Daily Report for 21st October 2017

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Measure Value (anomaly) Time Month cumul. Record High Record Low
Minimum Temperature 12.3 °C (+4.1) 22:29 10.9 °C (+1.9) 12.9 °C (+4.7), 2020 0.0 °C (-8.2), 2010
Maximum Temperature 15.1 °C (+0.9) 13:14 16.7 °C (+1.3) 18.1 °C (+3.9), 2022 10.7 °C (-3.5), 2021
Mean Temperature 13.5 °C (+2.5) 13.9 °C (+1.6) 15.4 °C, 2013 6.3 °C, 2010
Minimum Humidity 65% 15:36 68% 94%, 2012 47%, 2014
Maximum Humidity 95% 02:59 92% 99%, 2022 79%, 2011
Mean Humidity 81% 81% 96%, 2012 69%, 2011
Minimum Pressure 1001 hPa 16:31 1013 hPa 1026 hPa, 2018 979 hPa, 2023
Maximum Pressure 1005 hPa 00:00 1019 hPa 1031 hPa, 2018 996 hPa, 2009
Mean Pressure 1002 hPa 1016 hPa 1029 hPa, 2018 986 hPa, 2023
Mean Wind Speed 10.2 mph (+6.1) 5.9 mph (+1.8) 10.2 mph, 2017 2.5 mph, 2018
Maximum Wind Speed 23.8 mph 15:29 14.7 mph 23.8 mph, 2017 9.7 mph, 2015
Maximum Gust 38.0 mph 16:26 23.4 mph 38.0 mph, 2017 14.3 mph, 2015
Mean Wind Direction SSW
Rainfall 3.3 mm 18.7 mm (42%) 17.0 mm, 2020
Maximum Hourly Rain 1.1 mm 09:09 4.5 mm, 2023
Maximum 10-min Rain 0.9 mm 09:03 1.5 mm, 2023
Maximum Rain Rate 13 mm/h 09:00 24 mm/h, 2014
Minimum Dew Point 8.0 °C 16:57 8.3 °C 12.1 °C, 2013 -3.4 °C, 2010
Maximum Dew Point 13.5 °C 03:28 13.0 °C 15.2 °C, 2013 5.1 °C, 2010
Mean Dew Point 10.2 °C 10.7 °C 13.6 °C, 2013 1.6 °C, 2010
Measure Value Time Month cumul. Record High Record Low
Night Minimum (21-09) * 12.4 °C * 06:49 11.4 °C 14.0 °C, 2020 -0.4 °C, 2010
Day Maximum (09-21) 15.1 °C 13:14 16.7 °C 18.1 °C, 2022 10.7 °C, 2021
Max 10m Temp Rise 0.4 °C 09:57 0.4 °C 0.7 °C, 2010 0.2 °C, 2015
Max 1hr Temp Rise 1.5 °C 10:32 1.5 °C 3.3 °C, 2010 0.6 °C, 2015
Max 1hr Hum Rise 10% 01:13 6% 17%, 2014 2%, 2012
Max 10m Temp Fall 0.4 °C 00:45 0.4 °C 1.6 °C, 2014 0.1 °C, 2013
Max 1hr Temp Fall 0.9 °C 06:43 1.2 °C 2.7 °C, 2014 0.2 °C, 2015
Max 1hr Hum Fall 11% 10:38 8% 18%, 2014 1%, 2015
Max 10m Wind Speed 17.3 mph 14:21 11.1 mph 17.3 mph, 2017 4.5 mph, 2009
Minimum Feels-like 13.0 °C 20:59 11.2 °C 15.2 °C, 2013 -2.9 °C, 2010
Maximum Feels-like 17.4 °C 03:26 19.3 °C 21.7 °C, 2022 11.2 °C, 2021
Mean Feels-like 14.9 °C 15.6 °C 18.5 °C, 2013 5.2 °C, 2010
Air-frost Hrs 0 hrs 0 hrs 0.0 hrs, 2010 0 hrs, 2009
Measure Value (anomaly) Month cumul. Record High Record Low
Temperature Range 2.8 °C (-3.2) 5.8 °C (-0.5) 11.4 °C (+5.4), 2010 2.4 °C (-3.6), 2019
Humidity Range 30% 24% 46%, 2014 4%, 2012
Pressure Range 4 hPa 7 hPa 29 hPa, 2021 2 hPa, 2009
Measure Value [% of max] Month cumul. Record High Record Low
Sun Hours 5.5 [59%]62 hrs (76%) [30%] 9.3 [100%], 2018 0 [0%], 2009
Wet Hours 3
[Mean rain rate: 1.1 mm/h]		20 hrs (59%) [3.9%] 12, 2020 0, 2010
Cloud Cover Partly Cloudy with periods of Mostly Sunny
Events None
Comments am Showers
Extra Comments
Issues None known
Observer Absent? Yes - observations may be unreliable
Pond Temperature @ Hampstead Heath 0.0 °C
Notes
Detailed daily weather report for Hampstead nw3 in London on 21st October 2017.
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

day graph

Webcam Summary of Cloud Conditions

daycamsumLarge resolution version

Wind rose