Category: Commentary

The blast of cold air from the Ukraine and Black Sea area meant a cold day and night on Sunday.The wind from the north northeast, frequently gusting between 25 to 30mph, with a maximum gust of 35mph at 11.49, produced a wind chill. The maximum temperature of 3.4C was 4.3C below the 37-year average but the wind chill day meant it felt more like -1C.

The strong, gusty wind from the north east continued overnight as the thermometer fell away to a minimum of -2.4C whilst the significant wind chill meant at dawn that it felt more like -6.3C.

The humidity on Sunday afternoon and overnight has been restively low hovering around the low 80% instead of the usual high 90s, so it was not surprising to find that the light shower of snow in the early morning was dry, powdery snow blown around in the wind still gusting to 30mph. The melted snow from the funnel of the rain gauge amounted to 0.2mm of precipitation. This was the best estimate as the snow was blown around leaving some areas clear and others with a light accumulation as it drifted in the strong wind.

Monday arrived with broken cloud and occasional bursts of sunshine after 08.30 as the sun rose above the cloud bank on the eastern horizon.

The wind veered into the north just after dawn on Saturday but was very light for much of the day. The breeze from this direction is much colder and as a result the maximum of 7.4C was the first day this month the thermometer that did not climb above the 37-year average being 0.3C below. During the evening the wind strength increased a little but picked up strength in the early hours of Sunday with a maximum gust of 28mph at 05.35 and from the north east.

We did enjoy 3.7 hours of sunshine on Saturday, the sunniest day since 25th January, with the UV level inching upwards again with a peak reading of 1.2 being in the ‘mid low’ category.

There were a couple of very light showers overnight, the heaviest of which triggered the automatic rain gauge at 00.45. The daily rainfall, as measured in the Meteorological standard 5″ copper rain gauge was 1.4mm.

There was little evidence of this rainfall after dawn on Sunday due to the stronger, drier wind with humidity of 87% at 08.00 the lowest since the end of January. The sky was full of thick cloud driven on the north easterly wind that produced a wind chill so that although the thermometer read 1.6C at 08.00 it felt more like -1.4C.

During the 1.3 hours of sunshine on Friday the UV level rose to 1.1, last recorded on 6th November, evidence that in the brief sunshine the sun is slowly gaining in strength. The wind strength was often quite slack with a maximum gust of only 16mph and the air movement mainly from the south. The thermometer rose to a maximum of 9.4C being 1.7C above the average.

With clear skies overnight the thermometer steadily fell away to a minimum of -2.9C at 07.53 on Saturday. This low was 3.5C below the 37-year average minimum and the coldest night since 26th January (-4.0C). The drop in temperature and high humidity from the recent rainfall produced fog that at dawn limited visibility to 200m.

After sunrise on Saturday the sun began to interact with the weather through the fog and by 08.30 had improved visibility across the Marlborough Downs to 1500m but only to 300m across the River Kennet valley.

The maximum temperature on Thursday was down a little again with a peak of 9.0C at 15.16 but it was still 1.3C above the average.

There was considerable rainfall, starting just before noon, amounting to 7.2mm that brought the monthly total to 14.4mm when the average is 67.2mm.

The cloud cover overnight meant another above average minimum (+1.7C) with a low of 3.2C at 07.02 on Friday. Radiation fog appeared briefly in the River Og valley around dawn.

Friday started with a little brightness after dawn but the sky continues to be completely cloudy at -09.00 in calm conditions, after the southerly breeze on Thursday.

The mild air still over the south of the country meant another above average day on Wednesday with a maximum of 9.7C at 13.14 being 2C above the 37-year average but down almost 3C on the Tuesday high. A brief light shower in the early afternoon amounted to 0.3mm.

Although the thermometer fell away overnight the minimum of 2.4C at 04.44 was 0.9C above average but recovered to 4.8C at 08.00 on Thursday. The low was 4C below the Wednesday minimum.

Thursday dawned grey and dull with low cloud and fog that limited visibility at first to 200m. The mild air is likely to continue for Thursday as the wind has backed further, now from the south, with little movement of air at 09.00.

The rain radar shows an extensive shower area approaching the south cast that is likely to arrive at or soon after noon.