Averages and extremes
Essex is the driest county in the UK. The driest spot of all is St Osyth, with a mere 507mm per annum on average. Whilst Epping's average is quite a bit more at 679mm, this is still drier than most places in the UK.
Here are the monthly averages based on the Woodberry Down station over 1979-2013:
The wettest year on record was 2000 with 974mm, and the driest was 1983 with 457mm.
On average, it rains on 182 days of the year. In 2012 it rained on 219 days, wherease in 1990 it rained on just 130 days. It has never rained on every day of the month, although in April 1998 it rained on 28 days. Similarly we have never had a completely dry month, although in May 1990 and April 2011 it rained on just 2 days. The longest dry period was from 11th November to 11th December 1989, thirty days without any rain.
The wettest month recorded was October 2000 with 162mm, and the driest was May 1989 with just 1.3mm.
The wettest day on record was 29th July 1987 with a biblical 59.0mm, or more than 2.3 inches.
Epping is in the warmest region of the UK in summer, and one of the coolest for its altitude in winter.
The average daily maximum varies from 6.6°C in January to 22.6°C in July, whilst the average daily minimum is from 1.8°C in January to 12.9°C in both July and August.
The graph below shows how these temperatures vary through the year, and also shows the hottest and coldest temperature in the month averaged over the data period (1979-2013).
The hottest temperature on record was 37.9°C on 10th August 2003. (Sadly there was no weather station operational in Epping when the UK's highest ever temperature of 38.7°C was recorded in Cambridge on 25th July 2019.) A heatwave in July 2006 recorded the highest number of days where the temperature peaked over 30°C, with ten, including six days in a row.
When it comes to "tropical nights", which are nights where the temperature never dips below 20°C, we have recorded just six: in July 1983, August 1990, August 1993, July 1994, August 2004 and July 2006. The warmest of these was the first, when the minimum temperature recorded was 22°C (to the nearest degree).
The coldest temperature recorded was -10°C on each of 1st January 1979 and 12th,13th,14th January 1987 (at that time temperature was recorded to half a degree rather than the tenth recorded latterly). The 12th January 1987 was also our coldest ever day, when the temperature never rose above -8°C. We have recorded several such "ice days" where the temperature never rises above freezing, and three times we have recorded eight ice days in a month: in December 1981, February 1986, and December 2010. The longest continuous run of ice days was in February 1985, when we recorded seven successive freezing days.
Photo: The Green in a snowy January 2010