Category: Commentary

Friday brought much more snow drifting in the strong winds and a temperature of around -2.0C most of the day.

As late evening set in the thermometer began to rise so that at 23.00 it was reading -1.2C.

This morning it is foggy, with visibility down to 500m, as a gradual thaw sets in with the temperature of 0.8C when readings were taken at 08.00.

Saturday update at 12.30: thaw well and truly under way. Temperature 2.7C, being the warmest day for a week.

Saturday update at 17.00: After a peak of 3.9C at 14.32, the thaw is diminishing as the temperature falls to 2.8C with rain now beginning to fall.

Storm Emma made itself felt on Thursday with sustained strong winds, frequently gusting to 20mph-30 mph, producing a wind chill of -9C. The thermometer hovered around -3.1C all day but late afternoon and evening eased upwards to -2.0C.

Snow fell for most of the day, light and dry, that in the strong winds caused blizzard conditions and considerable drifting.

The snow eased off over night so that today it is cloudy with the wind rising again, peaking at 37mph. No further snow has fallen since dawn.

Friday update at 11.15: temperature -1.9C and wind chill -7C. No new snow this morning, just occasional flakes in the air and what looks like light drizzle earlier but likely to be freezing rain – not venturing out to check!

Friday update at 13.00: heavy snow just started. Temperature-2.0c, wind chill -8.1C.

Friday update at 15.30: wind over last three hours beginning to fall a little lighter, dropping about 5mph on earlier gusts, as barometric pressure begins to rise again as storm Emma eases away. Temperature still -1.9C and wind chill dropped to -7C.

Update at 21.00: temperature rising gradually as milder air eases northwards, now up to -1.6C, warmest for three days.

Summary for February 2018 and Winter 2017/18

FEBRUARY
Winter returned with a vengeance in February. There was a brief mild spell during the third week but on only eight days did the maximum exceed the 34-year average. This day occurred on the 19th when the thermometer rose to the dizzy heights of 10.9C, being 3.6C above the average. In contrast the thermometer did not get above freezing on the 28th with a maximum of just -1.2C.

For exactly half the month there were air frosts of some degree, some very hard, with the coldest night occurring on the 28th when the thermometer dropped to -9.8C. Therefore it is not surprising to find that the average temperature for the month was 2.2C below the long-term average. It was the coldest February since 1991 and the 4th coldest since 1984, when this station began recording, only 1985, 1986 and 1991 being colder.

The last week of February was bitterly cold. The stratospheric warming of the higher atmosphere temporarily reversed the flow of the Jet Stream so that instead of winds coming from the west, for eight days they came from the northeast bringing cold air direct from Siberia. Adding to the cold were the strong winds gusting between 20 and 30mph producing wind chill that at the end of the month meant it felt more like -11C.

It was the second consecutive month with below average rainfall. A total of 54.9mm of precipitation was recorded being 10.3mm below the 34-year average. Over half the rainfall occurred on two days with 13.2mm and 17.5mm on the 8th and 14th respectively.

The high pressure over Scandinavia that brought the northeasterly winds meant that we enjoyed many hours of sunshine on a number of days. I recorded 110 hours of strong sunshine (100w/sq.m.) during the month with 8.5 hours and 9.2 hours on the 24th and 25th respectively. That is almost twice the average over the past four years since this instrument was installed.

The soil temperature at a depth of 5cm averages around 3C for February but the exceedingly cold days and strong winds meant that frost penetrated deep into the soil. The average for 2018 was 1.4C with a reading of -1.7C on the 27th.

There were 5 days when snow flurries or showers were recorded, but no great depth of snow occurred.

WINTER 2017/18
The past winter was the coldest for five years being 0.3C below the 34-year average. January was 1.2C above average but February being 2.2C below meant that overall it was a below average temperature season.

Rainfall for the past winter was again below average, the second successive drier than average season with 244mm in total being just 4mm below the 34-year average. The past two winters have now shown a deficit of 97mm of rainfall, which is much needed to refill the aquifers.

After the previous dismal winter, when just 121 hours of sunshine were recorded, the past winter total was 213 hours.

Wednesday saw the arrival of the forecast Siberian air when, after a hard frost and a low of -5.3C, the thermometer did not get above freezing all day. The maximum at 13.03 was -1.1C with wind chill making it feel more like -6C. This was the coldest day since 6th December 2010 when the thermometer only rose to -2.2C

The thermometer then began before falling again all afternoon to -6.1C late evening at 22.30 with a wind chill that meant it felt more -13C.

There were occasional light snow flurries during the day but nothing settling on the ground.

The temperature recovered slightly after midnight rising to -5.1C at 08.00 this morning with a wind chill making it feel more like -11C.

Snow began falling heavily just after 07.30 this morning as storm Emma made itself felt, the barometric pressure having fallen 15mb in one day, predicting its arrival. The wind is still from the north east and gusting to well in excess of 20mph so there will be drifting snow as the day progesses.

Update at 11.00: temperature -4.3C and wind chill making it feel like -11C. Light snow blowing in strong wind, but no great quantity

Update at 13.30: temperature at -3.4C and wind chill at -10C. Frequent showers of light, dry snow adding to modest accumulations in little drifts from wind gusting to 33mph.

Update at 16.00: temperature crept up to -3.1C, the warmest today! Wind chill now -9C. More continuous dry snow and drifting in the strong wind.

Update at 21.30: temperature easing up to -2.6C although wind chill of -9C as wind increases in past hour.

The very cold Siberian air mass made itself felt on Tuesday when the thermometer briefly reached 1.1C at 13.51, during the sunny period between 1 and 2pm, then falling back to 0.7C for an hour or two.

These readings made it the coldest day since 16th January 2013 when the maximum day temperature then was -1.1C. It was the coldest night since the low of -13.0C on both the 11th and 12th of February 2012.

Just after 3pm the thermometer began to fall steadily for 10 hours plummeting to -9.8C at 23.00 before beginning to recover as cloud drifted across.

There was a brief snow flurry mid-morning but a heavy snow shower, lasting almost twenty minutes staring at 17.50, produced a snow depth 1.5cm.

This morning at 08.00 the thermometer read -4.7C with a mainly cloudy sky.

Update at 1030: temperature of -2.9C, some melting of overnight snow in bright sunshine.

Update at 11.30: temperature of -2.1C with wind chill making it feel like -7.1C

Update at 13.30; temperature of -2.1C with light snow showers, not settling. The maximum today was -1.2C at 13.03

Update at 16.00: ambient temperature of -3.1C, wind chill feels like -8.2C. Wind increasing in strength for last 7 hours now gusting to 30mph

Update at 18.30: temperature -4.6C, wind chill feels like -11C with wind gusting to 31mph

Update at 21.15: temperature -6.0C, wind chill feels like -13C.

N.B. Coldest February since 1991.

The Siberian air began to bite on Monday with the thermometer eventually, for just a few minutes, struggling to reach 1.4C at 13.39, which was 6C below the 34-year February average and the coldest day since 11th December.

There was significant wind chill making it feel 4C below the thermometer reading as the wind gusted frequently to over 20mph with a maximum gust of 26mph at 16.33.

The sunshine was much reduced from the exceptional total on Sunday with just 3.47 hours.

Clear skies overnight meant a hard frost with a minimum of -5.3C at 06.33 this morning making it the coldest night since 21st January 2017. Wind chill gave a reading of -8.1C just before 1am this morning.

This morning there is broken cloud with strong sunny intervals, the thermometer having risen to -4.3C at 08.00. The temperature of the ground at a depth of 5cm was -1.7C at 08.00.

Update at 11.00: temperature -1.1C @ wind chill -7.0C

Update at 13.51: maximum day temperature of 1.1C, now falling with wind chill -3.1C. No snow yet.

Update at 15.40: freezing again with air temperature at -0.1C and wind chill at -4C. One light snow flurry.

Update at 16.40: temperature -1.4C with wind chill of -6C. Longer snow showers of very light, dry flakes. Light covering on ground with blue sky following.

Update at 17.50: temperature -2.7C and wind chill of -6.1C with heavy snow falling and settling.

Update at 19.00: temperature -4.2C, wind dropped light and approximately 2cm of snow on ground.

Update at 21.00: temperature -8.2C and still falling. Coldest night since 11th and 12th February 2012