PITSFORD HALL WEATHER STATION
NORTHAMPTON, UNITED KINGDOM

MONTHLY WEATHER REPORT - NOVEMBER 2004

REVIEW OF THE MONTH

Headline: A grey month with sunshine totals well below normal. A cold snap
introduced some early snow and sharp frosts.

The month began mild with high pressure in charge. However, the high moved
eastwards during the first week to allow an active front to slip southwards
through the county bringing outbreaks of rain. Following the front high
pressure gained ground once again. With the exception of a rather chilly
night on the 5th temperatures were generally respectable with daytime maxima
typically around 12C. However, it remained very grey and overcast. Only the
4th saw any appreciable sunshine.

The 12th saw the high retreat westwards making way for a cold front to sweep
southwards and introduce much colder air across the county. Pressure built
up again giving rise to some pleasant sunshine by day, but some sharp frosts
overnight. The first air frost of the new season at Pitsford was recorded on
the 13th (-0.5C) and the 14th saw a particularly hard frost with grass
minima falling to -6.1C.

Milder air was introduced on the 16th as the winds swung round from the
south, but this was short-lived as fronts worked southwards on the 17th
introducing much colder Artic air. Heavy rain on the leading edge of one of
these fronts turned to snow on the evening of the 18th with some 2cm of
accumulation recorded on the morning of the 19th. Temperatures on the 20th
only reached 3.1C falling away readily to -1.9C with a hard ground frost
(-6.8C). Although further light flurries were noted on the 20th there was no
accumulation. Rather like the start of the month it remained pretty dull
with very little sunshine.

Milder air was introduced from the west on the 21st preceded by rain giving
rise to some icy stretches overnight. The milder weather lasted until the
27th by which time there was a return to more wintry conditions as the winds
veered north-westerly. Daytime maxima remained in single figures and, whilst
the county escaped an air frost, ground frosts returned. Only a few days saw
any significant sunshine.

CLIMATOLOGICAL STATISTICS

Air Temperatures
The Highest Maximum: 13.9C on 17th
The Lowest Maximum: 3.1C on 20th
The Highest Minimum: 9.6C on 7th
The Lowest Minimum: -1.9C on 20th
The Mean Maximum: 10.2C
The Mean Minimum: 4.8C
The Overall Mean: 7.5C
Difference from the Monthly Mean: +0.6C

Relative Humidity:
Highest Relative Humidity (at obs): 100.0% on 21st & 25th
Lowest Relative Humidity (at obs): 78.1% on 13th
Mean Relative Humidity (at obs): 92.4%

Dew Point:
The Highest Dew Point (at obs): 11.0C on 7th
The Lowest Dew Point (at obs): -2.0C on 13th
The Mean Dew Point (at obs): 5.7C

Rainfall:
Total: 39.7mm
Difference from the Monthly Mean: 74.5%
Duration: 44.0hrs
Highest 24 hour fall (obs to obs): 20.5mm on 18th
Rain Days (/=0.2mm): 14
Wet Days (/=1.0mm): 10

Sunshine:
Total Duration of Bright Sunshine: 54.7hrs
Sunniest day: 7.7hrs on 13th
Days without sunshine: 12
Cloud cover (mean at obs): 5.8oktas (72.5%)

Pressure (reduced to sea level):
The Highest Pressu 1038.2mb on 14th
The Lowest Pressu 1012.7mb on 18th
Mean Pressure (recorded at obs): 1022.8mb

Winds
Run of wind (mean over 24 hrs): 108.8miles
Mean daily wind speed: 5.9mph
Highest mean daily wind speed: 10.8mph on 10th & 12th
Run of wind (to date): 3263.0miles
Highest Maximum Gust: 38mph on 12th
Highest wind strength (at obs): 18.4mph on 10th
Mean wind strength (at obs): 6.1mph

Winds from the Following Directions:

N 2 NE 1 E 0 SE 2 S 6 SW 1 W 4 NW 12 Calm 2

Ground Temperatures:
Lowest Grass Minimum: -6.8C on 20th
Mean Grass Minimum: 1.1C
Lowest Concrete Minimum: -2.9C on 14th
Mean Concrete Minimum: 3.4C
Lowest Bare Earth Minimum: -0.7C on 20th
Mean Bare Earth Minimum: 4.9C

Soil/Earth Temperatures:
Surface mean: 7.2C
5cm mean: 7.3C
10cm mean: 7.6C
20cm mean: 8.4C
30cm mean: 8.6C
40cm mean: 8.7C
50cm mean: 9.2C
100cm mean: 10.1C


Days with:
Thunder: 0
Hail less than 0.5mm: 0
Hail greater than/equal to 0.5mm: 0
Snow or snow & rain: 2
Snow lying 2: 19th & 20th
Fog 2
Air frost: 3
Duration of air frost: 10.0hrs
Ground frost: 11

Total Evaporation (tank) 13.45mm