PITSFORD HALL WEATHER STATION NORTHAMPTON, UNITED KINGDOM MONTHLY WEATHER REPORT - AUGUST 2002 Headline: Unsettled start with heavy outbreaks of rain. A ridge of high pressure gave a settled spell around mid-month and at the end with further showers in between. Generally warmer than average. The first 10 days of August were generally unsettled. Low pressure dominated the scene and there were frequent outbreaks of rain, occasionally heavy. 9.6mm fell in the space of 1 hour on the 7th at Pitsford Hall during a thunderstorm. Similar storms in other parts of the Midlands on the same day produced localised flooding, but there were no reports of problems within the county. Further particularly wet days were recorded on the 8th (8.2mm) and the 10th. A fairly quiet period followed until the 18th. The low pressure system have finally moved away by the 12th and a ridge of high pressure began to extend across the region from the Azores. It remained dry and some reasonably sunny days were recorded (9.4hrs on the 14th and 10.7hrs on the 15th). It became noticeably warmer from the 14th onwards with daytime maxima typically in the high 20s, reaching 30.8C on 17th. The very warm spell triggered some thundery showers, but none were recorded at Pitsford Hall until the 19th when 4.7mm fell in 1 hour. An unsettled spell then followed with low pressure remaining over the North Sea. Thundery showers broke out on the 24th and overall temperatures fell consistently. Mornings were plagued by mist and patchy fog as winds swung round to a north or north-westerly direction. The month ended with a ridge of high pressure from the Azores once again becoming established across the county. Despite a fairly cool start, temperatures soon recovered and it remained dry apart from a slight shower on the 30th as an area of low pressure tracked eastwards across northern England. Climatological & Agromet Statistics - August 2002 Air Temperatures The Highest Maximum: 30.8C on 17th The Lowest Maximum: 16.6C on 26th The Highest Minimum: 16.7C on 1st The Lowest Minimum: 8.5C on 26th The Mean Maximum: 22.3C The Mean Minimum: 12.9C The Overall Mean: 17.6C Difference from the Monthly Mean: 1.3C Relative Humidity: Highest Relative Humidity (at 0900): 97.8% on 28th Lowest Relative Humidity (at 0900): 57.3% on 2nd Mean Relative Humidity (at 0900): 80.7% Dew Point: The Highest Dew Point (at 0900): 16.8C on 19th The Lowest Dew Point (at 0900): 9.6C on 31st The Mean Dew Point (at 0900): 14.1C Rainfall: Total: 33.9mm Difference from the Monthly Mean: 69.6% Duration: 20.6hrs Highest 24 hour fall (from 0900): 9.6mm on 7th Rain Days (>/=0.2mm): 11 Wet Days (>/=1.0mm): 8 Sunshine: Total Duration of Bright Sunshine: 138.0hrs Sunniest day: 10.7hrs on 15th Cloud cover (mean at 0900): 5.9 oktas Sunless days: 2 Pressure (reduced to sea level at 0900): The Highest Pressure: 1025.1mb on 26th The Lowest Pressure: 1002.4mb on 9th Mean Pressure (recorded at 0900): 1015.6mb Winds Run of wind (mean over 24 hrs): 73.0miles Mean daily wind speed: 4.0mph Run of wind (to date): 2261.7miles Highest Maximum Gust: 26mph on 11th Highest wind strength (at 0900): 17.3mph on 12th Mean wind strength (at 0900): 6.3 mph Winds from the Following Directions: North 6 North-north-east 3 North-east 2 East-north-east 0 East 0 East-south-east 0 South-east 2 South-south-east 1 South 0 South-south-west 5 South-west 0 West-south-west 2 West 0 West-north-west 0 North-west 2 North-north-west 8 Calm 0 Ground Temperatures: Lowest Grass Minimum: 5.9C on 26th Mean Grass Minimum: 11.0C Lowest Concrete Minimum: 7.6C on 26th Mean Concrete Minimum: 12.3C Lowest Bare Earth Minimum: 8.5C on 26th Mean Bare Earth Minimum: 13.4C Soil/Earth Temperatures: Surface mean: 19.5C 5cm mean: 17.5C 10cm mean: 17.9C 20cm mean: 18.0C 30cm mean: 18.5C 40cm mean: 18.4C 50cm mean: 18.6C 100cm mean: 17.4C Days with: Thunder: 2 Hail less than 0.5cm: 0 Hail greater than/equal to 0.5cm: 0 Snow or snow & rain: 0 Snow lying: 0 Fog: 0 Air Frost: 0 Duration of Air Frost: 0 Ground Frost: 0 Total Evaporation (tank): 83.09mm