Author: Eric Gilbert

FEBRUARY 2013
February is invariably the harshest winter month and proved so in 2013 with a mean 1C lower that January 2013 and over 2C lower than December 2012. It was the coldest February since 1996 with a mean 1.8C below the long-term average. There were only nine days with a maximum above the average although the most severe air frost, which occurred on the 19th, produced a low of -4.8C which is mild compared to the extreme low of -13.8C that was recorded in February 2012. An air frost occurred on sixteen days, five above the average.
The total rainfall was 44.3mm, which is 70% of the long-term average and the first below average month since September 2012.
The last week was notable for strong northeasterly winds circulating around an anticyclone centred over Scandinavia producing low temperatures that combined to produce a wind chill of -5C on two days.
Snow fell on four days with morning fog seen on three days although there were several misty days with low cloud.
WINTER 2012
The mean was 0.7C below the long-term average with an air frost occurring on 41 days, which is seven above the long-term average.
The rainfall total was 331mm that is 138% of the long-term average or +92mm. It was the fourth wettest winter since my records began 30 Years ago.

The first ten days of January were mild and mainly dry, not at all wintry. However, on the 12th a change to cold continental air brought us back to winter with the first light snowflakes falling in the afternoon. Temperatures dropped over succeeding days with thirteen consecutive days of air frost and snow falling on six days with the main accumulations of 13cm and 4cm. The cold days, combining with winds from an easterly quarter, gave a wind chill as low as -7c on the 19th and 20th. The mean temperature was 0.6C below the long-term average with the lowest temperature on the 25th when the thermometer dropped to -5.4C. With winds changing into a southerly direction at the end of the month temperatures recovered and a maximum of 12.6C was noted on the 29th, the warmest January day since 2002. During this latter period strong winds set in with gusts exceeding 30mph over the last five days and a maximum gust, during a rain squall on the 27th, giving a maximum of 42mph.
Rainfall and melted snow gave a total precipitation of 87.8mm, almost equal to the long-term average.
With so much cloud cover it is not surprising that solar power was down almost 10% on the total for 2012 and with ten hours less sunshine.

DECEMBER
December continued the pattern of disturbed weather with just eight dry days toward the beginning of the month but very wet days during the latter half. It was the wettest December I have recorded with a total of 155.1mm, which is 175% of the long-term average (+67mm). There were five days with totals in double figures, the highest being 28.0mm on the 19th. Due to the predominantly overcast conditions the mean temperature was 0.3C above the long-term average. There were 11 days with air frost, the most severe occurring on the 12th when the thermometer dropped to -6.3C. The last four days of the month were very windy with gusts exceeding 30mph every day.

YEAR 2012
Rainfall: This was the most memorable feature of 2012 with the wettest spring, summer and autumn seasons on record. After a very dry start to the year there were 7 months when the monthly average was greatly exceeded. It was the second wettest year after 2002 (1146mm) with a total of 1112mm, which is 135% of the long-term average and +279mm. The wet and overcast conditions were brought about by frequent depressions crossing the country and record low pressures were noted for April, September and December. September 23rd brought the wettest day with a total of 31.7mm. The number of dry days, at 133, was the second lowest after 131 in 1998. There was a record of 45 days with daily totals exceeding 10mm, previously held in 2000 with 41.
Temperature: There were seven months when the mean temperature was below the long-term average. A record minimum for February was recorded on the 11th when the thermometer dropped to -13.8C. There were only brief glimpses of real summer weather such as the third week in August when it was dry for several days, maxima reached into the high twenties and a maximum of 29.4C was noted during August 25th. The total number of air frosts, at 64, was close to the average of 61 since 1984.
Diurnal Temperatures: It is interesting to note that the trend for the daily range of temperatures in December has increased by approximately 4C since the 1980.
Unusual Occurrence: A wind funnel was observed for the first time at this station on 5th July, to the north of Marlborough, lasting for over 10 minutes.

NOVEMBER 2012
With depressed temperatures and heavy rainfall, November was a disappointing end to autumn. The mean temperature was 0.9C below the long-term average with air frosts on nine days, the minimum being -3.4C on the 31st; this preceded the coldest day when the thermometer struggled to each 3.8C.
Rainfall was a major feature of the month totalling 128.4mm, which is 144% of the long-term average of 89.5mm. This is not a record as the greatest rainfall for November was set in 2002 with 203.5mm. There were five days when rainfall exceeded double figures, the heaviest being 22.9mm and 25.4mm on the 20th and 24th respectively.
AUTUMN 2012
The mean temperature was 9.4C being 0.9C below the long-term average. It was the fourth coldest since my records began in 1984 but well above the record low of 7.95C in 1993.
It was the wettest autumn since 2006 with a total of 309mm, 130% of the long-term average and the sixth wettest since 1984. The record was set in 2006 with 401mm.
SUMMER & AUTUMN 2012
The total rainfall for this six-month period of June to November was a record of 637.2mm, some 153% (221mm) of the long-term average. This supersedes the previous record of 558.6mm set in 1993 and contrasts with the lowest of 243.1mm set in 1990.

The statistics for October show another cool and wet month. The mean temperature was 1.1C below the long-term average, the coldest since 2008, with the lowest mean maximum temperature since 1993 at -1.4C. It was the fifth coldest October since 1984. The warmest day was the 1st with a lowly maximum of just 16.8C and only seven days struggled above the mean for the month. The first air frosts of the autumn occurred on three mornings with the lowest temperature on the 14th at -1.7C.
A total of 121mm of precipitation was recorded being 141% of the long-term average and the wettest October since 2006. The long-term average is 88mm but since 1984 seven years have produced totals above 120mm with the record set in 2004 which had a total of 159mm. There were three days with significant rainfall totals namely 20.1mm, 18.1mm and 16.6mm on the 17th, 31st and 5th respectively. Not surprisingly there were only six totally dry days.
The solar energy, due to the many overcast days, was just 87% of the last few years.
There were six days with morning fog but several others when low cloud persisted producing misty conditions.