November is often a month that sees plenty of Atlantic driven weather, the average temperature in November is actually higher than that of March, so will we see a typical November? Or, like last year will we see winter biting in early?
In the last couple of days I’ve been keeping an eye on the models and, I’ll admit this forecast is a rather difficult one with some conflicting signals, some calling for a milder, wetter November all the way through, and some promoting a pattern change sometime through the second or third week of the month. Lets first take a look at a couple of weather models.
The chart above shows us the predicted NAO and AO indexes, they’re both hinting, although not solidly, at moving into a weak negative as we move into November, this tells me that we could start to see hints of High Pressure developing across the Arctic and into the Atlantic.
The chart above is the 8-10 day 500mb charts, these charts show us the most likely pressure pattern over the course of the next 8-10 days, and this of course takes us into the first part of November. What they’re showing is generally a good signal for Low Pressure in the Atlantic and over the United Kingdom, suggesting it’ll be an unsettled, wet and windy start to the month. We also have weak signals of High Pressure over the Arctic, too, which does tie in with what the NAO/AO are currently forecasting.
The above chart shows us the 30hPa Stratospheric temperature profiles above the Arctic, currently these temperatures are below average which, usually tend to mean a stronger Polar Vortex which keeps much colder air bottled up over the Arctic, at this moment in time, there is no forecast for warming in this region.
The above chart shows us Sea Surface Temperature Anomalies across the globe, if we look towards the UK there are no big anomalies really showing up, other than the cold and warm anomalies towards the North, up towards the Arctic, with the warm and cold anomalies very close together, a stronger Volar Portex seems likely thanks to that pressure gradient.
November Weather Outlook:
Based on the factors above, the first half of November is looking generally unsettled with Low Pressure close to, or over the United Kingdom, a mean trough seems likely to be placed just to the West of the United Kingdom, so those further North and West are likely to see the wettest weather. As we move into the second half of the month confident dramatically drops, due to the conflicting signals it’s hard to get a clear picture of what’s likely to happen, however based on the current weak signals for High Pressure to build across the Arctic it would seem probable that we;ll see a pattern change mid-month, with High Pressure across the Arctic we’re likely to see the Jet Stream shunted Southwards, helping to draw in some colder air from the near continent.
So, a mild, wet and windy first half to the month, beyond that, it’s likely to turn cooler with snowfall possibly becoming increasingly frequent