Gloucestershire Weather

From about 4am today (20th Jan 2010) heavy rain began to fall in air temperatures of about 4c.

Then the temperature slowly started to fall. But after 6am the temperature started falling quicker and by 7am this rain had turned to heavy snow.

A graph from my weather station showing the temperature drop, look from 4am to 8am.

The purple line is the temperature, the red line is the dewpoint and the green line is the wind chill.

I was amazed at how quickly the snow settled considering the 3hrs previous rainfall.

It left about 2cm on the ground before it stopped and then began melting quickly in temperatures that rose to 2.7c at 4pm.

Overnight here in Frampton-on-Severn, the temperature fell to an all time low of -11.5c.

Temperatures will not rise above 0c all day and will fall to a similar level again tonight, or even lower.

A very severe cold spell.

All last week we were forecasting either thundery rain or thunderstorms to develop on Monday 25th May, but there was uncertainty about this from the start as the forecasting models couldn't agree on the outcome.

The GFS (Global Forecasting System) continued to forecast a thundery breakdown, even on Sunday, starting in the SW on Monday morning.

But the plume of unstable air, which produced the thunderstorms forecast to travel North into this area actuallly travelled in a NNE direction taking it away from this area.

The SE of England did have some thunderstorms but they quickly travelled out into the north sea.

This was a difficult senario to forecast so it was always at risk of being wrong.

So we missed the thunderstorms, but was that a good or bad thing?

Still time for plenty of thunderstorms this summer

This afternoon the temperature breifly popped up to 18.8c making it the warmest day of the year so far.

It started off cloudy but once the sun came out the temperature shot up.

More warm weather expected during the week