Another frosty night

With just 15 minutes of sunshine on Thursday and a brisk northwesterly wind, it was not surprising to find the maximum temperature was again below average, just, with a peak of 9.7C (-0.4C).

A clear sky overnight saw the thermometer fall below zero just after 20.30 and reach a minimum of -2.0C at 04.14 this morning.

Friday arrived with the sun shining strongly as it rose above the horizon triggering the recorder at 07.50. By 08.00 the thermometer had risen to -0.8C.

Review of October 2018

October brought us another month of contrasts with some daytime temperatures more likely to occur in August whilst at the end of the month we briefly endured a severe frost that was a record and more likely to be seen in the months of January or February.

The mean temperature for the month was 0.6C below the 34-year average, principally due to cool nights. The daytime mean was 0.5C above average whereas the night mean was 1.6C below average.

The second week saw two days that reached maxima in the 20’s with 22.4C and 21.3C on the 10th and 13th respectively. In contrast the during the early hours of the 31st the thermometer fell steadily to a minimum of -4.3C, this was a record for this station set up in 1984 and equals the same minimum that occurred on 30th October 1992.

A record for the coldest October day since the station began in 1984 was set on the 27th when the thermometer resolutely refused to rise above 5.2C due to strong northerly winds. The October average maximum is 14.7C.

Another example of our variable weather can be seen in that the mean for October 2018 was 9.87C, but in 1992 we experienced a very cool month with a mean of just 6.95C whereas a balmy October occurred in 2001 when the recorded mean was 12.77C.

Turning to rainfall, we have experienced the fourth consecutive below average October rainfall. The total for the month was just 44.6mm, which was 53% of the 34 year average or 40.2mm below. The wet October of 2004 produced 159.3mm whereas the very dry October in 2017 gave us only 31.3mm when the average stands at 84.8mm.

There were two very wet days on the 14th and 15th with 12.7mm and 14.8mm respectively. However, we enjoyed 22 dry days when the average is 14 dry days.

My sunshine recorder was only installed in 2014. October 2018 was a very sunny month as we enjoyed 130 hours of strong sunshine (<100watts /sq.m.) that contrasts with the average for the previous four years of 73 hours. Still on the theme of contrasting weather, the diurnal data for October shows just how much we as individuals have to adjust on a daily basis. The minimum temperature variation between day and night on the 6th was just 2C whereas a range of 17.3C occurred on the 31st as the severe frost rapidly cleared during the morning as a gentle southerly air mass arrived. This quotation from Percy Shelley sums another colourful season: “There is a harmony in autumn, and a luster in its sky, which through the summer is not heard or seen, as if it could not be, as if it had not been!” Update at 16.20 on Friday: almost 8 hours of sunshine and light winds lift temperature above average (+0.7C) to maximum of 10.8C.