Overview
A rather chilly and often unsettled autumn is expected, with very windy conditions at times, and several chances of early snow in Scotland, and possibly even further south later on in November.
Temperature
Temperatures are expected to be slightly below the long term average over the three month period. The aggregated Central England Temperature (CET) for September, October and November is expected to be -0.25C to -0.75C from the 1971-2000 average.Precipitation
Over the three month period rainfall levels are generally expected to be slightly above average. Overall we expect levels to be between 95% to 115%.
September
Temperature: Close to or slightly below average
Precipitation: Close to average
First half
Starting settled with a good deal of fine weather and close to average temperatures. Through the second week of the month a change to unsettled conditions is expected to develop in the south and west, with the possibility of heavy rainfall in these regions. Probably remaining drier in northern and eastern parts..
Second half
We expect unsettled weather during this period. For a time it is may turn unseasonably cold, with the risk of sleet or snow showers over the Scottish mountains, and possibly even lower levels in Scotland for a time. Overnight frost may extend quite widely and a long way south before temperatures begin to recover and further spells of rain develop October
Temperature: Close to or slightly below average
Precipitation: Above average
First half
Predominantly unsettled conditions, especially to northern areas. Showers or longer spells of rain are expected to develop frequently, with the likelihood of very windy conditions at times. The best of the drier spells are expected in southern and central regions. Temperatures in the south should be close to or slightly above average, but it may well be rather cool in the north Second half
Unsettled weather is expected to affect all areas during this period. Very stormy conditions are expected to develop at times with strong winds and heavy rain at times. Temperatures generally below average in the north making it cold enough at times for sleet or snow over high ground in Scotland. In the south some warmer incursions are likely, but overall temperatures are likely to be November
Temperature: Slightly below or below average
Precipitation: Close to or slightly above average
First half
Changeable weather during much of the forecast period. Temperatures are likely to be close to or slightly below average with the chance of some snow at times over the Scottish hills. Although wet and windy weather is expected at times, there is also a significant chance of high pressure pushing across the UK at times, giving milder and drier interludes.
Second half
Unsettled and at times cold weather is expected to affect most of the country, with widespread showers or longer spells of rain. During the period we expect a significant chance of it turning cold enough at times for heavy snowfall to develop in northern regions, with a chance of wintry conditions extending further south for a time. Temperatures during this period are likely to be below the seasonal average. Key
Temperature
Much above average - the Central England Temperature (CET) is expected to be more than 2C above the 1961-90 average
Above average – the Central England Temperature (CET) is expected to be 1C to 2C above the 1961-90 average
Close to average – the Central England Temperature (CET) is expected to be between 1C below and 1C above the 1961-90 average
Below average – the Central England Temperature (CET) is expected to be 1C to 2C below the 1961-90 average
Much below average - the Central England Temperature (CET) is expected to be more than 2C below the 1961-90 average
Rainfall
Much above average - expected to be more than 150% of the England & Wales Rainfall Series
Above average - expected to be between 125% and 150% of the England & Wales Rainfall Series
Close to average - expected to be between 75% and 125% of the England & Wales Rainfall Series
Below average – expected to be between 75% and 50% of the England & Wales Rainfall Series
Much below average - expected to be below than 50% of the England & Wales Rainfall Series