Wednesday, 31 August 2011

The worst summer since 1993....really?

The media have, on recent days, quoted Met Office statistics that suggest this summer has been the poorest since 1993. Undoubtedly, this is true for some parts of the country but for south London it has been the worst summer since 1988 with the summer of 1993 nowhere near as bad. Comparing the two summers we find that in June 1993 the mean temperature was 16.9 C with only 9 days when maxima failed to reach 20 C. There were 5 days with highs above 25 C. Rain fell on 11 days and totalled 42.6 mm. In June 2011 the mean temperature was 15.4 C with 16 days below 20 C and only 3 days above 25 C. Rain fell on 17 days and totalled over 81mm. The July figures are 17.0 and 16.4 C; 10 versus 12 days below 20 C, but 3 against 2 days over 25 C. Rain fell on 16 days in 1993 but only 12 days in 2011. However, the total rainfall was 46 mm in 1993 and 52mm in 2011. With one day to go, August 2011 looks like being a warmer month than August 1993. 16.4 against 17.2. However, the mean maximum temperatures were similar on 21.4 C. In 1993 there were 8 days with maxima below 20 C but there have been 10 this year. There were 3 days with highs above 25 C in 1993 and also in 2011. Rain only fell on 5 days in August 1993 and totalled 30 mm, but August 2011 had 18 rain days totalling 67 mm. It's no contest. In this area the summer of 2011 has been infinitely poorer than that of 1993!

Sunday, 21 August 2011

Summer coming to an end

Like it or not summer is coming to an end, at least meteorologically speaking. The 3 calendar months, June, July and August constitute summer but hopefully there will be plenty more 'summer-like' days to come during the autumn. With 10 days left until the end of the month it looks, assuming that there will be more than 10mm of rain before the 31st, as if this summer will be rated as the poorest since 1988. So how poor was that summer compared to this one. Firstly, in June 1988 there were only 25mm of rain against 82mm this last June. There were only 9 days with rain falling but in June this year there were 17 rain days. However, in June 1988 there were 18 days when the temperature failed to reach 20 C., but this year there were only 16 cool days. In July 1988 there were over 65mm of rain measured compared with 52mm this year. The rain fell on 17 days in 1988 but only on 12 days this year. There were 15 days with maxima below 20C in 1988 but only 10 days this year. August 1988 was not wet, just 29mm recorded but temperatures failed to reach 20C on 9 days. So far this month we have had over 30mm of rain but temperatures have only failed to touch the 20C mark on 3 days. It's still possible that this summer will descend to the level of 1988, but probably not.

Sunday, 14 August 2011

Time for Harvest

It's the time of plenty. What ever the weather has thrown at us in the Spring and Summer, there is usually a happy ending in some form for the farmers and gardeners. In this particular area there is a fine crop of Victoria Plums, although several have rotted on the trees, and the same applies to the apples. The exceptionally dry Spring seems to have had little impact on the fruit and vegetables, but the early summer rains have been more influential. On the positive side, apples, pears and potatos are very large this year. On the negative side, there are plenty of maggots in the apples and many are falling off early. The tomatoes are poor this year, but cucumbers are good. Onions, peppers and chillies are also good, so overall it has probably been a bountiful year. Crab apples are in abundance, so hopefully there will be a return of the Fieldfares this winter. Does it mean another severe winter? One thing for sure, the fruit and vegetables are products of the past weather, and NOT the future weather!

Sunday, 7 August 2011

Downhill to Autumn?

Yesterday, Saturday 6th August, is not a date that rings many bells in the weather fraternity. However, for this little part of south London it is, on average, the warmest day of the year. Okay, so the records only go back 23 years, and it is only warmer than the next warmest day by 0.1 Celsius, but the fact stands. Historically, the early part of August has seen some of the highest temperatures. On August 9th 1911 it was very hot across London, and although some of the maxima on that day were recorded in non-standard conditions, values of 38 were measured at Greenwich, 37 at Isleworth, and 36 at Camden Square, Epsom and South Kensington. However, at Kew, the maximum temperature recorded in a standard Stevenson Screen was only 34.3. Record-breaking heat occurred on the 3rd August 1990, and although only 35.5 was recorded here, there were highs of 36 and 37 in the London area. All these hot days were eclipsed on the 10 August 2003 when this site had a maximum of 36.7 and areas in. and around, London had highs around 37 or 38. This was the hottest day since instrument records began, and on an afternoon when the temperature is failing to reach 20 it seems a far distant memory.