SSW warming.
- I do not usually care much about these, but something has piqued my interest.
- Firstly I'm not interested in how hot it is at the north pole, 10hpa temps are for show, but the vortex is what really matters. What does the stratospheric vortex look like?
- It is first displaced well to the south:
with the centre of the vortex over Scandi.
- Then it is almost completely destroyed with winds easterly from the pole to the temperate latitudes. The vortex looks more like a trough at this point.
- Now, why do we care? The reason this might be important is that these winds can downwell into the troposphere. Sometimes in an SSW you still have westerly winds over the atlantic region, and we are all too fully aware of mild -Ve AO dominated patterns. This, though, this is promising. Even during the displacement phase the westerly winds over the atlantic are weak, and look more northerly over the UK. If this downwells it would create a cold pattern.
So yes, for the first time in several years I have made a SSW post because I actually think there might be something substantive to it now.
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.