October seemed like an extension of the Summer with very warm, very dry and very sunny conditions.

Temperatures in the exceptional 6 day hot spell from 28^th September to 3^rd October peaked on 1^st October at 29.0°C, making this the hottest day in October since at least 1972 when records began at this station.

This high temperature set daily maximum temperatures on their way to a monthly mean for this element of 17.5°C, which is 2.8°C above the 30 Year (1981/2010) average and the highest such value in October since at least 1972. In contrast the mean night minimum temperature was 2.0°C above average at 10.1°C. On these figures it was the warmest October since 2006.

The lowest temperature recorded in the month was 1.9°C on 20^th. The lowest grass minimum temperature in October of –1.2°C also occurred on this date. This gave the first ground frost of the Autumn season but no other ground frosts were recorded in the month.

A cooler spell near the end of the month resulted in the lowest day maximum temperature (12.0°C) of the month on 27th, whilst the highest night minimum temperature of the month was 17.5°C on 2^nd.

The mean earth temperature at 30 cms depth as measured daily at 0900 GMT was 13.0°C. The earth temperature reached a highest value of 16.5°C on 1^st, 2^nd, 3^rd and 4^th, and declined to its lowest reading of 9.6°C on 21^st.

This year has been characterised by dry weather and this continued unabated through October to the extent that the rainfall total for the year to the end of October amounted to a meagre 318.8 millimetres, representing only 64% of the 1981/2010 average and a serious rainfall deficiency. Since 1853 only the January/October periods in the years 1921 and 1996 have returned lower rainfall amounts than this year.

The October rainfall total was 21.8 millimetres, which is only 35% of the 1981/2010 average. It was the driest October in Royston since 1995. The number of "rain days" (0.2 millimetres or more) in the month was 11, with rainfall equalling or exceeding 1.0 millimetre on 7 of these days. The wettest day of the month was 8^th with 6.3 millimetres rainfall.

October commenced on a very sunny note with 36.2 hours sunshine being accumulated over the first 4 days of the month. With the last 4 days of September added in this figure becomes a remarkable 77.0 hours.

Total sunshine in October was 175.4 hours, making it the sunniest October since sunshine records are first available in 1998. This was a higher figure than in both July and August! The sunniest day of the month was 1^st with 10.6 hours sunshine. Only 1 day (27^th) in the month was completely sunless, this being only the second such day since 16^th March.

October was a fairly breezy month with a mean wind speed of 7.7 mph being recorded. The highest wind gust speed recorded in the month was 39 mph on 10^th. The highest daily (00/00 GMT) mean wind speed was 16.2 mph on 10^th and the lowest daily mean wind speed was 1.8 mph on 14^th.

The analysis of daily wind directions as observed at 0900 GMT shows a lack of northerly components, as follows: NORTH 0 days, NE 0, E 2, SE 5, S 6, SW 9, W 7, NW 2, and CALM 0.

The mean MSL air pressure in October was 1016.1 mB, which is 2.3 mB above the 30 Year (1981/2010) average. The highest and lowest air pressure values in the month were 1032.0 mB and 992.5 mB on 14^th and 25^th respectively.

The mean relative humidity in the month was 80.2%. The highest daily (00/00 GMT) mean relative humidity in October was 91.7% on 27^th, whilst the lowest daily mean relative humidity was 55.1% on 2^nd. The absolute lowest relative humidity reading in October was 31% at 1335 GMT on 2^nd.

Fog (visibility < 1000 metres @ 0900 GMT) was not observed on any day in October.

Met. Observer, Royston (Iceni) Weather Station

7^th November 2011