Weather Statistics for January 2006

Headline: Generally a very dry month well below average. Mild during the third week before ending with a cold snap.

January started on a rather changeable theme with spells of rain and on the whole it was rather cloudy. Daytime maxima were slightly above average for the time of year and overnight we were free of any air frost, although a slight ground frost was recorded on most nights.

From the 5th a ridge of high pressure extended across to the British Isles from Scandinavia surpressing any significant rain, although some granular snow was reported at 0900hrs. The high brought with it a fair amount of cloud and hardly any sunshine was recorded until the 11th. Daytime temperatures fell quite dramatically with highs struggling to reach 3C falling close to freezing overnight, the cloud preventing temperatures falling too severely. It was cold enough on the 7th for a moderate fall of snow, although there was no accumulation to report at 0900hrs. Rain fell on the 8th associated with the progression of an occluded front to the south and the start of a period of more unsettled weather.

A deep low had developed between Scotland and Iceland by the 10th and this introduced some strong winds across the county gusting to 40mph at Pitsford on the 10th. Frontal systems also fed through producing spells of rain, although amounts were slight (1.5mm) in comparison to areas further north and west. Some sunshine followed the rain on the 11th, the first significantly sunny day of the month and temperatures during the afternoon climbed to 12.8C.

For a few days at least until the 15th the county came under the influence of high pressure centred over mainland Europe. Although rather cloudy at times, it was essentially dry apart from the 14th which saw a frontal system slow down as it encountered high pressure towards the south-eastern corner of the UK. Daytime temperatures generally held up at around 7 or 8C with winds coming in from a general southerly direction.

Once a couple of active frontal systems had worked eastwards on the 16th delivering a fair amount of rain a fairly vigorous south-westerly flow introduced a mild spell of weather with maxima on most days following the 17th exceeding 10C, several degrees above the mid-January norm with little frost worries overnight, although a ground frost on the 18th was triggered by a brief change to a more northerly flow.

From the 20th onwards high pressure became dominant over the UK from the south-west. This introduced some decent sunshine on both the 20th and 21st, although as the wind dropped it became increasingly cloudy and correspondingly temperatures fell quite markedly with highs reaching just 1.7C on the 24th followed by a hard and penetrating frost on the morning of the 25th (-3.8C). The switch to a north or north-easterly airstream maintained the cold spell until the end of the month and, although a few sunny days were enjoyed, by the 30th the high was beginning to introduce a spell of anticyclonic gloom that would last into February.

Overall, this was the driest January in Northampton since 2000 (13.5mm) and the third driest since 1880 (8.4mm) when records began.


Air Temperatures    
The Highest Maximum:   12.8 C on 11th
The Lowest Maximum:    1.7 C on 24th
The Highest Minimum:   6.0 C on 11th
The Lowest Minimum:    -3.8 C on 25th
The Mean Maximum:    6.5 C  
The Mean Minimum:    1.7 C  
The Overall Mean:    4.1 C  
Difference from the Monthly Mean:  -0.3 C  
    
Relative Humidity:    
Highest Relative Humidity (at obs):  100.0 % on 7th & 22nd
Lowest Relative Humidity (at obs):  73.6 % on 25th
Mean Relative Humidity (at obs): 92.9 %  
    
Dew Point:    
The Highest Dew Point (at obs):  8.9 C on 19th
The Lowest Dew Point (at obs):   -3.1 C on 24th
The Mean Dew Point (at obs):   3.0 C  
    
Rainfall:    
Total:      17.7 mm  
Difference from the Monthly Mean:  33.8 %  
Duration:     23.3 hrs  
Highest 24 hour fall (obs to obs):  5.1 mm on 16th
Rain Days (>/=0.2mm):    13   
Wet Days (>/=1.0mm):   7   
    
Sunshine:    
Total Duration of Bright Sunshine:  39.9 hrs  
Sunniest day:     6.3 hrs on 26th
Days without sunshine:	15
Cloud cover (mean at obs):   7.0 oktas  (87.5%)
     
Pressure (reduced to sea level):    
The Highest Pressure:    1037.9 mb on 22nd
The Lowest Pressure:    1000.6 mb on 1st
Mean Pressure (recorded at obs):  1023.3 mb  
    
Winds    
Run of wind (mean over 24 hrs):  120.0 miles  
Mean daily wind speed:    6.5 mph 
Highest mean daily wind speed:  18.5 mph on 11th
Run of wind:     3721.4 miles  
Highest Maximum Gust:   40 mph on 10th
Highest wind strength (at obs):   18.4 mph on 10th
Mean wind strength (at obs):   6.9 mph  
    
Winds from the Following Directions:    

N 8 NE 2 E 4 SE 2 S 5 SW 3 W 1 NW 4 Calm 2
    
Ground Temperatures:     
Lowest Grass Minimum:   -8.5 C on 25th
Mean Grass Minimum:    -1.9 C  
Lowest Concrete Minimum:   -4.0 C on 25th
Mean Concrete Minimum:   1.3 C  
Lowest Bare Earth Minimum:   -2.5 C on 28th
Mean Bare Earth Minimum:   1.6 C  
    
Soil/Earth Temperatures:     
Surface mean:     3.4 C  
5cm mean:     3.4 C  
10cm mean:     3.7 C  
20cm mean:     4.2 C  
30cm mean:     4.3 C  
40cm mean:     4.4 C  
50cm mean:     4.9 C  
100cm mean:     5.5 C  
    
    
Days with:    
Thunder:     0   
Hail less than 0.5mm:    0   
Hail greater than/equal to 0.5mm:  0   
Snow or snow & rain:    2   
Snow lying:    0
Fog      4
Air Frost:    8
Duration of Air Frost:   25.0hrs
Ground Frost:    22   
   
Total Evaporation (tank)   12.14 mm

    
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 Januarysubscribe to this report at a rate of £15 per year. Please contact the station for further information.