The splendid weather has to end

Although no records have been broken, this month will be remembered for many dry, sunny and pleasantly warm days, and of course the exceptional heat at the beginning of October. At the moment it is the driest October since 1978, although rain tonight looks like changing that. October 1978, despite being a dry month, was not particularly sunny, and although days were often warm, nights were sometimes quite chilly. The cool nights have been a feature of recent temperature statistics this October, and that has dragged down the temperature averages. Therefore, it seems unlikely that this month will hold on to it's 5th warmest ranking (since 1900) . However, the 4 mildest Octobers have all occurred during the last 16 years and Edwardian or Georgian London would have been very pleased with this mild, bright and smog-free month!

Receding blue skies

After the amazingly blue skies of yesterday, the clouds have returned. Mustn't grumble, though. This October continues to be the warmest for at least a 100 years but will it last? Well, maybe! Although there have been some fairly warm days, the nights have been chilly under the starry skies. The first real ground frost of the autumn occurred last night, but although there may be some more chilly nights to come, the forecast charts suggest a much more unsettled and windy second half to the month. It should mean maximum temperatures near, or slightly above average, but with nights generally much milder than average under the cloudy skies. So, probably a top 10 spot as a mild October, but number 1 will be more difficult. The mildest October, 2001, only had a monthly minimum temperature of 4.9 (0.7 so far this month!), and there were just 9 days with minimum temperatures below 10 Celsius!

The end of the dry spell

After 17 days without measurable rain, the 0.2 millimetres that fell yesterday evening was enough to break the dry spell. Most years have a prolonged dry spell (15 days or longer) with Spring and Autumn months most likely to see one. September and the beginning of October have had 3 dry spells in recent years. 1997, 2002 and 2007 each had between 15 and 17 consecutive dry days, and back in 1969 only 3 millimetres of rain fell throughout September. The most prolonged autumn dry spell in the London area occurred from the 14th September to 9th October 1921 (26 days). However, there were several lengthy dry periods that began in August, notably 23rd August to 28th September 1929, and 15th August to 20th September 1959, both 37 days. In the extended good summer of 1959 there was a further 17 days of dry weather from the 23rd September until 9th October.