Rain and storm for Cpt

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Felt threatening all day so far here in S Subs, thick low, cloud cover and fresh to moderate wind but no rain... stopped quite early this am, around 6ish.
 
MirageF1 said:
Felt threatening all day so far here in S Subs, thick low, cloud cover and fresh to moderate wind but no rain... stopped quite early this am, around 6ish.
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Low cloud itself does not mean rain (sometimes drizzle). Precipitation usually requires a deep layer of moisture, and some instability. Last night a compact cold-core upper trough passed over CT, and that was the cause of most of the activity.

By contrast, rain over the interior of SA is more often caused by surface heating, which is much rarer around Cape Town. The South Atlantic High Pressure usually brings a layer of descending dry air, which produces an inversion layer, and negative instability.

To get a full picture of a cutoff-low, you have to look at multiple parameters simultaneously (moisture, winds, temperatures and instability). This is why model rainfall charts are quite helpful (more than surface observations and satellite images). This is also why some sectors of the COL can be 'dry', if only a few of the parameters are favourable.

Edit: This 500hPa temperature chart shows the upper instability at 8am on Sun 5th:

500mb_tmp_030[20211205_0600_crop].gif

See: https://www.cpc.ncep.noaa.gov/products/international/cpci/data/00/gfs_500mb_tmp_safrica.html

If you look at the moisture charts (and satellite images), you can see some overlap, but they do not coincide exactly: https://www.cpc.ncep.noaa.gov/products/international/cpci/data/00/gfs_pwat_safrica.html

Source: https://www.cpc.ncep.noaa.gov/products/international/cpci/data/00/fcsts_safrica.shtml
 
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Gordon_R said:
Reports of some heavy rain and isolated flooding in parts of the Garden Route:
www.news24.com

Weather warning for Western Cape after downpours cause flooding, road closures | News24

Roads have been closed, houses damaged, and one person had to be rescued from a low bridge, after the Western Cape was lashed by strong winds and heavy rain.
www.news24.com www.news24.com
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I've got family who own a farm about 100km east of Beaufort West in the Karoo, they've had the heaviest rainfall in years in the past 3 days. Farms in the area are completely flooded making it very difficult to get out of the area.
 
Gordon_R said:
Reports of some heavy rain and isolated flooding in parts of the Garden Route:
www.news24.com

Weather warning for Western Cape after downpours cause flooding, road closures | News24

Roads have been closed, houses damaged, and one person had to be rescued from a low bridge, after the Western Cape was lashed by strong winds and heavy rain.
www.news24.com www.news24.com
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That's an OLD video they used with that article ... why oh why bullshit the people like that. A video of what actually happened this weekend would have been better. :mad:
 
264832549_4599224720193859_8195577301999319382_n.jpg

Karatar Bridge in Knysna overflowing. some flooding in George, and 2 passes in the KC closed.
 
DWPTA said:
I know it's the wrong thread and province, but anyone seen the vids of Waterval Boven. Never seen it gushing so much water
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My family had a farm 6km upstream from that waterfall until quite recently. About 10 years ago the flooding was way worse, it washed away a concrete bridge crossing the river, and significantly altered the river itself, the latest pictures and videos aren't really anything crazy....

What is crazy is that people are walking to that waterfall as the trek is seriously dangerous from a crime point of view. You usually park after exiting the boven tunnel, then walk through the old one next to it, where gangs typically wait for you. Last time I went to see the waterfall was by air.

Capture.JPG
 
MirageF1 said:
A few mm of rain forecast around midday, but I'm sceptical there'll be any... would be nice though.
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Another weak cold-front passing just south of CT today. The forecasts are hard to determine in this kind of situation: yr.no shows 0.1mm, so don't expect too much, but prepare for a sprinkle.

Edit: Rather grey and damp in Kenilworth around 10:30am.

P.S. Much warmer from Friday onwards.
 
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Gordon_R said:
Another weak cold-front passing just south of CT today. The forecasts are hard to determine in this kind of situation: yr.no shows 0.1mm, so don't expect too much, but prepare for a sprinkle.

P.S. Much warmer from Friday onwards.
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Yeah we must enjoy this cool breeze.
Im leaving 5am tomorrow for Porterville, hiking and sleeping in the mountains until Sunday
Weather looks to be mid to upper 30s :oops:
I hope the rivers are flowing, Im gonna die
 
Pineapple Smurf said:
Yeah we must enjoy this cool breeze.
Im leaving 5am tomorrow for Porterville, hiking and sleeping in the mountains until Sunday
Weather looks to be mid to upper 30s :oops:
I hope the rivers are flowing, Im gonna die
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Wave to tartlet as she passes you on her way home....
 
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