Northerly on Wednesday meant another cool day

Although the wind on Wednesday had backed from the very cold northeasterly to northerly and dropped significantly in strength it was another cold day. It didn’t feel quiet so cold as the wind had dropped to a peak gust of 11mph compared to the 40mph+ previously, so there was no wind chill. The thermometer refused to rise above 8.8C, which was a significant variation on the 36-year average being 5.3C below.

It was a dry day with the UV level again at the top of the ‘Moderate’ range.

The barometric pressure has been dropping for the past forty-eight hours as the anticyclone lost its grip and the wind on Thursday now coming from the northwest, a less cold direction.

At least the cloud overnight prevented any frost forming with a minimum of 5.2C being 1.2C above the average.

Thursday arrived predominantly cloudy with the occasional bright spell, if brief.

March 2020 Review

A change in the month and thankfully a brief change in the weather as the beginning of March brought far less rain and a dry day on the 3rd. However by the 4th the unsettled weather returned with twelve consecutive days when rainfall was recorded.

The wettest day of the month occurred on the 9th with 15.6mm of precipitation.

On the 15th a high pressure developed over the Azores producing two dry days and higher temperatures. The south-westerly wind meant the milder air raised the temperature to 14.7C on the 24th, which was 4.3C above the 36-year average making it the warmest day of the month.

By the 20th an anticyclone developed over Scandinavia bringing cooler but more importantly drier weather. After days with minimal sunshine, or none at all, we enjoyed many hours with the sunniest day on the 25th that produced 9.85 hours of strong sunshine making it the sunniest day since 21st September.

As the Scandinavian high eased away an intense high-pressure system developed over the North Atlantic bringing cool north-easterly winds and dry weather. There were 10 consecutive dry days from the 20th, in contrast to the previous very wet months, making it the driest continuous period since the beginning of July.

The rainfall for the month amounted to 58.6mm making this the first below average month since July 2019. The total was just 1.2mm below the 36-year average. The wind and strong sunshine produced significant evaporation, especially at the end of the month. During this period 2 to 3mm of equivalent rainfall was evaporating into the atmosphere every day from the ground and plant life. In fact the total evaporation of 50.9mm was not far below the rainfall total of 58.6mm.

Temperatures throughout the month were variable, alternating between warm and very cool days. A maximum of just 5.1C was recorded on the 5th being 5.3C below the average.

The mean temperature was just 0.2C above the 36-year average. Analysing the data I found that the average maximum was 0.6C above average whereas cold nights meant the average minimum was 0.3C below average.

The anticyclones also produced days with strong winds, the 28th and 29th come to mind with maximum gusts of 40mph and 43mph respectively. There were 7 days when the wind gusted over 30mph. The wind strength and direction produced wind chill on a number of days, particularly at the end of the month when it felt 2C to 3C below the temperature indicated on the thermometer. North easterlies are common during March but this year saw 12 days
with winds coming from that direction, an unusual proportion for the month.

There were 7 days when frost was recorded and 2 days when small hail was observed.

The end of the month brought us 12 days with just 0.1mm of rainfall. During this dry period many hours of strong sunshine were recorded with in excess of 9 hours on each of five days. The solar energy for March was 118% of the 11-year average.

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