Daily Report for 11th February 2021

<<Previous Day
Reset
Next Day>>
Measure Value (anomaly) Time Month cumul. Record High Record Low
Minimum Temperature -3.2 °C (-5.3) 02:17 1.2 °C (-1.1) 8.4 °C (+6.3), 2011 -8.1 °C (-10.2), 2012
Maximum Temperature 0.3 °C (-6.8) 13:31 5.2 °C (-2.0) 12.0 °C (+5.0), 2011 0.3 °C (-6.8), 2021
Mean Temperature -1.2 °C (-6.0) 3.5 °C (-1.5) 10.1 °C, 2011 -3.7 °C, 2012
Minimum Humidity 68% 13:34 78% 98%, 2013 50%, 2020
Maximum Humidity 92% 07:31 93% 98%, 2013 77%, 2015
Mean Humidity 80% 87% 98%, 2013 67%, 2020
Minimum Pressure 1026 hPa 00:03 1004 hPa 1035 hPa, 2012 988 hPa, 2014
Maximum Pressure 1030 hPa 12:49 1011 hPa 1036 hPa, 2012 1001 hPa, 2014
Mean Pressure 1028 hPa 1007 hPa 1036 hPa, 2012 996 hPa, 2014
Mean Wind Speed 3.8 mph (-1.3) 4.9 mph (-0.2) 11.8 mph, 2020 0.8 mph, 2012
Maximum Wind Speed 10.9 mph 13:50 13.3 mph 28.6 mph, 2020 6.4 mph, 2012
Maximum Gust 17.1 mph 13:23 20.5 mph 39.2 mph, 2020 8.5 mph, 2012
Mean Wind Direction ESE
Rainfall / Snow-melt approx. 0.5 mm 31.3 mm (194%) 7.6 mm, 2013
Maximum Hourly Rain n/a 1.5, 2018
Maximum 10-min Rain n/a 0.9, 2018
Maximum Rain Rate n/a 13, 2018
Minimum Dew Point -5.5 °C 16:43 -0.6 °C 7.3 °C, 2011 -10.2 °C, 2012
Maximum Dew Point -2.9 °C 08:53 3.1 °C 11.0 °C, 2011 -3.8 °C, 2012
Mean Dew Point -4.3 °C 1.5 °C 9.1 °C, 2011 -7.2 °C, 2012
Measure Value Time Month cumul. Record High Record Low
Night Minimum (21-09) -3.2 °C 02:20 1.9 °C 8.4 °C, 2011 -8.1 °C, 2012
Day Maximum (09-21) 0.3 °C 13:32 5.0 °C 12.0 °C, 2011 0.3 °C, 2021
Max 10m Temp Rise 0.4 °C 12:41 0.4 °C 0.7 °C, 2012 0.1 °C, 2013
Max 1hr Temp Rise 1.1 °C 13:29 1.1 °C 2.6 °C, 2012 0.2 °C, 2013
Max 1hr Hum Rise 6% 17:58 6% 16%, 2018 0%, 2013
Max 10m Temp Fall 0.3 °C 13:49 0.3 °C 1.0 °C, 2018 0.1 °C, 2013
Max 1hr Temp Fall 0.5 °C 01:43 0.9 °C 2.2 °C, 2018 0.2 °C, 2013
Max 1hr Hum Fall 9% 09:49 6% 17%, 2014 0%, 2013
Max 10m Wind Speed 9.0 mph 15:27 10.3 mph 17.8 mph, 2020 5.0 mph, 2016
Minimum Feels-like -7.7 °C 06:52 -3.7 °C 6.5 °C, 2011 -8.4 °C, 2012
Maximum Feels-like -0.4 °C 21:29 4.6 °C 13.7 °C, 2011 -0.4 °C, 2021
Mean Feels-like -4.5 °C 0.7 °C 10.3 °C, 2011 -4.5 °C, 2021
Air-frost Hrs 23 hrs 8 hrs 23 hrs, 2021 0 hrs, 2011
Measure Value (anomaly) Month cumul. Record High Record Low
Temperature Range 3.5 °C (-1.5) 4.0 °C (-0.9) 8.9 °C (+3.9), 2012 0.8 °C (-4.2), 2013
Humidity Range 24% 15% 37%, 2018 0%, 2013
Pressure Range 4 hPa 7 hPa 22 hPa, 2019 1 hPa, 2012
Measure Value [% of max] Month cumul. Record High Record Low
Sun Hours 4.5 [52%]11 hrs (39%) [12%] 8.7 [100%], 2012 0 [0%], 2013
Wet Hours 1
[Mean rain rate: 0.5 mm/h]
39 hrs (191%) [15%] 18, 2013 , 2009
Cloud Cover am: Mostly Cloudy
pm: Mostly Sunny or Hazy
Events Snowfall: ~0.5 cm
Lying Snow (at 09z): ~0.5 cm
Air Frost
Comments overnight sn, lying
Extra Comments
Issues None known
Observer Absent? Yes - observations may be unreliable
Pond Temperature (Heath) 4.5 °C
Notes
Times of extremes are computed using the midpoint of the longest continuous period at that extreme value.
Cumulative anomalies are reported according to the expected value for the month-to-date rather than month-end.
Sun hrs are initially pulled from the official weather station at Heathrow, and later adjusted by hand to reflect local conditions based on webcam observations. Wet hrs are dervied algorithmically from rainfall data, though may be adjusted manually. Cloud cover and Events are manually reported, often with multi-week delays.
View monthly summary

Daily Graph of Conditions

day graph

Webcam Summary of Cloud Conditions

daycamsumFull resolution individual images at up-to 5 minute intervals

Wind rose