Daily Report for 18th October 2009

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Measure Value (anomaly) Time Month cumul. Record High Record Low
Minimum Temperature 2.8 °C (-5.7) 8.6 °C (-0.6) 16.4 °C (+7.9), 2014 2.8 °C (-5.7), 2009
Maximum Temperature 12.4 °C (-2.2) 15.5 °C (-0.1) 19.5 °C (+4.9), 2014 12.3 °C (-2.3), 2020
Mean Temperature 7.1 °C (-4.0) 11.8 °C (-0.4) 17.8 °C, 2014 7.1 °C, 2009
Minimum Humidity 54% 62% 84%, 2021 42%, 2011
Maximum Humidity 86% 91% 98%, 2013 84%, 2016
Mean Humidity 74% 78% 92%, 2021 66%, 2011
Minimum Pressure 1020 hPa 1017 hPa 1026 hPa, 2022 984 hPa, 2023
Maximum Pressure 1028 hPa 1023 hPa 1030 hPa, 2022 1003 hPa, 2019
Mean Pressure 1024 hPa 1020 hPa 1028 hPa, 2022 996 hPa, 2023
Mean Wind Speed 1.2 mph (-2.9) 3.3 mph (-0.8) 9.0 mph, 2016 1.0 mph, 2020
Maximum Wind Speed 5.5 mph 9.6 mph 23.1 mph, 2016 5.5 mph, 2009
Maximum Gust 7.5 mph 14.3 mph 35.5 mph, 2016 7.5 mph, 2009
Mean Wind Direction W
Rainfall 0.0 mm 19.0 mm (50%) 11.0 mm, 2023
Maximum Hourly Rain n/a 4, 2017
Maximum 10-min Rain n/a 2.4, 2019
Maximum Rain Rate n/a 66, 2019
Minimum Dew Point 1.0 °C 5.3 °C 14.8 °C, 2014 -0.5 °C, 2011
Maximum Dew Point 4.0 °C 10.6 °C 15.9 °C, 2014 4.0 °C, 2009
Mean Dew Point 2.5 °C 8.0 °C 15.4 °C, 2014 2.5 °C, 2009
Measure Value Time Month cumul. Record High Record Low
Night Minimum (21-09) 2.8 °C 9.1 °C 16.2 °C, 2014 2.8 °C, 2009
Day Maximum (09-21) 12.4 °C 15.2 °C 19.5 °C, 2014 12.3 °C, 2020
Max 10m Temp Rise n/a 0.0 °C 0.9, 2022 0.2, 2012
Max 1hr Temp Rise n/a 0.0 °C 3.3, 2022 0.8, 2016
Max 1hr Hum Rise n/a 0% 10, 2011 3, 2021
Max 10m Temp Fall n/a 0.0 °C 0.8, 2019 0.1, 2017
Max 1hr Temp Fall n/a 0.0 °C 1.6, 2019 0.2, 2017
Max 1hr Hum Fall n/a 0% 14, 2016 4, 2023
Max 10m Wind Speed n/a 4.2 mph 18.2, 2016 0.2, 2020
Minimum Feels-like 0.0 °C 00:00 5.1 °C 20.2 °C, 2014 0.0 °C, 2009
Maximum Feels-like 0.0 °C 00:00 9.9 °C 23.8 °C, 2014 0.0 °C, 2009
Mean Feels-like 0.0 °C 7.8 °C 22.0 °C, 2014 0.0 °C, 2009
Air-frost Hrs 0 hrs 0 hrs 0 hrs, 2009 0 hrs, 2009
Measure Value (anomaly) Month cumul. Record High Record Low
Temperature Range 9.6 °C (+3.5) 6.9 °C (+0.5) 10.5 °C (+4.4), 2022 3.1 °C (-3.0), 2014
Humidity Range 32% 29% 45%, 2011 14%, 2021
Pressure Range 8 hPa 6 hPa 26 hPa, 2023 3 hPa, 2020
Measure Value [% of max] Month cumul. Record High Record Low
Sun Hours 3 [32%]50 hrs (70%) [28%] 8 [85%], 2011 0 [0%], 2017
Wet Hours 020 hrs (71%) [4.7%] 7, 2023 0, 2009
Cloud Cover not available
Events None
Comments -
Extra Comments
Issues MISSING DATA: 3rd - 6th, 11th - 21st. Figures obtained from local PWSs, Hampstead and METARs, with wind data obtained by regressional analysis from London AP METARs.
Observer Absent? Yes - observations may be unreliable
Pond Temperature (Heath) 0.0 °C
Notes
Detailed daily weather report for Hampstead nw3 in London on 18th October 2009.
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.
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Daily Graph of Conditions

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Webcam Summary of Cloud Conditions


Webcam summary not available for this day

Wind rose