PITSFORD HALL WEATHER STATION NORTHAMPTON, UNITED KINGDOM MONTHLY WEATHER REPORT - AUGUST 2003 Headline: The second driest August in Northampton since 1947 after 1995 and the hottest since 1983. Heatwave raises mean temperatures a good 2C above average. Losses by evaporation exceed rainfall by a factor of 17. Unsettled conditions at the end of July spilled over into the start of August. Low pressure to the north-west was responsible for slight rainfall on the 1st, although conditions had improved markedly on the 2nd. The main feature of the weather in August was the heatwave running from the 3rd right through to the 13th associated with high pressure extending from mainland Europe. Daytime maxima reached the high 20s everyday, exceeding 30C on the 4th, 6th, 9th and 10th. Overnight minima remained high giving some rather uncomfortable nights, particularly between the 10th and 12th when temperatures did not fall below 17C. The highest temperature of 34.1C was recorded on the 9th. The county missed out on its chances to reclaim the UK temperature record as 38.1C was recorded on the 10th at Gravesend. Cloud development and consequent thunderstorm kept temperatures at Pitsford pegged back at just 30.9C. Between 1911 and 1990 the UK temperature record of 36.7C was held by Raunds, until beaten by Cheltenham (37.1C). The thundery activity on the 10th delivered 5.9mm of rain at Pitsford and with the exception of the small amounts (0.2mm or less) on the 1st, 27th and 28th, was the only significant 'wet day' in August making this second the driest August in Northampton since 1947 after 1995. A rather changeable period ensued from the 14th. Although dry throughout the county, some rainfall was recorded in western and southern areas. Yet it remained reasonably warm with daytime maxima reaching the low to mid 20s. Some good sunshine totals were recorded between the 14th and 16th. Some fronts gave further light showers in some places on the 21st and 22nd, yet again escaping the county altogether. As the month came to a close in the final week, high pressure developing south of Iceland coupled with a Scandinavian low fed a northerly airflow across the UK bringing temperatures down and for the final four days temperatures fell just short of the 20C mark. Low pressure tracking up from Biscay brought spells of rain on the 27th and 28th, but as previously mentioned amounts were slight. In addition to the drought, this was Northampton's warmest August since 1983 and the maxima of 34.1C on the 9th was the warmest August day in Northampton since 1990. Losses by evaporation exceeded rainfall replenishment by a factor of 17 resulting in significant reductions in reservoir levels across the county. Air Temperatures The Highest Maximum: 34.1C on 9th The Lowest Maximum: 18.0C on 28th The Highest Minimum: 18.1C on 11th The Lowest Minimum: 5.9C on 30th The Mean Maximum: 24.6C The Mean Minimum: 13.2C The Overall Mean: 18.9C Difference from the Monthly Mean: 2.3C Relative Humidity: Highest Relative Humidity (at 0900): 93.1% on 1st Lowest Relative Humidity (at 0900): 55.9% on 16th Mean Relative Humidity (at 0900): 73.5% Dew Point: The Highest Dew Point (at 0900): 19.1C on 9th The Lowest Dew Point (at 0900): 8.7C on 31st The Mean Dew Point (at 0900): 14.2C Rainfall: Total: 6.3mm Difference from the Monthly Mean: 12.9% Duration: 4.9hrs Highest 24 hour fall (from 0900): 5.9mm on 10th Rain Days (>/=0.2mm): 2 Wet Days (>/=1.0mm): 1 Sunshine: Total Duration of Bright Sunshine: 223.9hrs Sunniest day: 12.6hrs on 2nd Sunless days: 1 Cloud cover (mean at 0900): 5.3oktas (66.3%) Pressure (reduced to sea level at 0900): The Highest Pressure: 1023.9mb on 5th The Lowest Pressure: 1006.4mb on 29th Mean Pressure: 1017.9mb Winds Run of wind (mean over 24 hrs): 81.3miles Mean daily wind speed: 4.4mph Highest mean daily wind speed: 9.0mph on 21st Run of wind (to date): 2519.9miles Highest Maximum Gust: 29mph on 29th Highest wind strength (at 0900): 11.5mph on 29th Mean wind strength (at 0900): 4.7mph Winds from the Following Directions: N 3 NE 6 E 5 SE 0 S 1 SW 1 W 0 NW 12 Calm 3 Ground Temperatures: Lowest Grass Minimum: 2.6C on 30th Mean Grass Minimum: 10.7C Lowest Concrete Minimum: 6.1C on 30th Mean Concrete Minimum: 13.9C Lowest Bare Earth Minimum: 6.6C on 30th Mean Bare Earth Minimum: 13.5C Soil/Earth Temperatures: Surface mean: 20.2C 5cm mean: 18.8C 10cm mean: 19.4C 20cm mean: 19.8C 30cm mean: 19.8C 40cm mean: 19.8C 50cm mean: 19.9C 100cm mean: 18.2C Days with: Thunder: 1 Hail less than 0.5mm: 0 Hail greater than/equal to 0.5mm: 0 Snow or snow & rain: 0 Fog: 0 Ground frost: 0 Air frost: 0 Gales: 0 Total Evaporation (tank) 107.87mm