July retrospective

The first above average month of the year and well above average at that. Likely to finish just under 2C above average. So far 2013 has seen every month of the year at least 0.5C either above or below average. The pattern matching for July was useless as it did not predict any real chance of very warm weather.

Looking ahead to August

Early indications are that apart from a brief hot spell at the start of the month we could be looking at very average conditions in the first half of the month.

Please place your August CET predictions in this thread. The deadline for entries with no penalty is 23:59 on 31 July. Late entries will be accepted up to 23:59 on 2 August but are subject to a penalty of 0.2C per day for the purposes of the annual competition.

August historic data summary

Here is the usual rundown of historic data for previous years.

We have not had a warm August since 2004 so perhaps we are due one. 2004 saw 17.6C and the previous year saw 18.3C. The last really hot August was 1995 with 19.2C. Three of the last 6 August's saw a CET of 15.3C or 15.4C (2007, 2010 and 2011). In 2012 the CET was a little above average at 16.7C.

Long run averages:
1971-2000: 16.2C
1981-2010: 16.4C
1988-2012: 16.5C

Here is a chart of the July CET since 1961 with a 10 year moving average



Here are some details of what the models and forecasters generally are saying at the moment.

GEFS
http://www.wetterzentrale.de/pics/MT8_London_ens.png
http://www.wetterzentrale.de/pics/MT8_Manchester_ens.png
A hot start potentially but then very average but fairly dry.   

ECM ensembles (De Bilt)
http://www.knmi.nl/exp/pluim/vijftiendaagse/index.php
A very warm start to the month but temperatures then drifting down towards and even below average. 

Weatheronline
http://www.weatheronline.co.uk/cgi-app/reports?MENU=Month-ahead
After a hot start turning cooler but then could see a fair bit of warmer weather from mid month onwards. 

Met office
Contingency planners forecast not yet available but probably will be released on Monday

http://www.metoffice.gov.uk/public/weather/forecast/city-of-london#?tab=regionalForecast
30 day forecast - after a brief hot start generally average temperatures for the rest of the month

Pattern matching (just for fun)

Looking at years since 1900 with a Jun - Jul temperature of 15.5C to 16.5C and July temperature of 17.7C to 18.8C there are only 8 matches. No obvious pattern can be discerned from this. In some years (1900 and 1901) August was very cool, in others (1911 and 1995) it was hot and in others it was about average.

So no clear signal at all this month.

Sticking my neck out and going for...... 19.1c.....

I'll go for just above average I reckon. That's going on the basis of a few hot days and then most of the rest being around average or just above.

I'll go for

16.8C

As your stats show that no month this year has been within 0.5c of average, I'm going with that theme and we're overdue a good August, so I'm going to plump for

17.2c please GW.

Wouldn't it be extraordinary if after an 18c July we had a 14c August...

I'm expecting a rather typical British summer month.  Warm in the south at times, so the CET (2 of which stations are in the south) looks like being a bit above average.

17.4c

17.0C please.

16.9c for me please

Nout overly hot after the first few days but a beautiful dry 7 days coinciding with my hols down in Cornwall

17.2c with average rainfall for most.

17.3c for me please

a very unsettled month cominmg so a coolish 16.2c

17.17 please

Another hot month 18.6c

Just to mess with your minds an estimation using the 12z GFS op run's raw data produces a CET over 20°C to 14th August

The run is considerably hotter than most recent ones, but the changes do start at just four days range... minds messed with now?

20.2 exceptional heat ,excessive sunshine 100f to be broken .

I hope so, but I am going to plump for a more realistic 18.4C.