Wales Cymru Cold Spell Discussion

[Jamie.]

I'm not too far from the sea and the dew point here is currently -4C (S Wales).

I hope it can stay below freezing when the front arrives...

Edited December 18, 2009 by Jamie.ed

[swales]

I'm not too far from the sea and the dew point here is currently -4C (S Wales).

I hope it can stay below freezing when the front arrives...

Where exactly are you? Bridgend?

[Snowmadsam]

Has the snow gone back down south on the radar or is it just me?

[swales]

Has the snow gone back down south on the radar or is it just me?

What?

[J10]

Has the snow gone back down south on the radar or is it just me?

The precipitation for this evening is set to be blown SW on the NE winds, so until the morning, this situation is not likely to improve.

Better off seeing the temps plummet in readiness for tomorrows front, the colder tonight the better.

[Snowmadsam]

if it IS me but I'm not sure please help

Shaun what do you mean by what?

[swales]

if it IS me but I'm not sure please help

Shaun what do you mean by what?

Sorry didn't understand what you mean...

Precip is likely to clear for tis evening... maybe one or two showers but pffft crap

[Snowmadsam]

o ok thanks for telling me :-D

[keithlucky]

The precipitation for this evening is set to be blown SW on the NE winds, so until the morning, this situation is not likely to improve.

Better off seeing the temps plummet in readiness for tomorrows front, the colder tonight the better.

If this rain is intense and rapid passing through as the met say,wont the dew point drop?

[Jamie.]

Where exactly are you? Bridgend?

Monmouth .

[J10]

If this rain is intense and rapid passing through as the met say,wont the dew point drop?

In winter, much of what falls from the sky initially is snow, but this then thaws in normal conditions to fall as rain. When the precipitation is heavy, the requires more energy to melt the snow, and as a result temperatures drop, this process is known as evaporational cooling.

At marginal rain snow conditions this can lead to the rain at ground level, bring replaced by sleet and then snow, as there is not enough energy left to thaw the snow as it falls. However this only happens at the margins of rain and snow and in heavy precipitation, so if the ground temp is 5c, no amount of rain will convert it to snow.

As dewpoints are a product of humidity levels, the heaviest of the ground rain could cause the dew point to drop, but not to any great extent.

What will cause the dew point to drop, are the much colder temps to the north and this may undercut the front to the south, causing any rain or sleet to readily turn back to snow close to the back edge of the front.

[TonyH]

I thought it would be a cold one with the clear calm continental air tonight.

-6c already here.

[Cymro]

it's -8 here blimy i didnt expect it to be this low tonight tbh when it hit -6 at 8 o clock i was suprised but this takes it to another level, Quite pleased with that considering theres no snow cover on the ground etc.

[Marcus_surfer]

-2C here, rare for the coast, can't believe it will rain saturday night

[Jamie.]

-3C here .

Dew point -5.6C.

[J10]

GFS 18Hz looks better for tomorrow night. look at the chart of Dewpoint and precipiation at midnight, dewpoint below zero across Wales and Precipitation all over Wales.

With plenty of showers to follow on all day,again with dewpoints below zero.

Fax Chart shows occlusion pushing thro8ugh tomorrow with frontal system late evening, with warm sector pushing through Swansea on its eastern edge, so perhaps East Wales will see snow all the way.

[SnowStorm(Jamie)]

Yup the 18Z does look better for snow in Wales, still starting as rain and sleet in the west before turning to snow.

[Cymro]

GFS 18Hz looks better for tomorrow night. look at the chart of Dewpoint and precipiation at midnight, dewpoint below zero across Wales and Precipitation all over Wales.

With plenty of showers to follow on all day,again with dewpoints below zero.

Fax Chart shows occlusion pushing thro8ugh tomorrow with frontal system late evening, with warm sector pushing through Swansea on its eastern edge, so perhaps East Wales will see snow all the way.

Ti'n dweud bod e'n pasio abertawe ar yr ochr dwyreiniol ydy hynny'n golygu bydda i yn Nyffryn Aman yn gweld eira'r holl ffordd?

You know you say that the eastern side will be pasing Swansea does that mean that I will see snow all the way here in Amman Valley?

[swales]

-2C here, rare for the coast, can't believe it will rain saturday night

Only -2? It's minus 6 here and I'm like 6 miles to Pembrey at minus 3

[J10]

Ti'n dweud bod e'n pasio abertawe ar yr ochr dwyreiniol ydy hynny'n golygu bydda i yn Nyffryn Aman yn gweld eira'r holl ffordd?

You know you say that the eastern side will be pasing Swansea does that mean that I will see snow all the way here in Amman Valley?

According to the FAX areas to the east of Swansea (hopefully inclusive) should see snow all the way, although your altitude should help, however the snow risk does seem to be transferring westwards.

[Cymro]

According to the FAX areas to the east of Swansea (hopefully inclusive) should see snow all the way, although your altitude should help, however the snow risk does seem to be transferring westwards.

Well that's great news belive it or not we had some graupel earlier mayeb left over from a shower. Its -8 out there so the ground will be lovely and cool for lying snow. hasnt got above -1 all day. got down to -6 last night. Who knows what sunday night will bring with hopefully a covering on the ground?.

I do hope however that this becomes a more widespread event in Wales and i personally don't forsee it starting off as rain anywhere away from extreme coastal districs due to the intesity of the cold that's over Wales at the moment.

[J10]

Well that's great news belive it or not we had some graupel earlier mayeb left over from a shower. Its -8 out there so the ground will be lovely and cool for lying snow. hasnt got above -1 all day. got down to -6 last night. Who knows what sunday night will bring with hopefully a covering on the ground?.

I do hope however that this becomes a more widespread event in Wales and i personally don't forsee it starting off as rain anywhere away from extreme coastal districs due to the intesity of the cold that's over Wales at the moment.

The 18Hz run has the colder air digging in much quicker turning any rain to snow much quicker.

I hope your are right, the colder it gets the better and in many inland parts tomorrow it will struggle to get much above freezing. The 18Hz also shows tons of potential for heavy snow showers set to fall by morning.

Any altitude is set to be a big help for this event

[SnowStorm(Jamie)]

According to the FAX areas to the east of Swansea (hopefully inclusive) should see snow all the way, although your altitude should help, however the snow risk does seem to be transferring westwards.

Yup we do seem to be on the borderline here in Swansea. With a bit of luck much of Wales should see some falling snow.

[Barb]

Looks decent for tomorrow, bit dissapointed with the lack of snow showing next week though. All to change though no doubt. Hopefully.

[Jamie.]

With it being so cold at the moment it's wierd to think in 24hours it could be raining!

Just looked at BBC weather and they predict a mixture of rain, sleet and snow for Wales Tomorrow Night with the snow mostly for North. Once it clears south, temps are -2C. 8-|