North West Regional Discussion 30 December 2020 onwards

[Geordiesnow]

1 minute ago, Kasim Awan said:

My friend in Leyland has frozen wet snow. The "warm layer", which I will now refer to as the >0c layer, melted the snow to a wet snow. This then froze as it reached 100 metres asl. What an interesting weather phenomenon.

But once snow melted in the air on the way down, it can't turn back to snowflakes? Would that suggest the warm sector is perhaps not that strong? 

[Backtrack]

5 minutes ago, Kasim Awan said:

My friend in Leyland has frozen wet snow. The "warm layer", which I will now refer to as the >0c layer, melted the snow to a wet snow. The water content then froze as it reached 100 metres asl. This creates an "icy snow". What an interesting weather phenomenon.

Just ice pellets then really, same kinda ‘creation’

[Kasim Awan]

4 minutes ago, Geordiesnow said:

But once snow melted in the air on the way down, it can't turn back to snowflakes? Would that suggest the warm sector is perhaps not that strong? 

The snow only melted partially, to wet snow before refreezing near the surface as the warm layer there was too shallow to fully melt it.

[Backtrack]

There is no modelled ‘warm sector’ as far as I can see. Just the same thing that happens every single year regarding coastal marginality as the sea will modify the air as winds pick up closer to the coast. Anywhere east of Warrington tends to be immune, especially during a slacker flow

[Backtrack]

EURO4 forecasting showers starting to appear in the next hour, falling as snow even to the coast. So keeping an eye on that, as it's looking fairly accurate comparing it to the radar so far

[Mark.C]

3 minutes ago, Backtrack said:

EURO4 forecasting showers starting to appear in the next hour, falling as snow even to the coast. So keeping an eye on that, as it's looking fairly accurate comparing it to the radar so far

jaffa cakesed with rain here not long back 

[Kasim Awan]

10 minutes ago, Backtrack said:

There is no modelled ‘warm sector’ as far as I can see. Just the same thing that happens every single year regarding coastal marginality as the sea will modify the air as winds pick up closer to the coast. Anywhere east of Warrington tends to be immune, especially during a slacker flow

You're bang on the money mate, and the warm layer (not sector which is a general mild area from a triple point low) will take some time to move inland so a good shot for all areas tbh.

Also, any decent intensity precip where there is a shallow warm layer will erode the warm layer inland producing snow. Parts of the coast dew points over freezing forget it.

[Backtrack]

1 minute ago, Kasim Awan said:

You're bang on the money mate, and the warm layer (not sector which is a general mild area from a triple point low) will take some time to move inland so a good shot for all areas tbh.

Also, any decent intensity precip where there is a shallow warm layer will erode the warm layer inland producing snow. Parts of the coast dew points over freezing forget it.

Just looking at the NMM, it's looking good tbh, not much modification forecast, but it never really is, haha. Temps on the Wirral have shot up now as the winds start to arrive. Perhaps I will be able to escape it as the flow is so slack.

[Backtrack]

5 minutes ago, mark blackpool said:

jaffa cakesed with rain here not long back 

What was the air temp when the rain started? Fleetwood is reporting 5C, so it's no wonder

Edited December 31, 2020 by Backtrack

[Kasim Awan]

3 minutes ago, Backtrack said:

What was the air temp when the rain started? Fleetwood is reporting 5C, so it's no wonder

Crosby is at 3C. East of St Helens I think will stay below 0 for the most part.

[raul_sbd]

3 minutes ago, Kasim Awan said:

Crosby is at 3C. East of St Helens I think will stay below 0 for the most part.

Strange here in Sale has shoot up again to 0.2c from -0.2c not long ago 

[More Runs Needed]

So this shower activity is not part of the activity we're expecting after 4am? Was this expected? 

[Mark.C]

8 minutes ago, Backtrack said:

What was the air temp when the rain started? Fleetwood is reporting 5C, so it's no wonder

+2C It was -1 for ages beforehand Everything frozen 

[Kasim Awan]

Just now, raul_sbd said:

Strange here in Sale has shoot up again to 0.2c from -0.2c not long ago 

Atmospheric chaos. Wouldn't worry about those minor fluctuations. Related to eddies & chaotic parcel movement.

Tonight is very interesting from a verification perspective. Really good potential inland. Let's see what happens.

[Backtrack]

3 minutes ago, Dkeane3 said:

So this shower activity is not part of the activity we're expecting after 4am? Was this expected? 

Euro4 picked up on it and has nailed it so far

[Backtrack]

3 minutes ago, mark blackpool said:

+2C It was -1 for ages beforehand Everything frozen 

Crazy, the punishment for living at the coast I guess. You get the beach but miss the snow, lol.

[Kasim Awan]

As fog fluctuates, there are eddies of sinking & rising air on the side of the fog. This produces temperature changes under half a Degree usually.

[Backtrack]

Just now, Kasim Awan said:

As fog fluctuates, there are eddies of sinking & rising air on the side of the fog. This produces temperature changes under half a Degree usually.

From past experience here, fog can change the temperature up to about 3-4C! 

[Mark.C]

3 minutes ago, Backtrack said:

Crazy, the punishment for living at the coast I guess. You get the beach but miss the snow, lol.

The worst of both worlds

[Kasim Awan]

1 minute ago, Backtrack said:

From past experience here, fog can change the temperature up to about 3-4C! 

Yes. This is not probably related to the eddies though.

[Winter Hill]

Just had hefty snow shower..

[More Runs Needed]

So surprised.... A light snow shower has just started

[More Runs Needed]

Anyone want to give me the best time to wake up for falling snow?

[raul_sbd]

Snow shower in Sale now

 

[raul_sbd]

Not looking bad the radar for later on.. *maybe* we are lucky..