Monthly Weather Review - Pitsford Hall

Headline: Generally cold with temperatures significantly below average. Dry with above average sunshine.

For the first two weeks the weather across Northamptonshire was dominated by a predominantly north-westerly airstream and a number of depressions which tracked south-eastwards. Temperatures were generally depressed, although good spells of sunshine by day were followed overnight by clear skies and frequent frosts. Snow fell across the county on the 2nd and whilst a vigorous depression brought blizzard conditions across a large part of the UK on the 4th the county experienced torrential rain and strong winds during the morning – gusts up to 40mph were recorded at Pitsford and some areas received more than 10mm of rain in the space of 6 hours. However, most of the county was bathed in sunshine by lunchtime. Another active low tracked across the UK between the 12th and 14th introducing another spell of particularly wet weather across the county. It also became windy again with gusts on the 12th reaching 39mph. There was a slight fall of granular snow before the rain arrived on the 12th.

From the 16th the wind changed direction and a west or southwesterly airstream developed. Consequently, conditions became milder and by the 20th daytime temperatures had reached 12.5C, significantly above the norm for mid December. In fact overnight temperatures leading into the 22nd only fell to around 9.0C - still more than would be expected by day. There were occasional outbreaks of rain, but amounts were largely insignificant apart from the 19th when an active system brought 4.6mm of rain at Pitsford accompanied by strong winds. By contrast areas further north and west were generally very wet.

By the 24th the UK began to feel the effects of an area of high pressure which had been extending northwards from

Iberia

. The cloud brought in by weak frontal systems on the preceding few days became trapped beneath this high resulting in a rather gloomy run-up to Christmas. With the cloud and the transfer of wind direction to the south-east bringing in colder air from central Europe, temperatures began to fall. However, overnight temperatures were checked by this blanket of cloud only falling a few degrees below daytime values. The high transferred to Scandinavia on Christmas Day where it remained fairly stationary until the end of the month introducing a cold easterly airstream. Whilst Christmas Day itself remained rather grey, some good spells of sunshine were recorded on subsequent days and with the clearer skies came the inevitable frosts overnight. As the month came to a close it became bitterly cold. Temperatures on New Year’s Eve never rose above freezing at Pitsford and as they struggled to climb from a low of -4.1C the last day of 2008 was the coldest of the entire year.

With a mean temperature of just 3.7C this was the coldest December in Northampton since 2001 (3.1C). With around half the expected rainfall (31.8mm) it was also the driest December since 2004 (19.6mm) and the second driest since 2001 (16.5mm). Sunshine totals were also above average, although at Pitsford we did not record the record breaking December sunshine that was recorded as an average for the UK. Nevertheless, we still recorded more sunshine in December than in November.

Air Temperatures    
The Highest Maximum:    12.5 C on 20th
The Lowest Maximum:    -0.1 C on 31st
The Highest Minimum:    9.0 C on 22nd
The Lowest Minimum:    -4.1 C on 31st
The Mean Maximum:    6.1 C  
The Mean Minimum:    1.2 C  
The Overall Mean:    3.7 C  
Difference from the Monthly Mean:  -0.8 C  
    
Black Bulb    
Maximum (at 0900):    10.2 C on 20th
Mean (at 0900):    3.1 C  
    
Relative Humidity:    
Highest Relative Humidity (at 0900):  100.0 % on 9th,12th,14th,16th,31st.
Lowest Relative Humidity (at 0900):  81.7 % on 21st
Mean Relative Humidity (at 0900):  93.3 %  
    
Dew Point:    
The Highest Dew Point (0900):   10.2 C on 20th
The Lowest Dew Point (at 0900):  -1.9 C on 30th
The Mean Dew Point (at 0900):   2.2 C  
    
Rainfall:    
Total:      31.8 mm  
Percentage of the Monthly Mean:  50.6 %  
Duration:     41.3 hrs  
Highest 24 hour fall (0900 to 0900):  9.7 mm on 13th
Rain Days (>/=0.2mm):    11   
Wet Days (>/=1.0mm):    5   
    

Sunshine:    
Total Duration of Bright Sunshine:  48.8 hrs  
Sunniest day:     4.9 hrs on 30th
No. of days without sunshine:   10   
Percentage of the Monthly Mean:  126.1 %  
Cloud cover (mean at 0900):   5.9 oktas (73.8 %)
    
Pressure (reduced to sea level at 0900):    
The Highest Pressure:    1039.7 mb on 26th
The Lowest Pressure:    977.3 mb on 4th
Mean Pressure:     1018.6 mb  
    
Winds    
Run of wind (mean over 24 hrs):  126.2 miles  
Mean daily wind speed:    6.8 mph  
Run of wind (cumulative):   3913.3 miles  
Highest Maximum Gust:   40 mph on 3rd
No. of gusts of 50mph or more:   0   
Highest wind strength (at 0900):  21.9 mph on 4th
Mean wind strength (at 0900):   8.3 mph  
    
Winds from the Following Directions:    

N 1 NE 3 E 4 SE 1 S 5 SW 6 W 2 NW 7 Calm 2
    
Concrete     
Lowest Concrete Minimum:   -6.6 C on 31st
Mean Concrete Minimum:   -0.7 C  
    
Evaporation    
Piche      26.2 ml  
Pan      4.96 mm      

Days with:    
Thunder:     0   
Hail <5mm:    0   
Hail >/=5mm:     0   
Snow or snow & rain:    2   
Snow lying:     0   
Fog:      1   
Air Frost:     14   
Duration of Air Frost:   57.0hrs
Gales:      0   



All data © Pitsford Hall weather station.

The weather station publishes a full Monthly Weather Report (ISSN 1741-4733) which is distributed to libraries across Northamptonshire. This report comprises a full UK weather diary, reports of extreme weather events across the county, statistics from Pitsford Hall's affiliated stations across the county as well as news from the weather station itself. Individuals may download this report for £2 or take out an annual subscription for the paper-based report for £25. Click here for further details.