Snow fails to show up as temperatures rise overnight but weather warnings re-issued for this morning

The much talked about snowy weather expected in the region overnight failed to show up however: the Met Office has re issued its yellow warning for snow in Flintshire from now up to this afternoon.

We had a brief snow shower over Deeside at around 6:45pm and some flurries a little later on. 

SNOW SNOW SNOW…………. #uksnow CH5 2/10 #Deeside #flintshire

— Deeside.com (@DeesideDotCom) January 20, 2015

The Met Office and BBC has come in for a bit of a Twitter bashing (unfairly) as many people woke up this morning expecting to see 6ft snow drifts and eskimos in their gardens, taking to Twitter to complain about the ‘inaccuracies’ of weather reports.

The problem we had last night was warm air temperatures, meaning anything falling as snow had to fall through air temperatures well above freezing turning flakes into rain, you can see on our chart the overnight temperatures rose to a balmy + 2.6°C (see FYI section below on temperature complexities) however temperatures are starting to drop away slightly this morning suggesting we could see a little snow on higher ground.

Current yellow weather alert from the Met Office is valid until 12pm they say:

Further outbreaks of sleet and snow will affect parts of North Wales, the North Midlands and northern England this morning. Some areas have seen accumulations of 2-5 cm overnight, mostly above 150m but also at lower levels in places, and there may be further localised accumulations of several cm before the bands of snow become lighter and patchier later this morning. Total accumulations of 10 cm or more, including that already fallen, are possible over hills.

FYI:

Snow forms when the atmospheric temperature is at or below freezing (0 degrees Celsius or 32 degrees Fahrenheit) and there is a minimum amount of moisture in the air. If the ground temperature is at or below freezing, of course the snow will reach the ground.

However, the snow can still reach the ground when the ground temperature is above freezing if the conditions are just right. In this case, snowflakes will begin to melt as they reach this warmer temperature layer; the melting creates evaporative cooling which cools the air immediately around the snow flake.This cooling retards melting.

As a general rule, though, snow will not form if the ground temperature is 5 degrees Celsius (41 degrees Fahrenheit).