Category: Commentary

The air stream on Sunday was predominantly from the west, which is a warmer direction than from a northerly quadrant as occurred recently, so it was not surprising to find the maximum was the highest since the 20th, but not by much as the ground has been cold. The peak of 12.4C was logged late in the day at 17.34 due to afternoon weak sunshine that followed a damp overcast morning, but this was still 1.7C below my 40-year average. The light rain and drizzle amounted to just 0.3mmm taking the monthly total to 78.0mm being 137% of my 40-year average.

After so many damp and gloomy mornings it was a pleasure to see the sun shine on Monday morning, if variable, through thin cloud. The next depression is off the west coast of Ireland so advance cloud will build up as the day progresses and reduce the sunshine. Just after midnight, the light airstream showed that the wind had backed further and was coming from the south due to the position of the new low pressure system. This is a much warmer air stream and this morning outside it felt much pleasanter than the cold winds of recent days. The barometric pressure has recovered 12mb having risen to 1014.2mb at 08.00, the highest pressure for five days, so it should be a predominantly dry, if cloudy day as it progresses.

Saturday is best forgotten being cold and wet. The light rain petered out mid-morning. The thermometer did not even rise into double figures with a maximum of only 9.2C at 16.44 that was 4.9C below average. Light rain from the extensive weather front crossing the Channel was first observed at 19.10 with more intense rain arriving at 19.50 and continuing all night only easing just before 08.00 on Sunday. The daily rainfall amounted to 23.1mm, which was the wettest day since 23rd March and took the monthly rainfall total to 77.7mm, which is 20mm above my 40-year average.

Sunday revealed a dull and wet start to the new day as the last of the rain lightened and stopped. The depression that crossed the English Channel yesterday was at 08.00 centred over the London area. As it moves northeastwards into the North Sea, the wind, which has already backed from northeast to northwest, will back further into the west then southwest. This heralds a change in our weather for next week with temperatures beginning to recover to normal or a little above.

Thankfully Friday was dry until just after midnight whilst the muted sunshine lifted the temperature to a peak of 11.7C at 14.02 before the cloud began to build. The breeze was brisk and from the east, a cold direction, thus another maximum that was below average (-2.4C) for April. The low overnight of 4.2C was logged at 02.51 before once again the cloud thickened as another weather front arrived.

Rain first triggered the automatic rain gauge at 01.30 and by 08.00 amounted to 9.5mm in the 5″ Met Office copper rain gauge, taking the monthly total to 54.6mm, just 2.5mm below my 40-year average.

Daylight on Saturday morning, such as it was under thick cloud and low light levels, as the rain continued to fall. The cold northeasterly and continuous thick cloud and later rain will mean a cold day with the thermometer unlikely to get into double figures.

The centre of the depression at midnight was over the Bay of Biscay but as the day progresses it is forecast to move northwards into the English Channel. As it closes in on the UK the associated fronts, two of them, will bring more rain later this afternoon and into the night with the wind increasing and from the north east.

The low pressure systems surrounding the UK gave us another dull and dreary day on Thursday with a damp morning and dull afternoon amounting to just 1.0mm. The thermometer struggled to reach 11.8C at 12.26 being 2.3C below my 40-year average. The low temperature overnight was just above average (+0.7C) with a minimum of 4.4C logged at 01.57 early Friday.

Friday arrived with a little brightness around 08.00 but no sunshine. Another dull day is ahead with the nearest depression to the southwest of us, its centre is just of the southwest approaches, throwing cloud across our region with its associated weather front.

I counted five low pressure systems surrounding the UK this morning with their associated cloud that will produce another cool day, especially as the wind is now coming from the east, a cold direction. The barometric pressure has now sunk to 1003.6mb, down 27mb since the high on Sunday.

Sadly, the large area of low pressure is forecast to hang around until after the weekend so a few more dull, cool days with variable cloud are ahead.

Wednesday produced the fifth consecutive below average maximum with a peak of just 11.2C at 15.15 being 2.9C below the average. At least it was a dry day although the variable cloud meant the UV level was only ‘Moderate’.

The temperature slowly fell away in the evening that by 23.00 registered 1.7C and then no surprise to find it dipped below freezing for almost three hours with a minimum of -0.7C at 02.23 producing not only a ground frost but an air frost, only the second this month.

After the sun had risen above the cloud bank on the eastern horizon on Thursday it began to shine strongly just after 07.30 lifting the temperature to 5.9C at 08.00. However, shortly after 08.15 advancing cloud began to mask the sun. The wind has backed into the west overnight and will continue from that direction until late evening when it will come from the northeast or north-northeast.

Today we will be under a ‘trough’, which forms as the jet stream dips down and forms a bowl shape in the pressure gradient. It will result in cooler weather and rain that is likely around midday or shortly afterwards and likely to become heavy during the afternoon. The barometric pressure has fallen further, with a reading of 1007.0mb at 08.00,a drop of 24mb since its peak on Sunday. The wind fell light overnight, assisting the drop in temperature and is likely to remain light for much of the day.