Apr 022013

Nationally, March 2013 was the coldest March for over 50 years, thanks to a stubborn high pressure system over Scandinavia, which diverted the jet stream over the Mediterranean. Atlantic low pressure systems were kept at bay by the high pressure block. Locally, March 2013 was not only the coldest recorded, but also the third coldest month on record. The month was also the windiest ever March, with a month record of 19 rain days.

The temperature averaged a mere 1.8°C, a full 3.7°C below the month mean. The highest temperature recorded was only 9.5°C on the 5th at 14:28, with the lowest temperature -3.7°C on the 14th at 05:44. On the 23rd, the temperature was -0.1°C at midnight which was the maximum temperature on the day. That made it the coldest March day ever recorded. The month started as normal with 6.2 hours of sunshine on the 2nd, before the month high on the 5th. Signs of what was to come were evident by the second week of the month when a cold easterly set in, forcing a drop in temperatures. There were 19 frost days in the month, beaten only by 20 days in December 2010, and cumulating in an unbroken run of 11 frost days from the 21st onwards.

The average daily maximum temperature was 4.4°C, and the average daily minimum temperature was -0.5°C. The average dew point of -0.4°C and the maximum heat index of 9.5°C were also March records. There were 74.6 hours of sunshine in the month, the best so far in 2013, but well down on the March 2012 total of 125.2 hours. March was, in fact, the sunniest month since September 2012, highlighting what a gloomy autumn and winter it has been.

Precipitation for the month totalled 31.8 millimetres, 4.7 millimetres more than the mean, but snowfall was to be the most significant weather event. A total of 25.3 centimetres of snow were recorded, slightly below the January total of 29.3 centimetres. On the 22nd, 4 centimetres of snow fell in the early hours with wind gusts of up to 30 mph. By 22:00, another 5 centimetres had fallen, and despite a slight thaw during the afternoon, the snow depth was 7 centimetres by dark. The snow continued to fall into the 23rd, with a further 11 centimetres. The snow depth was 14 centimetres by evening, with drifts up to a metre in places. Another 4 centimetres of snow fell in the early hours of the 24th, taking the snow depth to 18 centimetres. By the end of the month, there were still pockets of snow left on the ground in sheltered areas. Evapotranspiration for the month was 27.8 millimetres, the highest since October 2012.

The easterly winds throughout most of the month were bitingly cold, and at times gale force. The average wind speed for the month was 4.9 mph and the average gust speed was 7.8 mph, both March records. The maximum wind speed was 20.7 mph from 113° (ESE) on the 25th at 11:39, and the maximum gust speed was 34.5 mph from 113° (ESE), two minutes earlier at 11:37. The total windrun for the month was 3586 miles, the highest of 2013 so far.

The average barometric pressure for the month was 1009.6 millibars, with the highest being 1031.1 millibars on the 1st at 11:40, and the lowest being 987.5 millibars on the 17th at 16:35.

Weather chart for March 2013.

Weather chart for March 2013.


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