simonjk
Well-Known Member
Hello and Happy New Year!
I'm in a pondering mood, hope you don't mind? Having been looking at the charts over the past few days, highlighting the risk of a severe outbreaks of severe easterly cold, today's run of the GFS and other models is changing things a bit. Now looking like a shorter lived cold snap this weekend, and a return to milder west or southwesterlies next week.
That's not all bad news for me as this backs up my 30 day forecast (http://www.weatherweb.net/30day.htm), however it poses the question about whether the model is picking up the cold air properly...I suspect that it is.
Sea surface temperature anomalies are great for taking a first step when drawing comparisons between years. For example, take a look at this chart and then compare this with January 1996 at this chart They do look similar don't they?
What can we infer from this? Well, drawing my attentioin is the area of warmer water off northwest Africa, I believe this would tend to encourage convection and hence lower pressuing here, tending towards low pressure. Now, mid Atlantic now has temperatures around normal, so I can't pick up much here. The Mediterranean is cooler so strictly speaking this should raise pressure here, although any lows forming off Africa would probably drift northeast.
The Pacific, west of north America has a large "stripe" of below normal temperatures, so could this encourage higher pressure? If so, I think there would be a ridge through the Pacific, dipping to a trough over North America, with a resultant rise in pressure in the Atlantic, extending through the Mediterranean. Add to this lower pressure off northwest Africa and this may well promote the easterly winds through much of northern Europe (including the UK).
After all that, what am I trying to say? Well, I suspect that as in January 1996 there will be a tendency for colder weather to penetrate the UK at some stage. It will go colder this weekend, perhaps with snow flurries in the east, but I'm not convinced that this will last for longer than say, 4 or 5days. However, I do think that after a week or so of milkder weather, we could see a return to colder weather at the end of the month, lasting into the beginning of February. This period dominated by high pressure over Scotland and low pressure somewhere close to Iberia with the UK stuck in the easterly winds in-between.
So there we go, I can take my anorak off now, hope you find my ramblings interesting?
Best wishes,
Simon
Simon Keeling
I'm in a pondering mood, hope you don't mind? Having been looking at the charts over the past few days, highlighting the risk of a severe outbreaks of severe easterly cold, today's run of the GFS and other models is changing things a bit. Now looking like a shorter lived cold snap this weekend, and a return to milder west or southwesterlies next week.
That's not all bad news for me as this backs up my 30 day forecast (http://www.weatherweb.net/30day.htm), however it poses the question about whether the model is picking up the cold air properly...I suspect that it is.
Sea surface temperature anomalies are great for taking a first step when drawing comparisons between years. For example, take a look at this chart and then compare this with January 1996 at this chart They do look similar don't they?
What can we infer from this? Well, drawing my attentioin is the area of warmer water off northwest Africa, I believe this would tend to encourage convection and hence lower pressuing here, tending towards low pressure. Now, mid Atlantic now has temperatures around normal, so I can't pick up much here. The Mediterranean is cooler so strictly speaking this should raise pressure here, although any lows forming off Africa would probably drift northeast.
The Pacific, west of north America has a large "stripe" of below normal temperatures, so could this encourage higher pressure? If so, I think there would be a ridge through the Pacific, dipping to a trough over North America, with a resultant rise in pressure in the Atlantic, extending through the Mediterranean. Add to this lower pressure off northwest Africa and this may well promote the easterly winds through much of northern Europe (including the UK).
After all that, what am I trying to say? Well, I suspect that as in January 1996 there will be a tendency for colder weather to penetrate the UK at some stage. It will go colder this weekend, perhaps with snow flurries in the east, but I'm not convinced that this will last for longer than say, 4 or 5days. However, I do think that after a week or so of milkder weather, we could see a return to colder weather at the end of the month, lasting into the beginning of February. This period dominated by high pressure over Scotland and low pressure somewhere close to Iberia with the UK stuck in the easterly winds in-between.
So there we go, I can take my anorak off now, hope you find my ramblings interesting?
Best wishes,
Simon
Simon Keeling
