicated by the 280L

View attachment 1928405

Its not clear to all those who have forgotten their education from high school geography. Please decode it for us.

I took geography up to matric ('96) and this is still Greek to me.

 

[wingnut771]

I miss those sigwx charts, but they have long become subscription only. The aviation servers were very busy (I was just looking at Metars and TAFs), with many users downloading such charts! Flight planning during this event would be extremely challenging...

There are multiple ways of visualising such complex 3D weather systems, but one of the more visual ones is the CPC GFS charts for Southern Africa. Various levels and parameters are available (unfortunately each is separate), with the 500hPa temperature being the most interesting. Source: https://www.cpc.ncep.noaa.gov/products/international/cpci/data/00/fcsts_safrica.shtml

The cold core upper trough is shown pushing far inland over SA, and will soon 'split' into a cutoff low, persisting over several days:
View attachment 1928414View attachment 1928415
View attachment 1928416View attachment 1928417View attachment 1928418View attachment 1928419

Yours at least has colours and stuff, either you followed your "masters" instructions properly or you didn't and just did the bare minimum like post #3728 even though I'm trying to roast it like how its done these days, like a chinese package all in one boat cruise:

 

[wingnut771]

Ok. As a naturalised natalian (), that is actively experiencing rain (on the berea), can they do me a favour and use their googlefu skills (calling @Lupus) and find the kzn weather thread (its so rare because people only post when the world is ending), and because its so rare, its hard to find it again (post count/social media presence) because the billionaires have orders from the new world order we will own nothing andf be happy crowd (at least for me, I have to use actual "google" which ends up doing the job instead of using mybb search (china shill!) where is keeps telling me...... Reading back what I said, I acknowledge the message so far is complete bull ****, whats even more bullshit is the fact that you blonde hair **** hasnt left the country yet and are still shilling for them.

 

[Gordon_R]

Its not clear to all those who have forgotten their education from high school geography. Please decode it for us.

I took geography up to matric ('96) and this is still Greek to me.

Aviation sigwx charts take about a week's training to understand properly. They are not meant for public consumption. I am not a pilot, but did the course online, because the charts are a useful concise summary for weather nerds. This is the upper level chart (above 5km). There is also a medium/low level chart (showing snow and freezing levels).

Trying to decode this one chart for you would take about a week's worth, to translate into layman's language. You don't know what you don't know. The units are all mixed up, with heights in hundreds of feet (aka flight levels), wind speeds in knots, and multiple abbreviations.

Wind directions are shown by the solid black lines, which are the peak/core of the jet. Speeds are measured in multiples of ten, with a triangle for 50 and a tick for each extra 10.

This is a single fixed time snapshot forecast a few hours ahead, for flight planning. Charts are issued every 3 hours, and valid for 9 to 18 hours ahead. Digital versions are also available.

Jet stream winds affect fuel consumption. Turbulence (CAT) affects passenger comfort. CBs are cumulonimbus (thunderstorms) that no aircraft can fly into, and must be avoided by radar vectoring (ground based or on-board). The risk of flying into hail should be self evident. The cloud top levels for various areas are shown, as some storms can be flown over (subject to maximum altitudes), while others need to be avoided completely. Cloud base levels are not shown in this chart, but continuous cloud thickness is implied by XXX below the top levels.

No light aircraft should fly anywhere near this system, and aircraft that do fly must be instrument rated for flying in clouds, and equipped with anti-ice heating on the engines, wings, and flight control surfaces. Even well equipped aircraft may need to divert, reroute, or fly at different altitudes.

Isolated single storms are common in summer, and can be planned around. Winter is normslly quiet over the interior of SA. This event is both unusual, widespread, and severe.

 

[wingnut771]

Aviation sigwx charts take about a week's training to understand properly. They are not meant for public consumption. I am not a pilot, but did the course online, because the charts are a useful concise summary for weather nerds. This is the upper level chart (above 5km). There is also a medium/low level chart (showing snow and freezing levels).

Trying to decode this one chart for you would take about a week's worth, to translate into layman's language. You don't know what you don't know. The units are all mixed up, with heights in hundreds of feet (aka flight levels), wind speeds in knots, and multiple abbreviations.

Wind directions are shown by the solid black lines, which are the peak/core of the jet. Speeds are measured in multiples of ten, with a triangle for 50 and a tick for each extra 10.

This is a single fixed time snapshot forecast a few hours ahead, for flight planning. Charts are issued every 3 hours, and valid for 9 to 18 hours ahead. Digital versions are also available.

Jet stream winds affect fuel consumption. Turbulence (CAT) affects passenger comfort. CBs are cumulonimbus (thunderstorms) that no aircraft can fly into, and must be avoided by radar vectoring (ground based or on-board). The risk of flying into hail should be self evident. The cloud top levels for various areas are shown, as some storms can be flown over (subject to maximum altitudes), while others need to be avoided completely. Cloud base levels are not shown in this chart, but continuous cloud thickness is implied by XXX below the top levels.

No light aircraft should fly anywhere near this system, and aircraft that do fly must be instrument rated for flying in clouds, and equipped with anti-ice heating on the engines, wings, and flight control surfaces. Even well equipped aircraft may need to divert, reroute, or fly at different altitudes.

Isolated single storms are common in summer, and can be planned around. Winter is normslly quiet over the interior of SA. This event is both unusual, widespread, and severe.

tldr
decode:

I'm sure if I was tortured enough (at gwantanomo bay, geneva convention is just happy feelings on paper, never in the history of human kind have we won any wars on feelings) and my life was on the line then I feel my subconscious would deliver something I absorbed during geography class as this map is not completely foreign to me, but still foreign in the sense of trying to help with homework after 30 years, but unfortunately for you guys my life isn't under threat so my subconscious is doing nothing worth writing home about.

tldr version: I should know this but I can't remember.

*edit edit: I actually started reading it and sort of remember the triangle is 50 and each line is 10, unfortunetly this is one of those things that I absorbed but have never needed it in my entire life, just like 100% of the other things I absorbed in school but proved absolutely useless in real life.

edit edit: dont know what the wavy lines are/mean.

 

[Lupus]

Ok. As a naturalised natalian (View attachment 1928421), that is actively experiencing rain (on the berea), can they do me a favour and use their googlefu skills (calling @Lupus) and find the kzn weather thread (its so rare because people only post when the world is ending), and because its so rare, its hard to find it again (post count/social media presence) because the billionaires have orders from the new world order we will own nothing andf be happy crowd (at least for me, I have to use actual "google" which ends up doing the job instead of using mybb search (china shill!) where is keeps telling me...... Reading back what I said, I acknowledge the message so far is complete bull ****, whats even more bullshit is the fact that you blonde hair **** hasnt left the country yet and are still shilling for them.

No dedicated thread

Thread 'The end is nigh in Durban.'

Oct 11, 2022

So, giant surge just flew through Durban while there is 30 degrees wind blowing about and a storm brewing.

No idea where to post, but there was a 5 second surge and a ton of areas are out, people are reporting a giant blue power flare in the distance. Wind has picked up we had all the lights flickering for quite some time, while most devices simple cut off with quite a noise.

Was nice knowing you guys

• ghostRgg
• Replies: 345
• Forum: Eskom and Electricity: Load Shedding

• 
• 
• 

Closest you'll find

 

[TheOracle]

No dedicated thread

Thread 'The end is nigh in Durban.'

Oct 11, 2022

So, giant surge just flew through Durban while there is 30 degrees wind blowing about and a storm brewing.

No idea where to post, but there was a 5 second surge and a ton of areas are out, people are reporting a giant blue power flare in the distance. Wind has picked up we had all the lights flickering for quite some time, while most devices simple cut off with quite a noise.

Was nice knowing you guys

• ghostRgg
• Replies: 345
• Forum: Eskom and Electricity: Load Shedding

• 
• 
• 

Closest you'll find

Thread '[KZN] SA Weather Service issues heavy rain warning'

Nov 10, 2017

SA Weather Service issues heavy rain warning
https://highwaymail.co.za/275866/sa-weather-service-issues-heavy-rain-warning/

STORMY weather is expected in the eastern parts of South Africa today, Friday, 10 November. The South African Weather Service has issued two weather warnings of possible heavy rainfall which it says may lead to flash flooding over the KZN coast and adjacent interior from noon to around 11pm this evening. A second warning of possible severe thunderstorms with strong winds and a possibility of hail has also been issued for north-western KZN from 1pm to...

• DanDango
• Replies: 2,901
• Forum: News and Current Affairs

• 

 

[Lupus]

Thread '[KZN] SA Weather Service issues heavy rain warning'

Nov 10, 2017

SA Weather Service issues heavy rain warning
https://highwaymail.co.za/275866/sa-weather-service-issues-heavy-rain-warning/

STORMY weather is expected in the eastern parts of South Africa today, Friday, 10 November. The South African Weather Service has issued two weather warnings of possible heavy rainfall which it says may lead to flash flooding over the KZN coast and adjacent interior from noon to around 11pm this evening. A second warning of possible severe thunderstorms with strong winds and a possibility of hail has also been issued for north-western KZN from 1pm to...

• DanDango
• Replies: 2,901
• Forum: News and Current Affairs

• 

That's going back some, but that as well

 

[Gordon_R]

tldr
decode:
View attachment 1928422View attachment 1928423View attachment 1928424View attachment 1928425View attachment 1928426View attachment 1928427
I'm sure if I was tortured enough (at gwantanomo bay, geneva convention is just happy feelings on paper, never in the history of human kind have we won any wars on feelings) and my life was on the line then I feel my subconscious would deliver something I absorbed during geography class as this map is not completely foreign to me, but still foreign in the sense of trying to help with homework after 30 years, but unfortunately for you guys my life isn't under threat so my subconscious is doing nothing worth writing home about.

tldr version: I should know this but I can't remember.

*edit edit: I actually started reading it and sort of remember the triangle is 50 and each line is 10, unfortunetly this is one of those things that I absorbed but have never needed it in my entire life, just like 100% of the other things I absorbed in school but proved absolutely useless in real life.

edit edit: dont know what the wavy lines are/mean.

The wavy lines are cloud/airmass boundaries. Each has broadly the same hazard levels (not sure how they define these). The cloud types and altitude limits apply to each airmass boundary, as severity and frontal boundaries vary. These charts are not detailed forecasts, but broad-scale planning aids, though certainly interesting for weather nerds.

Edit: The two parallel bars on the jet stream are not super important, something to do with speed increase or decrease. Sigwx charts cover quite large regions, Area C Is most of Europe and Africa. This covers the majority of N/S flights in one map, but necessarily a summary only.

Edit #2: The chart format will be phased out in 2027/8, transitioning to digital format (though both are likely to persist for a while).

Here is a short reference, with a link to a proper PDF reference: https://skybrary.aero/articles/significant-weather-sigwx-forecasts

SIGWX charts highlight en-route hazards such as:
Jet streams (winds greater than 80 kts)
Turbulence
Icing
Cumulonimbus clouds
Volcanic ash
Tropical cyclones