Daily Report for 28th December 2019

<<Previous Day
Reset
Next Day>>
Measure Value (anomaly) Time Month cumul. Record High Record Low
Minimum Temperature 6.9 °C (+4.1) 01:26 4.1 °C (+0.9) 9.4 °C (+6.6), 2015 -1.3 °C (-4.1), 2014
Maximum Temperature 9.0 °C (+1.8) 15:55 9.3 °C (+1.4) 13.7 °C (+6.5), 2015 2.6 °C (-4.6), 2020
Mean Temperature 8.1 °C (+2.9) 6.9 °C (+1.1) 11.5 °C, 2015 1.1 °C, 2016
Minimum Humidity 84% 17:57 78% 90%, 2020 60%, 2011
Maximum Humidity 93% 01:24 94% 98%, 2009 83%, 2016
Mean Humidity 88% 87% 93%, 2020 74%, 2011
Minimum Pressure 1036 hPa 00:11 1000 hPa 1041 hPa, 2016 972 hPa, 2020
Maximum Pressure 1038 hPa 11:20 1013 hPa 1045 hPa, 2016 983 hPa, 2020
Mean Pressure 1037 hPa 1008 hPa 1043 hPa, 2016 976 hPa, 2020
Mean Wind Speed 3.9 mph (-1.2) 5.8 mph (+0.7) 8.2 mph, 2011 0.5 mph, 2016
Maximum Wind Speed 10.9 mph 19:50 15.0 mph 18.1 mph, 2011 4.7 mph, 2016
Maximum Gust 17.3 mph 19:01 24.6 mph 27.9 mph, 2011 7.3 mph, 2016
Mean Wind Direction SSW
Rainfall 0.0 mm 92.4 mm (186%) 4.4 mm, 2010
Maximum Hourly Rain n/a 2.2, 2010
Maximum 10-min Rain n/a 0.8, 2010
Maximum Rain Rate n/a 20, 2010
Minimum Dew Point 5.4 °C 23:50 2.3 °C 5.8 °C, 2015 -4.3 °C, 2014
Maximum Dew Point 7.0 °C 10:15 7.1 °C 11.1 °C, 2012 0.7 °C, 2014
Mean Dew Point 6.3 °C 4.9 °C 7.7 °C, 2012 -2.1 °C, 2014
Measure Value Time Month cumul. Record High Record Low
Night Minimum (21-09) * 6.2 °C * 21:23 4.8 °C 9.4 °C, 2015 -1.2 °C, 2009
Day Maximum (09-21) 9.0 °C 15:41 9.1 °C 13.7 °C, 2015 2.5 °C, 2020
Max 10m Temp Rise 0.2 °C 01:32 0.3 °C 0.5 °C, 2012 0.2 °C, 2010
Max 1hr Temp Rise 0.5 °C 02:19 1.1 °C 1.6 °C, 2014 0.5 °C, 2019
Max 1hr Hum Rise 2% 05:22 5% 6%, 2014 2%, 2019
Max 10m Temp Fall 0.2 °C 00:45 0.4 °C 0.5 °C, 2014 0.2 °C, 2009
Max 1hr Temp Fall 0.5 °C 19:04 1.3 °C 2.4 °C, 2014 0.2 °C, 2018
Max 1hr Hum Fall 2% 02:23 6% 8%, 2014 1%, 2010
Max 10m Wind Speed 8.3 mph 19:52 11.4 mph 12.4 mph, 2012 3.5 mph, 2016
Minimum Feels-like 3.2 °C 01:07 0.1 °C 7.3 °C, 2015 -6.2 °C, 2017
Maximum Feels-like 8.8 °C 12:46 9.0 °C 13.9 °C, 2015 2.2 °C, 2020
Mean Feels-like 6.6 °C 4.9 °C 11.7 °C, 2015 -2.2 °C, 2017
Air-frost Hrs 0 hrs 0 hrs 6 hrs, 2016 0 hrs, 2010
Measure Value (anomaly) Month cumul. Record High Record Low
Temperature Range 2.1 °C (-2.3) 5.2 °C (+0.4) 8.2 °C (+3.8), 2012 2.1 °C (-2.3), 2019
Humidity Range 9% 15% 32%, 2014 3%, 2016
Pressure Range 2 hPa 13 hPa 23 hPa, 2014 2 hPa, 2019
Measure Value [% of max] Month cumul. Record High Record Low
Sun Hours 0 [0%]70 hrs (135%) [35%] 7.2 [103%], 2017 0 [0%], 2010
Wet Hours 0105 hrs (188%) [16%] 6, 2012 0, 2009
Cloud Cover Overcast
Events None
Comments -
Extra Comments
Issues None known
Observer Absent? Yes - observations may be unreliable
Pond Temperature (Heath) 5.5 °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