Author: Eric Gilbert

Once again it was warmer overnight than the previous day. That was thanks to the Tropical Maritime Air stream replacing the Arctic Maritime air that had brought the cold. The thermometer rose to 6.8C at 14.14 on Monday then dropped away to a low 5.5C at 17.45. At that time the effects of the arrival of the warmer air stream were observed as the thermometer began to slowly recover and rise to a maximum of 9.7C at 08.00 on Tuesday. Drizzle was conserved at 16.00, ahead of the warm front from increased cloud cover that produced 0.6mm of precipitation.

At first light on Tuesday, in addition to the warmer air, it was very humid with 100% humidity logged at 08.00 that had produced foggy conditions limiting visibility in Marlborough to 200m.

The centre of the anticyclone is now over the Bay of Biscay with the air circulating clockwise feeding the warm, moist air, now on a very light westerly.

The Polar Maritime Air that covered the country on Sunday, it originated near Iceland and Greenland, was very cool with the thermometer struggling to reach a maximum of 6.2C at 14.42 being 1.8C below the average. Not surprisingly, a cool night followed that saw the thermometer sink to 3.2C at 07.50 early Monday being 0.8C above the average. It was a dry day with just minimal UV light to trigger the sensor at 0.5.

Monday after dawn revealed a sky covered with thin cloud allowing minimal brightness, better than the recent gloomy days, but no sunshine. Thankfully the recent very strong winds have subsided so minimal wind chill, although feeling cold outside.

As the day progresses, the cloud will thicken as a warm weather front approaches and crosses the UK late Monday. This will result in the temperature rising during the late evening and overnight with some possible precipitation, but not white.

The barometric pressure has risen a significant 20mb over the past twenty-four hours as a very high pressure system mid-Atlantic begins to influence our weather allowing much milder weather to arrive on Tuesday for a few days over Christmas. This will allow a wedge of Tropical Maritime air to flood the country.

The drizzle and light rain coming from the thick low cloud on Saturday was a gloomy period for much of the daylight hours. The modest wind from the west allowed the thermometer to rise to a maximum of 11.6C at 14.05 being 3.5C above the average. However, just after 14.30 brief breaks in the lcd appeared and Hirt bursts of thin sunshine redeemed the day. The minimum of 3.3C overnight occurred at 06.35 early Sunday being 0.9C above average. The drizzle and light rain amounted to 2.8mm taking the monthly total to 55.2mm when the long-term average is 94.0mm.

Thin cloud greeted the new day on Sunday that brought a bright start with the hope of some weak sunshine when the sun rises above the horizon for a few hours and a dry day. The air today is less moist coming from the west-northwest air stream with humidity at 08.00 reading 83%, the second lowest this month after 82% on the 8th, when the wind was very strong and from a northerly quarter.

The wind today has been increasing after a strong gust of 29mph at 02.08 early Sunday. The average ten minute wind speed has increased by 4mph during the past hour, currently averaging 9mph. Once again we are being squeezed between a deep low pressure, now heading between Scandinavia and the Low Countries, and an intense high pressure just north of the Azores. This will see the wind coming from the west-northwest and probably more northwesterly this evening and gusting strongly.

The maximum of 8.4C at 15.31 on Friday was just above average at +0.3C but dropped away overnight to a low of 3.6C at 02.03 early Saturday being also just above average at +0.1C. A little rain fell just before 06.00 on Saturday morning amounting to 0.9mm

Saturday began very dark under thick, low cloud with a brisk westerly breeze with more rain likely during the morning.

A rapidly deepening depression is travelling east and currently positioned just north of Scotland with a very low pressure centre of 950mb and continuing to fall. Our pressure reading at 08.00 was 1014.4mb, also falling rapidly. This low pressure system will influence our weather over the weekend with more rain and very strong winds.

The thermometer struggled to reach a maximum of 5.3C on Thursday in the very brisk northwesterly breeze being 2.7C below the average. It was even colder overnight under clear skies initially, with a minimum of 1.3C at 01.47 early Friday that produced a ground frost. This low was 1.1C below average. It was a dry day with sufficient UV light to just trigger the UV sensor.

Friday after dawn revealed some broken cloud but it soon filled in before 08.00, with the thermometer having risen to 2.6C.

The soil temperature at a depth of 5cm had dropped to 2.0C by 08.00 as a result of the recent very much lower air temperatures by day and night.

The high-pressure continues to drive our weather, the barometric pressure having risen 15mb since yesterday, to 1022.0 mb by 08.00, with the wind having backed into the southwest and then west later in the day before increasing in strength over the weekend.