Monday 4th May
The forecast possible shower activity, light or thundery, did not occur over Marlborough on Sunday, although it was very close. Showers by their nature are hit and miss over small areas. A major shower did develop between Marlborough and Swindon at 18.30 and was heavy for over an hour until around 19.30, a few spots were observed just after 18.30 being on the southern flank of the shower area. Cloud began to thicken just before 15.00, resulting in weaker sunshine with a maximum of 18.4C at 17.20 being 1.1C above average. The past night was very mild with the thermometer not dropping below 11.2C at 05.00. Much of the light rain that fell on Saturday was lost into the atmosphere, evaporation from the ground and plant life was equivalent to 2.8mm of rainfall.
The UV level on Sunday rose to a value of 5.2, the highest since 1st September and well into the ‘High’ category.
The start to the new day on Monday revealed that very thick low cloud had formed in the early hours and in fact produced light rain starting just before 03.00 amounting to 1.8mm. The visibility at 08.00 was around 800m. Pressure is beginning to build again from the west with a reading of 1013.4mb at 08.00, however for much of the week the main area of the anticyclone will be to the west of the UK so no warm, dry spell ahead.
The week ahead will be unsettled and much cooler than last week. For much of the week low pressure will be to the east of the UK and a developing high pressure to the west, thus a wind today coming from the northeast, then north predominantly on Tuesday and then settling from an easterly quadrant for Wednesday onwards, towards the weekend. This will be a cooler air stream resulting in temperatures being depressed, probably just below average for much of the week and very cool on Wednesday under total cloud cover, likely wafted in from the cool North Sea, with little prospect of any sunshine.