Windrush Weather

Tuesday brought a wintry day with the first snow flakes observed at 09.05 and heavier, continuous snow at 10.45. The total precipitation amounted to 3.7mm that took monthly total to 25.5mm compared to the 40-year average of 91.7mm. It was observed that snow began to settle on the grass at 11.00, a slow thaw began late afternoon after the snow had stopped falling.

The thick cloud, modest northerly breeze later in the day and snow meant a cold day with the maximum of 2.1C at 08.00C but wind chill outside meant felt at least 2C colder. By 11.30 the thermometer had dropped to 0.8C. During the evening the thermometer dropped to 0C at 21.10 with a minimum of -2.2C at 06.11 early on Wednesday, which was 6.3C below my 40-year average.

The start to Wednesday revealed variable cloud but some brightness with the possibility of sunshine later. The temperature had recovered a little to read -1.2C at 08.00.

The soil temperature at a depth of 5cm read 1.3C at 08.00, a drop of almost 5C since that time on Tuesday and far below the 11.0C logged on the 3rd.

Monday started with a temperature of 5.2C at 08.00 and hovered around 8C for much of the day, however, in the evening an area of much warmer air arrived that lifted the maximum to 11.2C at 00.15 very early on Tuesday, which was 0.9C above my 40-year average. After stabilising around that temperature for a couple of hours a cold front arrived that saw the temperature then dive to reach a minimum of 2.1C at 07.51. During this period, that accounted for the drop in temperature, the air stream began to veer from the west into the north.

The first light rain was observed falling at 12.05 on Monday, but became heavier after 14.15 and continued during the evening and early hours and heavy just after 05.00 Tuesday.

The barometric pressure fell rapidly during the night dropping from a pressure of 1012.9mb at 08.00 on Monday to 997.5mb at that time on Tuesday as the centre of the depression was over southern England. The low was 995.8mb, which was the lowest pressure since 9th October (986.3mb). The wind was brisk in the early hours producing a wind chill that meant it felt more like 0C outside.

Tuesday struggled to come alive under thick, low cloud and light rain or drizzle. The rain band is extensive and is likely to produce more precipitation during the morning, hopefully not white!

Update at 09.05: Temperature dropped to 1.7C and snow flakes observed falling.
10.45: Large flakes in heavier fall with the temperature reading 1.3C
11.00: Snow beginning to settle on grass in zero air movement
11.30: Temperature dropped to 0.8C

Sunday gave us a very welcome sunny morning but cloud began to build after midday and totally obscured the sun late afternoon. The limited sunshine hours, combined with the brisk, cool wind from the west gusting ti 14mph, resulted in the thermometer only reaching a maximum of 9.9C just before midday at 11.55 being 0.4C below my 40-year average.

A cold front produced sporadic rain after 19.15 Sunday evening but more persistent and heavier rain arrived just after 23.30 amounted to 6.9mm, which took the monthly total to 8.5mm when the 40-year average is 91.7mm. This was the wettest day since 18th October.

The cold front meant that the thermometer fell away in the early hours of Monday to reach a low of 5.2C at 08.00, which was 1.2C above the average.

Monday revealed radiation fog forming in the River Og valley just before 07.30 as the temperature continued to fall. The fog had all but dissipated by 08.30 although the thermometer had dipped further to reach 5.0C at 08.25 before starting to recover.

A mini low has recently formed to the west of the UK and will travel over southern England as the day progresses and bring more continuous rain later this afternoon.

Saturday was the last of the mild days and nights for a few days that saw the thermometer rise to 10.8C at 12.38 before the cold front passed our way and was 0.5C above the long-term average. The cloud cover persisted all day and night limiting the loss of overnight warmth into the atmosphere, as a result the minimum of 6.3C logged 07.55 early Sunday was 2.3C above the long-term average.

It was another dry day with just 1.6mm the total rainfall for the first half of November when the 40-year average is 91.7mm.

Sunday after dawn revealed another morning with total cloud cover but mild and calm, the breeze having veered into the west that will persist for most of the day.

The high pressure has fallen away further so we are beginning to come under the influence of a low pressure system over Scandinavia that will soon bring much cooler weather from the north for a few days. The barometric pressure reading at 08.00 was 1017.5mb down almost 20mb since its peak six days ago.

The temperatures were below average on Friday, even before the cold front arrived today. The thermometer reached a maximum of 7.9C at 13.27 being 2.4C below average while overnight it fell way to a minimum of 1.8C early Saturday at 04.53, which was 2.2C below average.

Friday arrived with total cloud cover and a trace of radiation fog in the River Og valley due to the low overnight temperatures as the moisture in the air condensed. The temperature had recovered slightly to read 4.4C at 08.00.

The cold front will pass over our area today heralding a change in our weather for the next few days although for most of the day the air will come on a southwesterly breeze veering into the northwest later in the day. The recent anticyclone has lost another 14mb since Monday with a. reding of 1021,2mb at 08.00.