The tabloids have been full of the impending cold spell for days but I’ve held off from briefing up until now, largely because the detail surrounding the change to colder conditions, due to take place through the course of Monday night, has remained rather elusive but also due to the absence of any severe weather warnings upon which to base any message.
That situation has now changed with the issue this morning of a Yellow Alert (medium likelihood of minor impacts) for ice covering just about the whole of the Northwest, valid from midnight tomorrow night to 1100 Tuesday. As the colder air filters southwards on Monday night, so scattered wintry showers (soft hail/sleet/snow) will blow in off the Irish Sea, especially after midnight and at first on Tuesday morning. Wind direction is critical in determining which parts of the region are most exposed but the latest forecast suggests the southwestern quadrant of the region (W Cheshire, Merseyside, SW Lancs) is most at risk from showers which, as the warning states, could result in a little lying snow, chiefly on ground above 200m. Perhaps of greater importance than any snow though will be the risk of ice around rush-hour on Tuesday morning as roads and pavements, wetted by the showers, are further chilled in the colder air with a consequent risk of ice.
By Tuesday lunchtime the shower risk looks to be over and attention then focuses to the northwest from where a belt of rain and freshening winds are due in on Tuesday night. The rain may be preceded by a little sleet or snow, especially at higher levels. However, no significant issues are expected with this. As the low pressure centre responsible for the rain/wind slips away into the continent late Wednesday/early Thursday cold NE’ly winds will prevail, perhaps bringing a few non-disruptive wintry flurries, mainly to Pennine areas. Thereafter the signal is for high pressure to build in and give us some fine, frosty weather towards the end of the week.
In summary then, watch out for icy patches first thing Tuesday and perhaps a little snow higher up, nothing like the OTT headlines posted by some of the tabloids and all well within the bounds of what can be reasonably expected in the second half of November.
The usual reminder that all warnings and the progress/development of precipitation can be monitored either on the Met Office website.
In the meantime have a good rest of weekend,
With kind regards,
Alan Goodman; Met Office Advisor (Civil Contingencies)