Rain and storm for Cpt

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Gordon_R said:
I'd take those figures with a pinch of salt (and not just because the forecast can change). Whenever you see rain and snow in the same 6 hour period, it usually ends up as slush. When temperatures fluctuate over a period, the snow is unlikely to accumulate to any great depth. Wed 21st is definitely looking like the best day for the SW-Cape.
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Tuesday snow yes, but temp drops on wed - Wed temps esp afternoon are looking all below zero so maybe 10cm of snow - btw have updated my post with SA snow forcast map too
 
Rocco1 said:
Tuesday snow yes, but temp drops on wed - Wed temps esp afternoon are looking all below zero so maybe 10cm of snow - btw have updated my post with SA snow forcast map too
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IMO snow doesn't accumulate much during the afternoon, overnight is the best time. Coastal areas also seem to get less cold due to ocean influence, inland is often better. Keep an eye on the freezing level, 1000m is marginal for Table Mt, 900m is better, and 800m is best (but very rare). Also remember this is still 5 days away...

P.S. Wind chill affects human comfort levels, but has no effect on the freezing or melting of water.
 
Gordon_R said:
IMO snow doesn't accumulate much during the afternoon, overnight is the best time. Coastal areas also seem to get less cold due to ocean influence, inland is often better. Keep an eye on the freezing level, 1000m is marginal for Table Mt, 900m is better, and 800m is best (but very rare). Also remember this is still 5 days away...

P.S. Wind chill affects human comfort levels, but has no effect on the freezing or melting of water.
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Haha, thanks for the reminder. Wind chill was just to scare the adventure lovers that decide to go up the mountain in the middle of a storm. Yeah ground temp is often above zero as the first few centimetres of snow melt, and can freeze at night forming an ice layer, and only then do you get good accumulation. freezing level 800m at De Toits peak, and forcast to be 750m at Matroosberg.
N1 Hex river pass tops out at 950m.

Obviously anything can change between now and then, a slight shift in the wind more westerly, or a delayed switch to the south westerlies could all change temps a few degrees up and move snow line much higher.
1200m level is nearly guaranteed though, and those areas are likely to actually get snowed in/cut off on Wed evening.
Koubokerveld for instance is +-20cm (current forcast)
 
Rocco1 said:
Haha, thanks for the reminder. Wind chill was just to scare the adventure lovers that decide to go up the mountain in the middle of a storm. Yeah ground temp is often above zero as the first few centimetres of snow melt, and can freeze at night forming an ice layer, and only then do you get good accumulation. freezing level 800m at De Toits peak, and forcast to be 750m at Matroosberg.
N1 Hex river pass tops out at 950m.

Obviously anything can change between now and then, a slight shift in the wind more westerly, or a delayed switch to the south westerlies could all change temps a few degrees up and move snow line much higher.
1200m level is nearly guaranteed though, and those areas are likely to actually get snowed in/cut off on Wed evening.
Koubokerveld for instance is +-20cm (current forcast)
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Recent model runs have weakened somewhat, although this is still going to be a significant weather event. Rainfall for CT is likely to be around 25mm, which is relatively low for a cold-front and amounts further inland are trending lower.

The predicted freezing-level for Table Mt is now expected to be around 1150m, which is marginal for snow. Heavy falls are likely over the Western Cape mountains, and over large parts of the Eastern Cape, but not as far inland over the Karoo as previously suggested.

Later in the week the system will have a significant impact on the southern Drakensberg and parts of KZN. It will also become rather cold further north.
 
air said:
For those in the know, where does the water end up when TWK overflows?
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Pretty much everything north and east of Sir Lowry's Pass flows into the Breede River. Nice map here:

Map-of-the-Breede-River-Catchment.png
 
Storm has weekened even more - "massive" snowfall is gonna turn into a damp squid. Freezling level at 1150m now and much less precipitation. should get snowfall down to 1000m in places but prob wont settlel on TM (1cm only now) inland areas at 1200m should receive some snow in ceres region.
It looks the HP cell to the west is ridging in and has blocked the storm and pushed it much further south.
(wed midday forcast)
1626650945331.png
 
Rocco1 said:
Storm has weekened even more - "massive" snowfall is gonna turn into a damp squid. Freezling level at 1150m now and much less precipitation. should get snowfall down to 1000m in places but prob wont settlel on TM (1cm only now) inland areas at 1200m should receive some snow in ceres region.
It looks the HP cell to the west is ridging in and has blocked the storm and pushed it much further south.
(wed midday forcast)
View attachment 1110156
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Those kind of fluctuations in the models were exactly what I suggested last week. Exceptional long-range forecasts have a lot of uncertainty, and seldom unfold as expected.

It's still going to be rather cold, with yr.no showing a maximum temperature of 12C for CT on Wed 21st: https://www.yr.no/en/forecast/daily...rica/Western Cape/City of Cape Town/Cape Town

The good news is that PE should get some rain this week...
 
Fairly constant showers from 7 until about 10ish this am, rain stopped and cloud cover has now partially cleared and even a spot of sunlight coming through.....

Tomorrow however, looks like a different story.
Heavy rain most of the day, and v cold.
 
Was raining hard and then just stopped....
Blue skies replaced cloud cover...looks like the forecast for rain the entire day won't materialise.
 
MirageF1 said:
Was raining hard and then just stopped....
Blue skies replaced cloud cover...looks like the forecast for rain the entire day won't materialise.
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The satellite view shows a significant gap in the clouds, with a 3rd front this afternoon bringing further showers. The rain in CT will be less than the Overberg, but this system ain't over yet...

Edit: Sudden downpour in Kenilworth at 10:15. Rumble of thunder too...
 
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Eid is on a Wednesday for a change, so it'll be poring today.
 
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