PITSFORD HALL WEATHER STATION NORTHAMPTON, UNITED KINGDOM MONTHLY WEATHER REPORT AUGUST 2000 Despite the mean temperature being above the long-term average, this August was a much maligned month. The weather was distinctly changeable with some wet spells alternating with periods of fine sunny days. The month began with low pressure in charge. Although the county escaped much of the rain, some notable thundery downpours were recorded on the 3rd. At Pitsford Hall 6.7mm fell in just 15 minutes just after 1600hrs GMT. High pressure then built from the 4th bringing a spell of warm weather with daytime maxima generally above 22C. It remained dry apart from some showers on the 7th. An unsettled spell then marked the mid-month period with some frequent outbreaks of rain including 9.1mm on the 15th and 10.1mm on the 18th. Temperatures then deteriorated from the maximum of 27.4C on the 12th. Despite the rain, some good sunshine was recorded on several days. The weather was influenced by high pressure during the third week bringing about a gradual recovery in temperatures and daily sunshine. However, a short unsettled spell then followed on the 25th and 26th with outbreaks of rain before high pressure re-introduced a fine spell towards the end of the month. As if only to emphasise its fickle nature, August went out with some heavy rain on the 31st. Air Temperatures The Highest Maximum: 27.4C on 12th The Lowest Maximum: 17.1C on 18th The Highest Minimum: 16.4C on 10th The Lowest Minimum: 8.6C on 29th The Mean Maximum: 22.2C The Mean Minimum: 12.3C The Overall Mean: 17.3C Difference from the Monthly Mean: 0.7C Relative Humidity: Highest Relative Humidity (at 0900): 98.9 % on 29th Lowest Relative Humidity (at 0900): 61.9 % on 25th Mean Relative Humidity (at 0900): 82.8 % Dew Point: The Highest Dew Point (at 0900): 17.7C on 14th The Lowest Dew Point (at 0900): 11.7C on 31st The Mean Dew Point (at 0900): 13.8C Rainfall: Total: 48.6mm Difference from the Monthly Mean: 88.4% Duration: 30.6 hrs Highest 24 hour fall (from 0900): 10.1mm on 18th Rain Days (>/=0.2mm): 11 Wet Days (>/=1.0mm): 10 Lowest pH: 5.91 on 18th Sunshine: Total Duration of Bright Sunshine: 223.3 hrs Sunniest day: 12 hrs on 12th Sunless days: 1 Cloud cover (mean at 0900): 4.9oktas or 61.3% Pressure (reduced to sea level): The Highest Pressure: 1025.7 mb on 7th & 23rd The Lowest Pressure: 1000.6 mb on 1st Mean Pressure (recorded at 0900): 1017.9mb Winds Run of wind (mean over 24 hrs): 66.7miles Mean 24 hr wind speed: 3.6 mph Highest 24 hr wind speed: 7.2mph on 6th Run of wind: 2068.3 miles Highest Maximum Gust: 26 mph on 25th Highest wind strength (at 0900): 15mph on 1st Mean wind strength (at 0900): 7.3 mph Winds from the Following Directions: N 5, NE 6, E 1, SE 4, S 0, SW 8, W 3, NW 4, Calm 0 Ground Temperatures: Lowest Grass Minimum: 4.1C on 29th Mean Grass Minimum: 9.3C Lowest Concrete Minimum: 8.1C on 29th Mean Concrete Minimum: 12C Lowest Bare Earth Minimum: 7.1C on 29th Mean Bare Earth Minimum: 9.9C Soil/Earth Temperatures: 5cm mean: 17.9C 10cm mean: 17.7C 20cm mean: 18.3C 30cm mean: 19C 40cm mean: 19.1C 50cm mean: 19.1C 100cm mean: 17.8C Days with: Thunder: 1 Hail less than 0.5cm: 0 Hail greater than/equal to 0.5mm: 0 Snow or snow & rain: 0 Fog: 1 Ground frost: 0 Air frost: 0 Evaporation: Not yet available. Observations made at 0900 UTC. Averages refer to the period 1961-1990.