Breakdown Of Cold Weather Not Yet Guaranteed

ECM weather model (c) Meteociel
iWeather Online Forecaster Peter O'Donnell writes: The medium to long range weather models indicating a breakdown in the current setup to much milder conditions are not very convincing. Some of the lesser models have no breakdown at all (the Russian and Australian models, yes there are such, have continued cold). Most peculiar of all to my eye is the GEM, it shows mild air pushing easily north with almost no height rises at 500 mbs and the jet stream still pushing into France.

The Cold V Milder airmass battle hinges on a slow-moving and rather non-energetic low south of Nova Scotia that on some model runs is hanging back for a very long time in that general area, while cold air pushes south of Iceland into the central Atlantic. This is a real recipe for model disaster, all that needs to go wrong for the likes of the ECM and GFS is that the low sends out a weak frontal wave and the cold builds in stronger. Then it would be a flip-flop on the next set of runs reverting back to the cold hanging on and even building back stronger than ever.

What I'm saying is, don't count on this warmup being either strong or sustained. Some milder air could come oozing in on the 26th and then just lose its way without much support.

As everyone is saying from top to bottom of the feeding chain of the weather game, this is a true forecasting nightmare and the signals are mixed to say the least. Past climatology says watch out for the breakdown delay and snow or mixed precipitation as a possible result. Also, this just doesn't seem like a realistic sequence, coldest 30-day period on record for this recent period at least, going rapidly to a zonal flow? Just doesn't seem realistic, a battleground period seems more realistic.
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Irish Weather Online's Daily Long Range Weather Forecast is provided by Peter O'Donnell. Peter is a Canada-based climatologist who specialises in providing long range weather forecasts for Ireland and the United Kingdom.