Daily Report for 21st June 2023

<<Previous Day
Reset
Next Day>>
Measure Value (anomaly) Time Month cumul. Record High Record Low
Minimum Temperature 15.8 °C (+3.4) 05:40 12.4 °C (+0.7) 15.8 °C (+3.4), 2023 9.4 °C (-3.0), 2022
Maximum Temperature 25.7 °C (+4.3) 15:36 24.2 °C (+3.6) 33.0 °C (+11.6), 2017 13.7 °C (-7.7), 2021
Mean Temperature 21.0 °C (+3.8) 18.2 °C (+2.2) 24.5 °C, 2017 12.6 °C, 2021
Minimum Humidity 54% 14:55 52% 85%, 2021 34%, 2018
Maximum Humidity 90% 05:25 87% 94%, 2012 69%, 2014
Mean Humidity 71% 70% 88%, 2021 51%, 2014
Minimum Pressure 1012 hPa 00:05 1017 hPa 1023 hPa, 2009 1001 hPa, 2012
Maximum Pressure 1020 hPa 23:43 1021 hPa 1030 hPa, 2018 1011 hPa, 2011
Mean Pressure 1017 hPa 1019 hPa 1026 hPa, 2018 1006 hPa, 2012
Mean Wind Speed 5.7 mph (+1.3) 5.2 mph (+0.8) 8.2 mph, 2011 0.9 mph, 2022
Maximum Wind Speed 12.6 mph 15:17 13.9 mph 19.7 mph, 2011 7.5 mph, 2010
Maximum Gust 19.6 mph 11:52 21.1 mph 32.9 mph, 2011 10.6 mph, 2010
Mean Wind Direction W
Rainfall 0.0 mm 21.6 mm (66%) 6.9 mm, 2012
Maximum Hourly Rain n/a 4.3, 2012
Maximum 10-min Rain n/a 4.3, 2012
Maximum Rain Rate n/a 90, 2013
Minimum Dew Point 14.2 °C 04:52 9.1 °C 14.2 °C, 2023 3.7 °C, 2018
Maximum Dew Point 16.4 °C 11:05 15.5 °C 18.9 °C, 2017 9.2 °C, 2018
Mean Dew Point 15.3 °C 12.3 °C 16.1 °C, 2017 5.9 °C, 2018
Measure Value Time Month cumul. Record High Record Low
Night Minimum (21-09) 15.8 °C 05:40 12.4 °C 15.8 °C, 2023 9.4 °C, 2022
Day Maximum (09-21) 25.7 °C 15:37 24.2 °C 33.0 °C, 2017 13.7 °C, 2021
Max 10m Temp Rise 0.7 °C 13:00 0.7 °C 1.0 °C, 2012 0.2 °C, 2021
Max 1hr Temp Rise 1.8 °C 08:47 2.5 °C 3.3 °C, 2022 0.6 °C, 2021
Max 1hr Hum Rise 6% 22:29 10% 16%, 2014 4%, 2021
Max 10m Temp Fall 0.6 °C 15:55 0.7 °C 0.8 °C, 2013 0.3 °C, 2016
Max 1hr Temp Fall 1.3 °C 21:26 2.2 °C 2.7 °C, 2013 0.7 °C, 2021
Max 1hr Hum Fall 9% 13:29 11% 16%, 2015 4%, 2021
Max 10m Wind Speed 8.5 mph 17:27 10.2 mph 15.0 mph, 2011 3.7 mph, 2022
Minimum Feels-like 19.3 °C 05:40 13.2 °C 19.3 °C, 2023 9.7 °C, 2022
Maximum Feels-like 30.5 °C 15:30 28.0 °C 38.7 °C, 2017 16.0 °C, 2021
Mean Feels-like 25.2 °C 20.7 °C 29.3 °C, 2017 14.2 °C, 2021
Air-frost Hrs 0 hrs 0 hrs 0 hrs, 2009 0 hrs, 2009
Measure Value (anomaly) Month cumul. Record High Record Low
Temperature Range 9.9 °C (+0.9) 11.8 °C (+2.9) 17.4 °C (+8.4), 2017 2.5 °C (-6.5), 2021
Humidity Range 36% 35% 57%, 2022 8%, 2021
Pressure Range 8 hPa 4 hPa 10 hPa, 2012 2 hPa, 2010
Measure Value [% of max] Month cumul. Record High Record Low
Sun Hours 10 [66%]189 hrs (140%) [60%] 14 [93%], 2017 0 [0%], 2021
Wet Hours 08 hrs (31%) [1.6%] 6, 2021 0, 2009
Cloud Cover unknown
Events None
Comments blr
Extra Comments
Issues None known
Observer Absent? No
Pond Temperature (Heath) 22.0 °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