God this is frustrating.
Back in January we had bitterly cold air next door but insufficient synoptics
Now we have insufficiently cold air next door but perfect synoptics.
Goddam this, can we not get a single ice day or more than widespread snow event per cold spell; you'd think the EU is regulating against them or something (it wouldn't surprise me).
/rant
Seriously though, this is not anywhere near as good as it looks. A good lake effect snow event (snow showers) requires the following:
0) Deep cold air in place (zeroth because this is just obvious)
1) High thermal gradient
2) Low directional sheer
3) Low speed sheer
4) Long fetch (and obviously it needs to be blowing from the sea in the first place)
5) Cold air advected (note this is independent from 0, you can get WAA while it is cold)
6) Moderate wind speeds (not too high or low - level is irrelevant due to the restriction imposed by 3)
7) Relatively low pressure
So lets examine this. I'm going to rate on the following scale:
Excellent - conditions very favorable
Good - conditions favorable
Marginal - conditions just favorable
Poor - conditions unfavourable
Terrible - conditions very unfavourable
0)Excellent outside the boundry layer itself we are not even marginal - its easily cold enough.
1)Marginal/Good 850hpa-surface is broadly 13C-16C. This is acceptable, 13C is getting to the point where it is marginal, 16C is quite good. Overall acceptabl
2)Terrible-Good Highly variable. Frontal activity moving in after midweek causing cross winds.
3)Terrible-Good As above, highly variable.
4) Good/Excellent most of the time the wind is blowing from the north or north east with an effectively infinite fetch. Marginal at times in the south east as the wind turns SErly
5) Marginal/Good most of the time there is weak CAA with some strong CAA at first, some weak WAA possible midweek. Generally good though and occasionally excellent.
6) Terrible-Excellent ridiculously variable; sometimes the air will be virtually static (and therefore terrible) and at othertimes especially later it may even be slightly too high.
7) Marginal/Good/Excellent most of the time it will be good or excellent but occasionally in the west the pressure will rise above 1020mb which is getting marginal.
So my overall assesment is very mixed. Please keep in mind that cold air and a roughly NE wind is NOT the only criterion for lake effect snow. Honestly I think it could be alot better than it is; in the south especially it will be so marginal I think we can rule out impressive streamers. Hope for frontal snow (Harry rather than Sally), its far more low maintance and really only cares about how cold it is (and its easily cold enough).
2023/2024 Snow days (approx 850hpa temp):
29/11 (-6), 30/11 (-6), 02/12 (-5), 03/12 (-5), 04/12 (-3), 16/01 (-3), 18/01 (-8), 08/02 (-5)
Total: 8 days with snow/sleet falling.
2022/2023 Snow days (approx 850hpa temp):
18/12 (-1), 06/03 (-6), 08/03 (-8), 09/03 (-6), 10/03 (-8), 11/03 (-5), 14/03 (-6)
Total: 7 days with snow/sleet falling.
2021/2022 Snow days (approx 850hpa temp):
26/11 (-5), 27/11 (-7), 28/11 (-6), 02/12 (-6), 06/01 (-5), 07/01 (-6), 06/02 (-5), 19/02 (-5), 24/02 (-7), 30/03 (-7), 31/03 (-8), 01/04 (-8)
Total: 12 days with snow/sleet falling.