December 2014: Sunny, dryer than average

This December was the sunniest on record in my series going back to 1877. Over 90 hours of sunshine was recorded in this area which is 224% of what we can expect to see during an average December.

It was the sunniest December on record in the series going back to 1979. Some 11 mornings were completely clear at the 9am observation time

It was the sunniest December on record in the series going back to 1979. Some 11 mornings were completely clear at the 9am observation time

Mean temperature for the month was precisely average at 5.6C. Rainfall of 39.9mm was 75% of average – the driest since 2010.

The month was 0.7C cooler than last December – with just under half the rain that fell in that wet and stormy month.

The first day of December was cloudy, dull and dreary with drizzle in a keen east wind. The following days alternated between rain and sun and some night frost. On the 6th the day started sunny with just a few cirrus clouds – overnight frost persisted all day in my garden with a grass min at -2C. The 9th began sunny after a hard frost but then the temperature climbed for 19 hours with cloud building and brief rain at 2am before the cold front passed.

The wettest day occurred on the 11th. The day started sunny but blustery showers blown in on strong WSW winds coupled together with 6 hours of rain overnight produced 11.5mm.
Things turned much milder in the 3rd week with frequent, chiefly light rain, abundant sunshine and an absence of frost. On the 18th the temperature reached 14C.

Christmas Eve saw the weather begin to cool down again with progressively colder nights. Boxing Day was a cloudy, cold day with rain spreading in during the evening and a notable warm sector raising the temperature to nearly 9C at midnight. The first lowland snow of the winter was reported up north. The month ended with long sunny days and sharp frosts, a couple persisting through the day.

Air frosts: 12

Ground frosts: 15

This satellite picture taken on December 27th, 2014, shows the LP clearing through to leave us in clear, deep cold air

This satellite picture taken on December 27th, 2014, shows the LP clearing through to leave us in clear, deep cold air

From this month, using a similar method for predicting winter, I am going to finish these monthly reviews with a look ahead to see what next month has in store.

The general consensus of the models suggest the first half of the month is going to be mostly unsettled with a mixture of wind and rain off the Atlantic and transient ridges from the south bringing mild, sunny days.

Looking at the 10-day ahead forecast on Netweather suggests the temperature will be just above average with rainfall also slightly higher than normal.

Beyond that, for anyone seeking any snowy weather, the outlook is uncertain. Using a similar method to my Christmas forecast, which was correct at 25 days ahead, I’ve had a look back in the archives to see if there is any precedent in the pattern we’ve had this December.

The simple answer is there is no over-riding signal for any weather type, save that there appears no chance of a repeat of the very mild January of last year. Taking all the probabilities together gives an 88% chance that January will be average to cold – so perhaps there will be some snow in the second half of the month.

january probabilities

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4 responses to “December 2014: Sunny, dryer than average

  1. Pingback: Winter 2014/15 – second sunniest on record | Wanstead Meteo·

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