Monthly Weather Review - Pitsford Hall

Headline: Very dry, unseasonably warm and sunny. The driest April locally since 1938.

April opened as an area of high pressure developing south of Iceland extended south-eastwards across the

. This high was to become a fairly stationary feature across the British Isles right through the first week until the 8th. Winds were generally brisk at first and from the north-east, but generally eased over the next few days. Both the 1st and the 2nd saw some decent sunshine for early April, although the remnants of a weak weather front worked southwards mainly along the east coast on the 3rd and 4th and introduced a fair amount of cloud across the county with a small amount of trace rainfall recorded at Pitsford. The weather front introduced some colder air behind with some chilly nights and ground frosts between the 4th and the 8th.

By the 9th the high had started to retreat from the UK towards the south-west. This resulted in winds swinging round from the north-west and, although a frontal system had managed to make in-roads across northern England, its impact on the county was negligible and, other than a fairly cloudy day on the 10th, we continued to enjoy some good sunshine and temperatures rose gradually with daytime highs in the mid to high teens. The high quickly regained control across much of the UK and over the next few days moved steadily across England and Wales towards the North Sea.

The fairly protracted period of dry weather began have a visible effect on some of the climate observations at Pitsford on the 11th with the first report of ground as being very dry with the appearance of significant cracking. Although the high tended to remain centred over southern Scandinavia over the next few days, its influence continued to extend across the UK towards Northamptonshire. By the 14th, warm air was being drawn in slowly across the UK from mainland Europe and daytime highs for the first time in 2007 exceeded 20C at Pitsford. The following afternoon temperatures had reached 23.4C, the warmest April day since 2003.

A cold front did work southwards across the UK on the 16th, but it would have little impact on the UK as it came up against a new area of high pressure building up from the south-west. The only real observation across the county was one of increased cloud and cooler temperatures. However, over the next few days the high would position itself centrally across the UK maintaining settled weather with some fine sunny days.

By the 21st, the high had migrated towards Denmark to allow the first run of significant weather systems in from the west. However, with high pressure pretty much still in charge across much of UK, these systems were to make little progress towards the south-east. Small amounts of rain were recorded at Pitsford on the 22nd and again on the 23rd, but it would not be until the 26th that the county would see any significant rain and then only a total of 1.2mm.

The month would come to an end with high pressure still in charge across the UK, centred at first over Scotland and then drifting slowly across the North Sea.

Overall this was the warmest April in Northampton since 1997 (12.8C) and the driest April in Northampton since 1938 (1.0mm).

Air Temperatures    
The Highest Maximum:   23.4C on 15th
The Lowest Maximum:   8.5C on 3rd
The Highest Minimum:   13.1C on 25th
The Lowest Minimum:   2.3C on 4th
The Mean Maximum:   17.1C  
The Mean Minimum:   6.1C  
The Overall Mean:   11.6C  
Difference from the Monthly Mean: +2.5C  
    
Relative Humidity:    
Highest Relative Humidity (at 0900): 100.0% on 13th
Lowest Relative Humidity (at 0900): 59.7% on 19th
Mean Relative Humidity (at 0900): 77.2%  
    
Dew Point:    
The Highest Dew Point (0900):  13.1C on 24th
The Lowest Dew Point (at 0900): 3.3C on 4th
The Mean Dew Point (at 0900):  7.4C  
    
Rainfall:    
Total:     1.6mm  
Difference from the Monthly Mean: 3.0%  
Duration:    3.0hrs  
Highest 24 hour fall (0900 to 0900): 1.2mm on 26th
Rain Days (>/=0.2mm):   2   
Wet Days (>/=1.0mm):   1   
    
Sunshine:    
Total Duration of Bright Sunshine: 213.3hrs  
Sunniest day:    11.9hrs on 28th
No. of days without sunshine:  1   
Difference from the Monthly Mean: 159.4%  
Cloud cover (mean at 0900):  4.4oktas  (55%)
    
Pressure (reduced to sea level):    
The Highest Pressure:   1035.5mb on 2nd
The Lowest Pressure:   1012.0mb on 25th
Mean Pressure (recorded at 0900): 1023.7mb  
    
Winds    
Run of wind (mean over 24 hrs): 104.7miles  
Mean daily wind speed:   5.7mph  
Run of wind (cumulative):  3140.3miles  
Highest Maximum Gust:   34mph on 1st
No. of gusts of 50mph or more:  0   
Highest wind strength (at 0900): 19.6mph on 1st
Mean wind strength (at 0900):  7.8mph  
    
Winds from the Following Directions:    

N 8 NE 7 E 0 SE 3 S 4 SW 1 W 2 NW 4 Calm 0  
    
Ground Temperatures:     
Lowest Grass Minimum:   -3.0C on 4th
Mean Grass Minimum:   2.4C  
Lowest Concrete Minimum:  0.4C on 5th
Mean Concrete Minimum:  5.3C  
Lowest Bare Earth Minimum:  1.0C on 4th
Mean Bare Earth Minimum:  5.3C  
    
Soil/Earth Temperatures:     
Surface mean:    11.0 C  
5cm mean:    10.2 C  
10cm mean:    10.5 C  
20cm mean:    11.0 C  
30cm mean:    11.2 C  
40cm mean:    10.9 C  
50cm mean:    11.0 C  
100cm mean:    9.6 C  
    
Days with:    
Thunder:    0   
Hail <5mm:    0   
Hail >/=5mm:    0   
Snow or snow & rain:   0   
Fog:     1   
Air Frost:    0   
Ground Frost:    5   
Gales:     0   
    
Total (Pan) Evaporation:  86.13 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 may download this report for £2 or take out an annual subscription for the paper-based report for £25. Click here for further details.