Joe Bloggs

Good to see snow reports in here already :-) 00z Arpege is good for Tuesday and Wednesday across most of the NW (including western parts), GFS isn’t bad either. TBH it’s going to be a week of checking the weather radar and not bothering too much about the short range models, they have too many pit-falls.

Yes Tuesday morning now looks better for us, we’re back in the game for the North Sea little low. Still could change again though. Euro4 ok for the Manchester area.

Bit of a change in the 12z runs, precipitation reaches us earlier on Tuesday and reaches as far west as the Wirral and North Wales (GFS). I’ve seen enough to see that it may happen no matter what future charts show - will be a radar job from tomorrow onwards.

It may miss us completely but I still think we have a strong chance of picking up convective features Tuesday night - Thursday. Models will all be useless at picking up these showers at this range.

I keep saying December 1996 for a good Manchester easterly snow event but I may be getting confused with Jan 1996..

06z GFS shows us staying generally dry until Wednesday afternoon http://www.wetterzentrale.de/maps/GFSOPUK06_81_43.png

We’re definitely in the warning area Tuesday and Wednesday

We’re now covered by a yellow warning. Not surprised by this.

Usual caveats apply, but the 06z output is ramping up the snow possibilities for Tuesday now. At the moment we’re in a good location for a system moving in off the North Sea and pushing SW. could change.

Latest fax charts show a feature passing across us btw http://old.wetterzentrale.de/pics/brack2.gif http://old.wetterzentrale.de/pics/brack2a.gif

Yep. To be honest I agree with you that east of the region is definitely favoured. We shall see. Exceptionally cold whatever the outcome.

I don’t agree with much of this post, simply because it doesn’t correspond with my (admittedly limited) experience of these events in the past. Think Feb 1991 and December 1996. On these occasions snow showers pushed as far west as North Wales. We will have to see. I have been lucky enough to see the internal Met Office guidance for next week and they make a specific point of saying that because of the significant nature of the cold pool, the sun’s effect will be largely minimal. Thought this was an interesting point and it is very easy to assume that given the time of year, solar influence will be significant - apparently not the case.

Yes no chance of rain that’s for sure. Just powder snow. Good to see that we have precipitation forecast though. I’ve just checked all the other models and none of them look particularly dry.

I will join you in giving Euro4 a miss

I’ll just leave the latest Arpege here... ;-)

To be honest mate I think you’re barking up the wrong tree. The snow shadow only really comes into play when frontal precipitation is involved (think a slider event, or a low pushing up from the south), combined with winds from the SE, East or NE. Convective showers or troughs are completely different affairs and showers shouldn’t have much difficulty getting across the Pennines if the flow is dynamic and cold enough (certainly looks that way), no matter if the wind is from the SE, East or NE. In fact I’ve noticed in the past that showers can actually reinvigorate as they reach the Pennines with East Manchester getting a good covering. I think it’s looking like a hit and miss affair for next week, but convective easterlies are NOT necessarily a dead duck for the NW, especially with a cold pool as deep and as unstable as this. I think most of the region will get at least a few flurries with the sweet spots (Pennine areas) maybe getting 10cm plus, but that’s maybe being conservative. To be frank I wouldn’t bank on a low pushing in from the south, then we would have to start worrying about the rain shadow effect and we could well miss out, unless the winds are very slack.

I’m sorry, but this is incredible. Data from ECM.

The snow shadow effect also comes into play on an easterly, but usually for frontal snow events, rather than convective.

Yes definitely take with a pinch of salt for now. Feb 2005 saw plenty of snow showers pushing over the Pennines, same in Feb 2009. Feb 1991 and Dec 1996 were snowy for Manchester I think. We're looking for a streamer to develop towards the Humber. The whole of Northern England could potentially do well if we're lucky, with snow showers potentially even pushing into North Wales. Too early to say. Depends on the exact nature of the flow. Unlike SW England we have the benefit of a longer sea track and a shorter land track. Not that far to Hull. Also the snow shadow effect usually only comes into play when the precipitation is frontal, rather than convective. We shall see, but I'm cautiously optimistic, if the flow continues to look like the below. I'm convinced we'd see showers.

The Manchester snow shadow (from memory) doesn’t really come into play when we’re talking about convective snow showers from the east - indeed the Pennines can sometimes pep them up. Saw that in 2005.

I’ve just made this point on TWO. Yes I count 4 of the GEFS which show high pressure for much of Northern Britain midday Tuesday with relatively disappointing cold air advection away from the far south east. P17 is the worst. In my view if there is a sudden last minute backtrack then it will be something akin to this scenario, but low risk in my view, given all the other output and the vast majority of the GEFS.

Meteo Group app. I don’t think I’ve ever seen such significant cold forecast for Manchester - this one is normally conservative

I have seen deep snow in Manchester on a convective easterly (showers and troughs). If I remember correctly (was only a young kid), December 1996 and Feb 1991. Kevin will correct me if I’m wrong.

Snowing lightly here. We’re catching the western edges of these showers (just)

Light snow in Manc city centre now. The front from the west is now merging with the showers from the East.