Having looked at the WRF the synoptics are the best they have been in years for an ice event, wind direction changes as a function of height are not unusual, but later this week we may hit the sweat spot; a frigid south easterly at the surface and a warm south westerly above it. This is a recipe for some potentially very rare and severe weather which includes the possibility of ice (american sleet) and freezing rain. Even earlier on in the week we have some good potential with milder air lurking in the west moving over freezing air in the east.
Post any observations of icing or otherwise unusual precipitation here. Of course with such cold surface temperatures it wouldn't take much to turn ice to snow if the warm air makes it slightly less far than predicted. Please note, the 850hpa -6C benchmark is now entirely useless; use other proxies and preferably skew ts to ascertain precipitation type.
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.