PITSFORD HALL WEATHER STATION
NORTHAMPTON, UNITED KINGDOM

MONTHLY WEATHER REPORT - OCTOBER 2003

Headline: A cold month with temperatures below average. Anticyclonic 
around mid-month, but particularly unsettled and wet in the final week.

The month opened with the weather being influenced by a low pressure 
centred over Biscay. A warm, but rather changeable, few days marked 
the start of October with light showery outbreaks.

Further depressions then tracked southwards from Iceland maintaining 
the unsettled weather. Winds were mainly north or north-westerly 
giving a cool feel with air temperatures falling close to freezing 
on the 5th, but low enough to give the first fairly widespread ground 
frost of the autumn season (-2.4C at Pitsford). Again there were 
frequent showers, rather heavy on the 6th with 3.7mm falling in a 
little over an hour, but some good sunny spells developed in between.

Anticyclonic conditions began to prevail from the 11th onwards. 
High pressure developed first over Scandinavia and then migrated 
southwards to Denwark and thence to Iceland. Winds generally were 
from an easterly quadrant, south-east at first and then as they 
backed more north-easterly temperatures began to fall. 

It became unsettled once more from the 20th. Low pressure over 
southern Scandinavia  migrated south-westwards maintaining the flow 
of north or north-easterly winds across the region keeping 
temperatures some way below the average for late October. The 21st 
and 22nd were particularly cold days, both recording air frosts 
(-0.9C and -0.5C respectively). The grass minimum on the 21st fell 
to -4.5C. Showers through this period fell as snow or sleet in some 
places, but there were no such reports in Northamptonshire.

Short-lived high pressure on the 26th and 27th gave a couple of 
settled days with good autumnal sunshine by day, but some widespread 
ground frosts overnight. This settled spell was the prelude to a 
rather wild end to the month. Active Atlantic fronts worked eastwards 
bringing some of the most substantial rainfall seen across the county 
since the final week in July. 12.7mm was delivered in 17.7hrs on the 
28th and a further 18.3mm fell over 17.4hrs on the 30th. However, 
this rainfall did little to assist the replenishment of already 
severly depleted reservoir at Ravensthorpe.

A feature of the final week in addition to the rain was the solar 
storm giving rise to rather spectacular aurora in the night sky.


Air Temperatures				
The Highest Maximum:			20.8C	on	9th
The Lowest Maximum:			7.9C	on	22nd
The Highest Minimum:			11.5C	on	10th
The Lowest Minimum:			-0.9C	on	21st
The Mean Maximum:			13.7C		
The Mean Minimum:			4.7C		
The Overall Mean:			9.2C		
Difference from the Monthly Mean:	-1.1C		
				
Relative Humidity:				
Highest Relative Humidity (at 0900):	98.6%	on	29th & 31st
Lowest Relative Humidity (at 0900):	70.2%	on	9th
Mean Relative Humidity (at 0900):	87.7%		
				
Dew Point:				
The Highest Dew Point (at 0900):	12.1C	on	3rd
The Lowest Dew Point (at 0900):		-0.2C	on	5th & 21st
The Mean Dew Point (at 0900):		6.1C		
				
Rainfall:				
Total:					45.8mm		
Difference from the Monthly Mean:	83.0%		
Duration:				46.9hrs		
Highest 24 hour fall (from 0900):	18.3mm	on	30th
Rain Days (>/=0.2mm):			13			
Wet Days (>/=1.0mm):			7			
				
Sunshine:				
Total Duration of Bright Sunshine:	153.1hrs		
Sunniest day:				8.6hrs	on	15th & 18th
Sunless days:				2
Cloud cover (mean at 0900):		4.3oktas (53.8%)	
				
Pressure (reduced to sea level):				
The Highest Pressure:			1030.7mb   on	16th
The Lowest Pressure:			975.5mb	   on	31st
Mean Pressure (recorded at 0900):	1013.6mb		
				
Winds				
Run of wind (mean over 24 hrs):		120.4miles		
Mean daily wind speed:			6.5mph	
Highest daily wind speed:		11.3mph on 	17th	
Run of wind (to date):			3731.0miles		
Highest Maximum Gust:			40mph	on	7th
Highest wind strength (at 0900):	16.1mph	on	17th
Mean wind strength (at 0900):		7.3mph		
				
Winds from the Following Directions:				

N 2 NE 9 E 3 SE 1 S 2 SW 0 W 2 NW 10 Calm 2		
				
Ground Temperatures:			 	
Lowest Grass Minimum:			-4.8C	on	25th
Mean Grass Minimum:			1.1C		
Lowest Concrete Minimum:		-1.4C	on	25th
Mean Concrete Minimum:			3.9C		
Lowest Bare Earth Minimum:		-1.3C	on	25th
Mean Bare Earth Minimum:		4.1C		
				
Soil/Earth Temperatures:		 		
Surface mean:				8.0C		
5cm mean:				8.2C		
10cm mean:				8.6C		
20cm mean:				9.7C		
30cm mean:				10.3C		
40cm mean:				10.3C		
50cm mean:				11.0C		
100cm mean:				12.1C		
				
				
Days with:				
Thunder:				0			
Hail less than 0.5mm:			0			
Hail greater than/equal to 0.5mm:	0			
Snow or snow & rain:			0			
Fog:					0	
Air Frost:				2
Duration of Air Frost:			3hrs
Ground Frost:				11
				
						
Total Evaporation (tank)		36.5mm