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Tracking the potential Polar Low - Thursday into Friday


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Agree that there is potential for 3-5 cm snowfalls along eastern flank of this rapid moving low.

 

Southwest Wales should be placed under a red alert for very strong winds overnight, pressure gradient on western flank of low looks extreme on meso-scale models. WNW to NNW 70 mph gusting to 110 is quite possible with this once it gets over the Irish Sea and moves inland in central Wales. For parts of Cornwall, Devon and western Somerset, 60 mph gusting to 100 by about 0300-0600h. These may be the greatest impacts of the system.

WOW!

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Is it only me, or are the 'is it a/isn't it a Polar low' reamrks just plain old semantics.........as long as I get a dumping of snow, you can call it a lesser spotted chocolate teapot if you want    

Hi all.  Had great fun following this brilliant forum last night.  Just to introduce myself; I was senior forecaster at Manchester Weather Centre for 20 years, now retired.  I think that it was defini

so then....members in the west believe it'll track down the irish sea giving the action in the western regions...... members in the east believe it'll track though northern england and the SE giving s

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Agree that there is potential for 3-5 cm snowfalls along eastern flank of this rapid moving low.

 

Southwest Wales should be placed under a red alert for very strong winds overnight, pressure gradient on western flank of low looks extreme on meso-scale models. WNW to NNW 70 mph gusting to 110 is quite possible with this once it gets over the Irish Sea and moves inland in central Wales. For parts of Cornwall, Devon and western Somerset, 60 mph gusting to 100 by about 0300-0600h. These may be the greatest impacts of the system.

 

Really? Doesn't seem that bad to me. 

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Get set...a snow earthquake is quite possible if this Polar Low hits the British mainland.

Ah, I see the Daily Express hired you then Barry!  :wink:

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The NMM4 shows precip moving southeast with the polar low as expected breaking up over land. I don't think any computer model as got this one just right  ,with one or two places getting plastered with snow. Just shows you ,once you've got the cold in, let the fireworks start... :cold:

post-6830-0-83893800-1422562823.jpg

post-6830-0-84325400-1422562897_thumb.gi

post-6830-0-06655700-1422562976_thumb.pn

post-6830-0-85814900-1422563021_thumb.pn

post-6830-0-08822600-1422563145_thumb.pn

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IMO I think many of posters here have an inaccurate track of this feature. I'm fairly certain it will track on current trajectory down through the spine of Wales, Bristol and the IOW. Snowfall East of that but how far uncertain and yes severe gales for a short time to the SW of it. Not quite sure which side of the coin I lie on. Time will tell.

Looks a little further East to me gibby but I could be wrong, one thing for sure some people are going to end up disappointed, many maybe.

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Rain reports over NI so its official this is the first ever rainy polar low to hit the UK!

 

OK, we get it, you don't think it's a Polar Low besides the professionals calling it one.

 

P.S - Polar Lows can deliver rain, or snow. It's currently snowing on it's Eastern Flank in Scotland.

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On the western flank, but it seems to be remaining as snow on eastern flank according to net-wx radar!

 

This is based on model data, I'm guessing it will be solely 850 dry bulb temps. This is only one of many parameters that determine precipitation type.

Edited by Nick L
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Rain reports over NI so its official this is the first ever rainy polar low to hit the UK!

 

Bit of sour grapes for IMBY I think...no chance of anything else but rain on the western side of the lows in these set ups, short spell of heavy snow likely on the eastern side even further south.

Edited by KTtom
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To the person who wanted the forming of the polar low saved

[edit] I'll upload the AVI (180MB), in a few minutes it will be at this link:

http://swmo.org/temp/polarlow.avi

 

Mini GIF preview:

 

polarlow_small.gif

 

It's currently snowing/sleeting in the New Forest btw - half a cm on the car.

Edited by simkin
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Bit of sour grapes for IMBY I think...no chance of anything else but rain on the western side of the lows in these set ups, short spell of heavy snow likely on the eastern side even further south.

No chance? Your obviously a more experienced forecaster than the met office who forecast a snow event for the East of NI. But heh ho, that's the weather for you.

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ok, for comparison.......here's the current radar & NMM hi-res modelling (images courtesy NetWeather Extra)

 

radar grab 1 at 2000hrs showing ppn intensity & sferic detections

radar grab 2 at 2000hrs showing ppn type and weather station record dewpoints

NMM grab1 at 2000hrs showing ppn intensity

NMM grab 2 at 2000hrs showing ppn type

NMM grab 3 at 2000hrs showing modeled dewpoints

 

IMO, the NMM is overplaying the rain/sleet element of the 'chocolate teapot' low with lower dewpoints currently being measured over NI than modeled

 

post-4149-0-90797300-1422564129_thumb.pn     post-4149-0-75049100-1422564152_thumb.pn

 

post-4149-0-59876200-1422564199_thumb.pn   post-4149-0-36710300-1422564223_thumb.pn  post-4149-0-01490900-1422564244_thumb.pn

 

 

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The NMM4 shows precip moving southeast with the polar low as expected breaking up over land. I don't think any computer model as got this one just right  ,with one or two places getting plastered with snow. Just shows you ,once you've got the cold in, let the fireworks start... :cold:

 

I hope this is right! I'm in the light brown bit on that chart!

Edited by Jonathan Lang
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The NMM4 shows precip moving southeast with the polar low as expected breaking up over land. I don't think any computer model as got this one just right  ,with one or two places getting plastered with snow. Just shows you ,once you've got the cold in, let the fireworks start... :cold:

To be honest that already looks wrong though , it has the initial streamer far to far East , if you have a look at the current radar it's got that feature just much further west .

Also regarding ones who are fretting about it raining in Ireland remember Ireland's the most western part of our land , there will always be a warm sector on the Western side in these scenarios unless it's wrapped up in true polar air which I thought polar lows are lol shows what I no!

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