Daily Report for 23rd September 2010

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Measure Value (anomaly) Time Month cumul. Record High Record Low
Minimum Temperature 12.2 °C (+1.3) 23:52 11.4 °C (-0.4) 15.2 °C (+4.3), 2024 8.1 °C (-2.8), 2014
Maximum Temperature 17.4 °C (-0.5) 16:23 19.2 °C (-0.2) 20.7 °C (+2.8), 2021 11.9 °C (-6.0), 2012
Mean Temperature 15.4 °C (+0.4) 15.4 °C (-0.3) 16.7 °C, 2024 10.1 °C, 2012
Minimum Humidity 76% 20:03 56% 78%, 2024 44%, 2016
Maximum Humidity 93% 14:10 90% 98%, 2012 82%, 2017
Mean Humidity 86% 74% 91%, 2013 63%, 2016
Minimum Pressure 1002 hPa 22:27 1013 hPa 1025 hPa, 2009 997 hPa, 2012
Maximum Pressure 1013 hPa 00:32 1018 hPa 1031 hPa, 2018 1006 hPa, 2020
Mean Pressure 1008 hPa 1015 hPa 1026 hPa, 2009 1001 hPa, 2020
Mean Wind Speed 4.3 mph (+0.4) 4.8 mph (+0.9) 6.3 mph, 2019 1.2 mph, 2013
Maximum Wind Speed 12.5 mph 12.5 mph 16.0 mph, 2020 5.9 mph, 2013
Maximum Gust 19.5 mph 17:56 18.3 mph 26.5 mph, 2024 7.6 mph, 2013
Mean Wind Direction SW
Rainfall 8.2 mm 27.0 mm (70%) 31.4 mm, 2024
Maximum Hourly Rain 3.8 mm 13:10 16.5 mm, 2024
Maximum 10-min Rain 1.1 mm 12:45 6.5 mm, 2024
Maximum Rain Rate 10 mm/h 13:10 72 mm/h, 2024
Minimum Dew Point 10.8 °C 21:51 8.1 °C 13.5 °C, 2024 3.7 °C, 2012
Maximum Dew Point 15.6 °C 14:45 13.3 °C 16.5 °C, 2024 8.7 °C, 2018
Mean Dew Point 13.1 °C 10.6 °C 14.9 °C, 2024 7.4 °C, 2016
Measure Value Time Month cumul. Record High Record Low
Night Minimum (21-09) * 14.7 °C * 11.8 °C 15.6 °C, 2020 8.1 °C, 2014
Day Maximum (09-21) 17.4 °C 19.2 °C 20.7 °C, 2021 11.8 °C, 2012
Max 10m Temp Rise 0.6 °C 08:30 0.6 °C 0.8 °C, 2011 0.2 °C, 2018
Max 1hr Temp Rise 2.2 °C 08:59 2.4 °C 3.8 °C, 2016 1.0 °C, 2018
Max 1hr Hum Rise 8% 21:04 7% 13%, 2019 3%, 2022
Max 10m Temp Fall 0.5 °C 20:26 0.4 °C 0.6 °C, 2020 0.2 °C, 2015
Max 1hr Temp Fall 1.7 °C 20:48 1.6 °C 2.3 °C, 2016 0.7 °C, 2015
Max 1hr Hum Fall 8% 09:19 10% 15%, 2015 2%, 2012
Max 10m Wind Speed 8.7 mph 20:04 8.7 mph 12.1 mph, 2024 4.1 mph, 2013
Minimum Feels-like 13.9 °C 23:46 12.0 °C 18.4 °C, 2024 5.4 °C, 2023
Maximum Feels-like 21.6 °C 15:53 21.3 °C 25.5 °C, 2021 14.0 °C, 2012
Mean Feels-like 18.3 °C 17.2 °C 20.6 °C, 2024 10.4 °C, 2012
Air-frost Hrs 0 hrs 0 hrs 0 hrs, 2009 0 hrs, 2009
Measure Value (anomaly) Month cumul. Record High Record Low
Temperature Range 5.2 °C (-1.8) 7.8 °C (+0.2) 11.1 °C (+4.1), 2016 3.4 °C (-3.6), 2024
Humidity Range 17% 34% 47%, 2014 15%, 2020
Pressure Range 11 hPa 6 hPa 22 hPa, 2012 2 hPa, 2009
Measure Value [% of max] Month cumul. Record High Record Low
Sun Hours 0.5 [5%]111 hrs (97%) [42%] 10 [91%], 2016 0 [0%], 2009
Wet Hours 4
[Mean rain rate: 2.0 mm/h]
13 hrs (41%) [2.4%] 10, 2012 0, 2009
Cloud Cover am: Mostly Cloudy transitioned to Overcast
pm: Overcast transitioned to Mostly Cloudy
Events None
Comments 10-13 Moderate Rain; 20 Light Shower
Extra Comments
Issues None known
Observer Absent? No
Pond Temperature (Heath) 0.0 °C
Notes
Detailed daily weather report for Hampstead nw3 in London on 23rd September 2010.
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 derived based on analysis of webcam observations, but may use data from our closest site, Heathrow, when needed.
Wet hrs are dervied algorithmically from rainfall data, though may be adjusted manually.
Rainfall totals may be manually adjusted after the fact to correct delayed or erroneous data.
Cloud cover and Events are manually reported, often with multi-week delays.
Data is generally reliable and accurate but should always be viewed with some quantity of salt to hand.
View monthly summary

Daily Graph of Conditions

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Webcam Summary of Cloud Conditions

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Wind rose