Author: Eric Gilbert

The air from the Atlantic, brought on a westerly breeze on Monday, saw the thermometer rise a little higher than previous days but with a maximum of 17.1C was still 1.6C below the 36-year average. The loss of sunshine as the clock struck 11.00 brought increasing cloud that limited any further increase in temperature.

The day was dry until late evening as between 22.15 and 23.00 light rain fell and also a light shower early on Tuesday morning that produced 1.0mm of rainfall. September is still a very dry month as the total rainfall amounts to just 15.4mm, which is 47.5mm below the 36-year average. The other factor to take into account is the equivalent loss of moisture into the atmosphere due to evaporation that currently stands at 59mm, a deficit of 45mm.

The past night was mild with the thermometer not dropping below 15.4C until between 02.45 and 03.00 when the wind suddenly picked up and veered from west to northwest. The thermometer then started to fall in the cooler air reaching 12.3C at 08.00 on Tuesday.

Dawn on Tuesday was overcast due to cloud from the back edge of the weather front that passed through overnight. The wind is light and continues from the north west.

Sunday brought us another day with over eight hours of sunshine that meant a slightly warmer day than previously with a maximum of 14.8C but this was still 3.9C below the 36-year average thanks to the cold air from Scandinavia. The wind, though still from the north-northwest, was just a little lighter but still with a maximum gust of 24mph.

The wind fell out almost completely around 19.00, that combined with a clear sky, gave the indications of a cold night to follow as any warmth would quickly escape into the atmosphere. That proved correct as the thermometer fell steadily downwards to reach a minimum of 0.6C at 07.12 on Monday morning that produced a ground frost. This was the coldest night since 15th May.

Monday dawned with hazy sunshine initially due to thin, high cloud on the eastern horizon but shortly after 07.45 the sun gained in strength and shone continuously. The thermometer had recovered to 2.6C at 08.00 but with the later arrival of the sun in late September it was the coldest start to the day at that time since 14th April.

The overnight charts show a significant change in wind direction. From around 05.00 the air mass began coning from the west bringing Atlantic air so a warmer day in prospect.

Saturday was even cooler than previous days as the wind from the north northwest persisted all day, not quiet so extreme as on Friday but
still gusting to 26mph. This meant the thermometer struggled to reach a high of 13.0C, which was the coldest day since 13th May and 5.7C below the average for September.

The past night also saw a below average minimum (-1.6C) with a low of 7.6C.

Sunday arrived with variable cloud but just before 08.00 there were brief bright intervals. By 08.15 the sun was beginning to shine more strongly and for longer. The wind still persists from the north northwest so that there is a wind chill that makes it fell at least 2C below that registered on a thermometer.

The depression just to the east of the UK brought the Arctic plunging down across the country on Thursday with very strong winds. The wind increased all morning with a maximum gust of 37mph that was recorded at 13.05. It was a dry day as the barometric pressure was beginning to rise damping out any shower activity.

Temperatures by day and night were again depressed due to the cool air with a maximum 14.1C being 4.6C below average and with clear skies overnight a minimum of 4.3C just after dawn, which was 4.9C below average.

Saturday saw the sun greet the morning as it rose above the horizon and was soon shining strongly and continuously.

On Thursday the wind for most of the day was from the south west or south south west gusting to a peak of 22mph. Early evening the wind dropped out entirely giving calm conditions. The barometric pressure was at its lowest since 30th April with a low 992.2mb at 17.54. As the centre of the depression began to ease away the wind began to pick up and the pressure to recover so that just before midnight the wind backed dramatically coming from the north.

Due to the arctic air mass the temperatures have been depressed over the past twenty-four hours. Initially, in glorious sunshine on Thursday morning, the thermometer rose to 13.7C at 11.28 but increasing cloud meant that this was the maximum, which was 5C below the 36-year average. With clear skies until just before midnight the temperature dropped steadily to give a chilly minimum of 3.3C at 23.23, which was 5.9C below average. Cloud then restricted any further fall.

It was the coldest day since 13th May and the coldest night since 15th May.

Friday saw thin cloud cover from dawn but just after 08.30 a little brightness was observed as the sun began to rise above the cloud bank and strengthen. The wind has backed a little further, now from north north west.

At 09.00 the thermometer had struggled to reach 6.7C with a wind chill that meant it felt more like 4C as the wind was gusting to 20mph. However, by that time the sun was gaining in strength.

Update on Friday at 16.10: peak gust of wind measured 37mph at 13.03 making it the strongest wind gust since 25th August.