February 2017 summary

February was a mild and breezy month, with rainfall about average.

The month started with a procession of Atlantic lows, including a deep one which passed across northern France on the 3rd. There were wind warnings for the UK, but in the event all we saw was some heavy rain and gusty winds during the early evening – nothing out of the ordinary for February. The 5th and 6th brought the first two frosts of the month, but only just with the thermometer less than a degree below zero.

A ridge from the Azores high brought a quiet spell on the 8th with clear skies, and another air frost early on the 9th produced the lowest temperature of the month at -1.6C – quite modest for February. This was also the last air frost of the month – there were only three, and we might expect double that number in February.

The ridge soon receded, to be replaced on the 10th with high pressure over Scandinavia. This meant that some low pressure system passed south of us, initially resulting in a gentle but very cold and dry easterly breeze. The high pressure moved slowly south-west, and as it did so it drew warmer air up from the south: by the 18th daytime temperatures were into double figures.

On the 19th the high pressure moved off east and for the rest of February it was back to the Atlantic lows, including Doris on the 23rd – this system brought our highest wind speeds of the month (30kts gusting to 43kts), but it was the north of the UK which was most affected. The month ended with a good deal of unsettled weather, with hail and sleet on the 27th.

The average temperature for February was 6.8C, about a degree above normal thanks to that warm spell in the middle of the month, and total rainfall was about average at 57.6mm.

Today is the first day of meteorological spring, and the average temperature for winter 2016/17 was 6.1C, and the rainfall total was 139.8mm – both figures close to normal.

Farewell to Doris

The winds are easing a bit now (though it probably doesn’t feel like it if you are outside) as Storm Doris moves off into the North Sea, so time for a quick update. Doris has moved quickly across the north of the UK, from Northern Ireland at 0400 to the Yorkshire coast at 12 noon. The cold front arrived here at about 0625 and brought 1.8mm of rain, following which the westerly wind grew in strength to peak about mid-morning. The maximum average wind speed was 27.8kts at 1048, and the strongest gust was 43kts at 0957. That’s lively, but wind is often a feature in February and neither of these figures is a record-breaker here. Doris was always going to affect the north of the UK much more than us soft southerners. Hope you haven’t seen too much damage wherever you are.

January 2017 summary

2017 got off to a dull and wet start on the 1st as a cold front passed by, with the following cold air adding to the gloom in the afternoon. It didn’t last, though, because the next few days were dominated by a high pressure system and we saw clear skies and overnight frosts. This high pressure system stayed with us until the 7th, when it moved off east and allowed the lows stacked up in the Atlantic to cross the UK bringing milder air and a little rain. A low pressure system in the North Sea threatened a tidal surge on the 13th, but the defences held and no harm was done.

High pressure from the west took over again on the 14th, moved across the south of the UK and settled over Europe by the 17th, with us on the boundary between cold continental air and the warm Atlantic flow. The result was calm weather, but to begin with it was dull, misty and damp – it wasn’t until the evening of the 18th that the drier continental air reached us, with clear skies and more overnight frosts. The lowest temperature was -4.7C early on the 21st, and by now January was looking likely to be a particularly dry month with below-average temperatures.

The continental high moved away on the 27th, allowing warm Atlantic air back in and causing temperature to rise sharply. The 28th produced some heavy convective showers with magnificent cloud formations in otherwise clear skies. By the end of the month temperatures were well into double figures, and persistent rain brought totals a bit closer to normal.

There was no snow, no exceptional winds and, thanks to that warm, wet end to the month January’s average temperature was only slightly below normal at 5.0C. Rainfall was 56.8mm, making this our third-driest January.

December 2016 summary

December was notable for persistent high pressure – the barometer never dropped below 1013.8hPa, which means that the pressure remained above the global average (1013hPa) throughout the month. We recorded our highest December average pressure of 1026.4hPa, and a new record high pressure reading of 1044.3hPa was reached on the 27th.

High pressure often brings calm and dry weather and blue skies, but in winter it may also mean persistent cloud and fog instead of sunshine. All of those features were present during December. Rainfall was 25.4mm, well under half the average and the lowest December total we have recorded; and the wind run came to 889nm which is about one third of our December average, making this our quietest December on record. While we’re talking about records, we also saw our highest December temperature of 15.6C on the 7th December, and our warmest Christmas day (0600-1800) with an average of 12.8C.

That’s an impressive list of new records for one month, but all the other features associated with winter high pressure were present too, even if they aren’t so easily measured. We had clear skies, gloomy days and a fair helping of fog. There were no gales but plenty of calm spells, and there was little in the way of rain with the total on the wettest day (the 15th) only amounting to 8.2mm.

December got off to a cold start, with the thermometer down to -4.9C early on the 1st. There was high pressure across the UK, and fog which formed overnight never cleared during the day: as a consequence the temperature remained below freezing all day, the first time that has happened here since 2010.

We remained under the influence of high pressure, either over the UK or not far away, for almost the whole month – Atlantic lows only made their presence felt from the 12th to the 15th and again around the 21st, and even then we were only on the edge of lows passing to our north. Scotland wasn’t so lucky, with rain and gales there while it was calm here.

Some figures for 2016:-

  • Rainfall total was 606.6mm, a little below average but nothing exceptional
  • The mean temperature for the year was 11.1C, close to normal
  • The highest temperature was 32.4C in July, a new record for this station, and the lowest was an unremarkable -5.9C in January.
  • February saw new records set for wind speed.

That’s a lot of new records for one year, and quite a few of those in December – 2016 will be a hard act to follow.

This is a record-breaking high pressure system

The southern half of the UK is sitting under an intense high pressure system which brought clear skies overnight and an air frost this morning, with a minimum temperature of -1.4C.

Nothing too remarkable there, you might think, but this morning we have recorded an atmospheric pressure of 1044.0 hPa. That’s a new record for this station – the previous high was 1043.9 hPa on 8 February 2012 – and the trend is still upwards (just).

This system won’t hang around for long, unfortunately, so enjoy the cold, fine weather while you can. Quite a contrast to the balmy temperatures we had on Christmas Day!