North West Regional Discussion 30 December 2020 onwards

[Kasim Awan]

Just now, Winter Hill said:

I’ve had some very good snowfall from an Easterly, but like you say, the showers rapidly die a death as they get to my location. Once the showers get to the Bolton area they almost fizzle out when heading to the Wigan area to my west. 

That's why you want an ENE - the upcoming flow is ENE however heights much higher, temps higher & winds lighter. So I'm guaging for 1-3cm above 225m in the east & scattered dustings locally 1cm further west as a middle ground outlook 4th-6th. Kinder Scout 10cm. 

[Joe Bloggs]

Still prefer a convective easterly (with troughs etc) to an easterly based frontal event living here.

When the wind is from the east, show me an example of a front delivering anything under than a dusting in Manchester, I bet you’ll struggle to find one. 
 

Have learnt the hard way living here that the “holy grail” of a low pushing into an easterly flow just doesn’t work out - holes appear on the radar as if by magic. 
 

2013 and the slider lows were a nightmare for it. 

Edited January 1, 2021 by Joe Bloggs

[Kasim Awan]

5 minutes ago, Joe Bloggs said:

Still prefer a convective easterly (with troughs etc) to an easterly based frontal event living here.

When the wind is from the east, show me an example of a front delivering anything under than a dusting in Manchester, I bet you’ll struggle to find one. 
 

Have learnt the hard way living here that the “holy grail” of a low pushing into an easterly flow just doesn’t work out - holes appear on the radar as if by magic. 
 

2013 and the slider lows were a nightmare for it. 

Yes, the front with easterly winds produce a strong orographic drying effect / forcing, with precipitation / convection reforming west of the M60. A classic is 22nd March 2013.

The showers, on the other hand, are not subject to this "forcing" & so undergo decay over the east of the region this often bringing snow to Manchester. Additionally, showers in an easterly whilst are weakened by the Pennines, there is also a minor element of funnelling & precip promoting uplift which can locally increase accumulations. This often found in Glossop / Hyde area before it decays into Levenshume.

[itsnowjoke]

Need some more snow my snowman looks like he’s on a diet need to plump him back up 

[damianslaw]

BBC have me down for a min of -5 degrees tonight, Met Office just -2 degrees. Usually BBC understimates the cold, and Met Office is closer to the mark. Could be our coldest night of the season ahead..

Signs of a cold night in the offing are usually marked by a rapid drop in temps around now, 0 degrees or below before 5pm, this happened on Wednesday everything sparkling white quickly, yet cloud encroached through the night and whilst giving us a bit of snow, prevented very low minima. Tonight though we do have forecast very clear skies so despite starting on a higher note, they should drop and drop by the hour.

Tomorrow promises to be another excellent mid winters day with blue skies, sunshine, light winds and I suspect frost lingering in most places all day.

[Weather-history]

Dipped down to 0C, now. Been a bit of a thaw today but should record another day of snow cover under Met Office rules tomorrow

[Kasim Awan]

That low about to disrupt south into UK is a sizeable shortwave so has reasonable levels of convergence - potential significant snow then easterly.

PLUS.. much less size to the low than earlier dartboard solutions. This more optimal for a later easterly.

Edited January 1, 2021 by Kasim Awan

[Frost HoIIow]

2 hours ago, Winter Hill said:

I’ve had some very good snowfall from an Easterly, but like you say, the showers rapidly die a death as they get to my location. Once the showers get to the Bolton area they almost fizzle out when heading to the Wigan area to my west. 

Yes Greater Manchester has it's own microclimate more than most cities - generally the further east you go in the city the better you fare from an Easterly in regards to the streamer showers not fizzling out. Same with polar maritime masses, but not because of the precipitation weakening...but because there's less modification further inland from the sea so again it's best to be further east. Dew points are often lower further inland too.

[Joe Bloggs]

 

2 hours ago, Kasim Awan said:

Yes, the front with easterly winds produce a strong orographic drying effect / forcing, with precipitation / convection reforming west of the M60. A classic is 22nd March 2013.

The showers, on the other hand, are not subject to this "forcing" & so undergo decay over the east of the region this often bringing snow to Manchester. Additionally, showers in an easterly whilst are weakened by the Pennines, there is also a minor element of funnelling & precip promoting uplift which can locally increase accumulations. This often found in Glossop / Hyde area before it decays into Levenshume.

The T+240 ECM is a good example of this (if the low was a tad further north). Fills me with dread. 

The holy grail of wintry synoptics, cold air in situ with low pressure pushing in, a SE’ly gale. 
 

Talk of the Northern England blizzard would be ongoing, but nearer the time, Manchester’s heavy snow symbols would dry up on the apps, and on the day, all we’ll get is very light snow. Everywhere else in Northern England, including Merseyside would get clobbered.

Hypothetical but demonstrates my point.  

Edited January 1, 2021 by Joe Bloggs

[Weather-history]

Ecm 12z wants to bring a wintry mass across parts

 

[I remember Atlantic 252]

1 minute ago, Weather-history said:

Ecm 12z wants to bring a wintry mass across parts

 

like tues 29th? was good here

[Kasim Awan]

2 minutes ago, Joe Bloggs said:

 

The T+240 ECM is a good example of this (if the low was a tad further north). Fills me with dread. 

The holy grail of wintry synoptics, cold air in situ with low pressure pushing in, a SE’ly gale. 
 

Talk of the Northern England blizzard would be ongoing, but nearer the time, Manchester’s heavy snow symbols would dry up on the apps, and on the day, all we’ll get is very light snow. Everywhere else in Northern England, including Merseyside would get clobbered.

Hypothetical but demonstrates my point.  

Not neccessarily > lower heights / lightish winds & greater mixing @ 2-7,000ft due to lower forcing and greater convection rates with low heights. Would be decent if slightly further north.

[Weather-history]

1 minute ago, I remember Atlantic 252 said:

like tues 29th? was good here

Don't know but Arpege looks eye opening for West Midlands

Icon 

[captaincroc]

5 minutes ago, Weather-history said:

Ecm 12z wants to bring a wintry mass across parts

 

The Euro4 has something similar but not as defined. Fingers crossed. 

[captaincroc]

1 minute ago, Weather-history said:

Don't know but Arpege looks eye opening for West Midlands

Icon 

Oooh, didn't spot this.  The Arpege has a lot more activity full stop tomorrow than other models

[I remember Atlantic 252]

2 minutes ago, Kasim Awan said:

Not neccessarily > lower heights / lightish winds & greater mixing @ 2-7,000ft due to lower forcing and greater convection rates with low heights. Would be decent if slightly further north.

U must have been buried! that was a very good event here, only time ever sent home from school! childhood days rule

[Kasim Awan]

Hope I'm not loosing ppl here but essentially a linear front with an easterly wind produces more forcing required for the snow shield. Lower heights & a triple point reduce the precip snap back distance meaning convection rebounds further east closer to the Pennines, a la November 1996. @joebloggs 

 

Both events below had easterly winds, one with lower heights & lighter winds.. One was far better for your area..

[Kasim Awan]

3 minutes ago, I remember Atlantic 252 said:

U must have been buried! that was a very good event here, only time ever sent home from school! childhood days rule

I wasn't born till 1998 lol

[Weather-history]

5 minutes ago, I remember Atlantic 252 said:

U must have been buried! that was a very good event here, only time ever sent home from school! childhood days rule

[Joe Bloggs]

7 minutes ago, Kasim Awan said:

Hope I'm not loosing ppl here but essentially a linear front with an easterly wind produces more forcing required for the snow shield. Lower heights & a triple point reduce the precip snap back distance meaning convection rebounds further east closer to the Pennines, a la November 1996. @joebloggs 

 

Both events below had easterly winds, one with lower heights & lighter winds.. One was far better for your area..

Fascinating, thank you  .

The SE’ly snow shield is a really interesting phenomenon, the Peak District are hardly the Himalayas! 

So basically lower heights and lighter winds give us a better chance. 

[WillinGlossop]

Ecm 12z for between now and Monday 72 hours ahead... looks sweet

[Kasim Awan]

7 minutes ago, Joe Bloggs said:

Fascinating, thank you  .

The SE’ly snow shield is a really interesting phenomenon, the Peak District are hardly the Himalayas! 

So basically lower heights and lighter winds give us a better chance. 

It is - the Euro4 is highly rated at the UK Met for modelling the shield.

[More Runs Needed]

A band of snow being forecast for the south of the region by ECM and ICON between 12pm and 4pm tomorrow, looks further west than previous 

Edited January 1, 2021 by Dkeane3

[Backtrack]

35 minutes ago, Weather-history said:

Is that January 11th upcoming, or a chart from the past?

[More Runs Needed]

Just now, Backtrack said:

Is that January 11th upcoming, or a chart from the past?

Upcoming, but seems like a system that would only trend south closer to the time (as usual)