Shortwaves are starting to be picked up in the mid-Atlantic and these are causing the usual volatility in the model output.
Overall, a less clear picture going into next week than was the case before.
This is why I've been very broad-brush with the situation next weekend, as the pendulum keeps shifting between snow being the dominant precipitation type and rain being dominant.
The exact positioning and intensity of the LP seems to be critical. Just look at how different the 06z is to the 00z as a result of the LP being centered further south and also deeper - there's a lot more mixing out of the cold air and Saturday's situation ends up being quite frankly disastrous for those trying to retain any lying (mostly shallow) snow. The 00z had DPs of zero or below all day, which is great for snow retention.
Unfortunately the ECM 00z was about as naff as the GFS 06z so best to keep expectations on the floor for now - but there's still a fair chance that the LP aligns more favourably as it does on the UKMO 00z so no need to throw toys out of prams.
I continue to be more interested in the potential early on Thursday across the S and SW. The 00z and 06z GFS runs both give me hour after hour of what appears to be a snow streamer event, but the 00z WRF has the dew points 2 or 3*C higher and just throws down some rain.
I can see two main reasons for this; the first is that the wind direction edges a little more S of west on the WRF run, while the second, probably more significant reason is a vast difference in the modeled dew points over the ocean.
Worryingly, I can see that GFS is a couple of degrees too high with the dew points in some parts of the Atlantic this morning, based on buoy observations.
If the model is failing to account for the influence of the Atlantic ocean on the dew points, it's consistent prediction of snow on Wednesday night may be totally far-fetched. That would be a real downer for me, as I can't see much to get interested in for the weekend at this point in time... but very typical of this winter so far.
I am already bracing myself for another letdown, to be on the safe side, and that's what I feel is advisable to others across SW and CS England.
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T-Max: 30.2°C 9th Sep (...!) | T-Min: -7.1°C 22nd & 23rd Jan | Wettest Day: 25.9mm 2nd Nov | Ice Days: 1 (2nd Dec -1.3°C in freezing fog)
Keep Calm and Forecast On