Monday 11th May
Sunday was a very, very cool day, thanks to the very strong, cold wind from the northeast that continued to build in strength all morning and into the afternoon before falling away early evening, and fell out completely just after midnight. Mid-morning the thermometer read 11.1C on a radiation shielded thermometer whilst the wind chill meant it felt more like 9.9C outside. The increased cloud and disturbed weather was due to a cold front crossing the area around mid-day.
Due to the wind dying out, clear skies overnight and under the cold air stream, the temperature fell away steadily to give a minimum of -1.0C at 05.17 producing an air frost, in fact there were almost three hours of air frost with the thermometer dropping to -0.1C at 05.17 and not rising to 0.0C until 06.06. The low was a significant 8.0C below my May average.
Monday arrived with welcome sunshine that lifted the temperature to 8.9C by 08.00. Cloud will build late morning as another cold front works its way across our area. It is possible that it might contain light showers. At 08.00 the radar showed a large broken cluster of shower activity heading down from the north and just reaching Birmingham at that time. At 08.30 advance clouds could be seen to the north of Marlborough.
This morning on the surface pressure chart I counted four low pressure systems surrounding the UK in an arc from Greenland to Iberia with the Azores high having moved westwards towards America. The wind will vary considerably in direction today as these weather systems jockey for position moving from west-northwest to north and north-northeast before returning to north overnight. The next few days will bring variable conditions, with sunny intervals and possible light showers on Wednesday, which is likely to be a very windy day as another weather front crosses the country and at least two troughs of low pressure follow it producing disturbed weather. The week ahead will continue the recent pattern of depressed temperatures by day and night.