Author: Eric Gilbert

Although the worst of the very strong winds have passed there were gusts up to 27mph on Monday and the average wind speed over ten minute hovered around 12mph all day. The extreme gusts and lulls of Friday and Saturday have been superseded by more consistent winds without the extreme gusts. As a result of the cool northeasterly wind and thick cloud cover over the twenty-four hours, the temperature varied little by day or night with a maximum of 6.6C being 1.4C below average and a minimum 5.2C being 2.7C above average. Light drizzle over various periods amounted to 0.3mm.

Tuesday began where Monday ceased with very thick, low cloud and a persistent wind from the northeast. The pressure differential between the low and high pressure systems has been falling as a result the wind is very slowly beginning to drop with the average wind speed over ten minutes now down to 8mph from a high of 18mph on Sunday.

The cool, strong wind is once again producing a wind chill so that the temperature of 5.2C at 08.00 outside felt more like 2C. Also the word having travelled over the North Sea is continuing to pick up moisture so although it is not likely to rain there will be variable drizzle from time to time.

The high pressure system has edged a little closer, as a result the barometric pressure read 1033.7mb at 08.00, the highest for a month.

Although the extreme winds gusting to over 40mph abated a little Sunday evening they were still strong at over 30mph. The strong wind and from a cold northerly direction meant a cool day with the thermometer not exceeding 6.9C at 22.35 being 1.2C below my long-term average. In fact those conditions produced a wind chill again in that when the thermometer read 6.1C in the evening the wind chill meant outside it felt more like 2C. The minimum of 4.9C was logged at 14.30 being 2.5C above average. The intermittent showers amounted to 3.8mm.

Monday revealed a day that was so similar to Sunday with the wind still gusting strong. However, there was one major variation. The very strong gusts, then brief lulls, on Sunday had given an average speed over ten minutes of up to 18mph whereas on Monday the very strong gusts had dropped away with gusts up to 25mph with more consistent wind strength around 15mph and still an average speed over ten minutes of 14mph.

The winds are the result of a squeeze between the high pressure centred off Ireland, circulating clockwise as they do, and the old depression now over the Mediterranean, circulating anticlockwise. The barometric pressure has risen another 12mb with a reading of 1032.2mb at 08.00, the highest pressure since 14th November.

There is a lot of cloud again due to the airstream travelling over the North Sea picking up moisture along the way.

Saturday was memorable for the very strong winds, increasing during the evening and overnight gusting to 45mph at 02.15 early Sunday. The wind from the northwest gave an uninterrupted flow to my anemometer above ridge height. The thermometer reached a maximum of 11.3C at 13.03, which was 3.2C above my 40-year average. From that time the temperature slowly fell away dropping to a minimum 5.5C at 05.40 early Sunday.

The intermittent brief showers amounted to 6.5mm that took the monthly total 30.5mm, being 32% of the long-term average.

Sunday was a continuation of the very strong winds although showing a slight drop off in strength, the 10 minute average speed had dropped from 18mph on Saturday evening to 12mph Sunday morning. The drier winds from the north-northwest was shown in the humidity reading of 82% at 08.00, the lowest at that time since 4th July. The wind will veer a few more degrees into the north as the day progresses.

Storm Darragh has been slowly receding, now over the near continent, and becoming under the influence of a high pressure in the eastern Atlantic, shown by the barometric pressure rising to 1019.8mb at 08.00, up a significant 28mb. A rise of over 20mb in twenty-four hours is unusual.

Initially the advance weather from Storm Darragh saw the thermometer steady around 7C for much of the daylight hours on Friday but began to climb in the evening reaching a maximum of 12.4C at 23.45 being 4.3C above the average.The temperature then began to fall as a result of the wind veering from southwest into the west and then north-northwest dropping the temperature to a low of 6.4C at 08.00 Saturday. The wind strength was rising all the time and peaked at 41mph at 03.48.

N.B. My weather station is in the lee of higher parts of Marlborough when the wind is from a southwest quarter, although the anemometer is well above ridge height on my bungalow. There have been sporadic brief showers amounting onto 2.7mm. The wind chill at 08.00 meant it felt at least 2C colder outside than indicated on the thermometer.

During the evening the barometric pressure was dropping 3mb every hour as the depression closed in on our area. The pressure reading at 08.00 Saturday was 992.2mb, which was down a significant 34mb since the peak on Wednesday.

The start to Saturday revealed thick, low cloud and sporadic rain again as the wind strength had begun to fall slightly, but was still very strong.

The centre of Storm Darragh is crossing the country and will be over the east coast by midday when conditions will very slowly moderate but still strong wind gusts.

Thursday was another day that started calm, dry and dull but rain arrived in the mid-afternoon with the wind increasing producing strong gusts at 17.40 up to 25mph. The daily rainfall amounted to 8.5mm that took the monthly total to 21.3mm against the average for December of 94.0mm. The temperature at 08.00 was 12.8C but dropped away during daylight hours and after the rain band clear around 19.00 the rain stopped, the wind abated and the temperature began to fall away to reach a minimum of 3.4C at 07.51 early Friday. The maximum was 4.7C above average whereas the minimum was just 0.9C above average.

The barometric pressure has been rising overnight producing a short lived ridge of high pressure for the daylight hours of Friday. However, Storm Darragh is closing in. The centre of the depression at midnight was just west of Ireland but over the next twenty-four hours it will move eastwards across central England. Weather warnings have gone out for extreme wind gusts and more heavy rain.