PITSFORD HALL WEATHER STATION NORTHAMPTON, UNITED KINGDOM MONTHLY WEATHER REPORT - NOVEMBER 2005 Headline: First half very mild and unsettled. Becoming increasingly wintry and bitterly cold later. The first half of November was generally unsettled as a succession of Atlantic lows passed across northern Britain bringing associated frontal rain and windy conditions to the county. In addition to being wet and windy, the south-westerly airstream maintained temperatures above average for the time of year. The 1st and 2nd saw over 11mm of rain delivered in the 48 hour period from 0900hrs on the 1st with 4mm on the 2nd falling in a little over an hour. A cold front working southwards on the 6th brought a further 10.2mm on just under 3 hours. The 3rd was particularly windy across the whole of the UK with a maximum gust of 40mph recorded at Pitsford. Temperature-wise, it was very mild indeed to begin with. Highs reached 17.8C on the 2nd making this the warmest November day in Northampton since 1969. Overnight frosts were absent apart from a ground frost on the 5th. Despite the unsettled conditions, some reasonable sunshine totals were clocked up on a few days (6.7hrs on the 1st, 4.9hrs on the 9th). High pressure became dominant across the region from the 13th. The weather became more settled. There were some good spells of sunshine, although generally the sunshine at Pitsford was rather hazy and well broken at times. Overnight frosts became a common occurrence aided by clear skies and very light winds. Temperatures on the morning of the 20th fell to -4.0C at Pitsford (the coldest November minimum since 1996) and by day maxima remained fairly modest typically around 6 or 7C. Fog wasn’t so much a problem at Pitsford as it was reported elsewhere, although the 23rd saw some pretty dense and widespread fog which persisted for a good part of the day. The final week saw a marked change in the weather. Low pressure developed over the North Sea becoming rather persistent and drove two cold fronts southwards introducing a blast of cold Arctic air. The 25th struggled to reach 4.0C by day as temperatures the previous night dropped to -3.1C. The front arriving on the 24th produced a squall with gusts reaching 50mph at Pitsford with accompanying hail/ice pellets. Snow showers were anticipated, but only a few light flurries were recorded late on the 28th and no serious problems were created on the roads. As the month came to a close on the 30th a warm front worked in from the west. Warnings were released of black ice on roads during the morning rush hour, although temperatures had risen above freezing before the rain made any impact on the county. Overall this was the coldest November in Northampton since 1999 (5.0C) and the second coldest since 1998 (2.3C). Air Temperatures The Highest Maximum: 17.8C on 2nd The Lowest Maximum: 3.9C on 28th The Highest Minimum: 14.2C on 3rd The Lowest Minimum: -4.0C on 20th The Mean Maximum: 9.7C The Mean Minimum: 2.3C The Overall Mean: 6.0C Difference from the Monthly Mean: -0.9C Relative Humidity: Highest Relative Humidity (at obs): 98.5% on 24th Lowest Relative Humidity (at obs): 83.0% on 30th Mean Relative Humidity (at obs): 94.1% Dew Point: The Highest Dew Point (at obs): 14.1C on 2nd The Lowest Dew Point (at obs): -2.9C on 25th The Mean Dew Point (at obs): 4.1C Rainfall: Total: 34.4mm Difference from the Monthly Mean: 64.4% Duration: 21.5hrs Highest 24 hour fall (obs to obs): 10.2mm on 6th Rain Days (>/=0.2mm): 15 Wet Days (>/=1.0mm): 7 Sunshine: Total Duration of Bright Sunshine: 68.0hrs Sunniest day: 6.7hrs on 1st Days without sunshine: 5 Cloud cover (mean at obs): 4.5oktas (56.3%) Pressure (reduced to sea level): The Highest Pressure: 1039.1 mb on 23rd The Lowest Pressure: 992.6 mb on 26th Mean Pressure (recorded at obs): 1015.7 mb Winds Run of wind (mean over 24 hrs): 141.5miles Mean daily wind speed: 7.7mph Highest mean daily wind speed: 15.4mph on 3rd Run of wind (to date): 4245.9miles Highest Maximum Gust: 50mph on 24th Highest wind strength (at obs): 18.4mph on 26th Mean wind strength (at obs): 7.8mph Winds from the Following Directions: N 5 NE 1 E 0 SE 0 S 6 SW 6 W 2 NW 10 Calm 0 Ground Temperatures: Lowest Grass Minimum: -7.6C on 25th Mean Grass Minimum: -1.5C Lowest Concrete Minimum: -4.5C on 25th Mean Concrete Minimum: 1.5C Lowest Bare Earth Minimum: -3.7C on 25th Mean Bare Earth Minimum: 2.1C Soil/Earth Temperatures: Surface mean: 5.6C 5cm mean: 5.9C 10cm mean: 6.3C 20cm mean: 7.3C 30cm mean: 8.0C 40cm mean: 8.0C 50cm mean: 8.9C 100cm mean: 10.4C Days with: Thunder: 0 Hail less than 0.5mm: 1 Hail greater than/equal to 0.5mm: 0 Snow or snow & rain: 1 Fog 2 Air Frost: 12 Duration of Air Frost: 38.0hrs Ground Frost: 19 Gales: 0 Total Evaporation (tank) 40.41mm