Spring - Full steam ahead

Just when it looked as Spring was going to be late this year the weather changed and Spring is accelerating forward. It has not been unusual in recent years for nature to get a big boost from March warmth. In the last 23 years the mean temperature for March has been 8.0 Celsius. Prior to 1989 this figure had been exceeded on only 13 occasions since the year 1900. Since 1989 there have been 14 occasions when March has had a mean temperature higher than 8.0 Celsius. So far this March (excluding today) the mean temperature has been 8.2 Celsius but the forecast charts suggest it may eventually be much higher than that. To claim a 'top ten' position the mean temperaturee has to be 8.7 Celsius or higher. This figure was last exceeded in March 2003 with a mean temperature of 9.0 Celsius. This placed March 2003 at number 6 in the list dating back to 1900. The one to beat is March 1957 (9.9C). On this day in 1957 the temperature in London exceeded 19 Celsius and even the coldest day of the month had a maximum temperature above 9 Celsius. The month was not frost-free, though. On the morning of the 4th a temperature of minus 1 Celsius was recorded.

Soft January days

At the moment, with a third of the month gone, this January is the mildest since before 1900. It hasn't been wall to wall sunshine, but the soft grey clouds with chinks of blue showing through are nevertheless uplifting when accompanied by a temperature that frequently tops 10 Celsius. Since 1900, a total of 4 out of the top 10 mildest Januaries have occurred during the last 10 years and only 2 of the mildest Januaries occurred before 1974. The mildest January, 2007, had maxima above 10 Celsius continuously from the 3rd to the 20th, and on 6 days the high topped 13 Celsius, a figure we haven't reached this January. The highest value was 14.2 Celsius on the 18th, a day of destructive winds when a gust of 58 knots (64 mph) was recorded here. Although the month was record-breakingly mild, it was not without its wintery moments. Sleet or snow fell on 5 days towards the end of the month and on the 24th there were 3 centimetres of snow carpeting the garden for most of the morning.

Dry, but getting wetter!

The 23rd of May, the sun is shining, but rain over the weekend has reduced the Spring deficit and it remains uncertain whether the 'record dry Spring will become a reality. A mere 15mm will now take the 3 month total past that achieved in Spring 1976 but there are only 9 rain days left! Let's have a look at the latest charts. At the moment the radar shows a band of rain over Wales and that's forecast to weaken considerably as it moves southeast. Probably 1mm at most before it clears. Tomorrow (24th). Only an outside chance of a shower. 25th suggests a weak front late in the day or overnight, again less than 1mm. So, 6 days to go and 13mm. 26th will probably be showery, typically 2-5mm, with a ridge of high pressure helping to produce a dry day on the 27th. The 28th could well be a wet day 5-10mm, possibly more! Back to showers and around 2mm on the 29th followed by more substantial rain on the 30th (5-10mm) and then showers again on the 31st (about 2mm). Best estimate would suggest the record will be missed by close on 3mm. Bad news for the thrill-seeking statisticians. Great news for the gardeners!

A Rare 'Since Records Began'.

After 20 years of noting the daily weather, it becomes increasingly rare for new records to appear. Yesterday was one of those record-breaking days. The rainfall total, 22.0mm, beat the existing February record, set on the 24th in 2000, when 21.1mm fell. High daily rainfall during February is quite unusual, and in this area a total of 20mm appears to have been exceeded on only 3 more occasions. Namely, in the years

1925, 1933 and 1951. The wettest day was the 13th February 1925 when between 25 and 30mm of rain fell locally. Of interest, but not statistically significant so early in the month, a wet February in this area, with rainfall over 70mm, has only been accompanied by a cold February, with a mean temperature below 4.0 C, on one occasion since 1890, and that was in 1900! Another 18mm is needed to keep the rainfall part of the record at this site, and with a mean temperature of 1.3C, some mild days (and nights) are needed to spoil the other half of the potentially record-breaking equation.