Daily Report for 12th July 2017

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Measure Value (anomaly) Time Month cumul. Record High Record Low
Minimum Temperature 14.2 °C (+0.1) 05:56 16.0 °C (+2.2) 18.2 °C (+4.1), 2022 8.9 °C (-5.2), 2020
Maximum Temperature 21.2 °C (-1.9) 16:01 25.7 °C (+2.9) 30.5 °C (+7.4), 2022 18.8 °C (-4.3), 2011
Mean Temperature 17.0 °C (-0.9) 20.6 °C (+2.6) 24.9 °C, 2022 14.5 °C, 2012
Minimum Humidity 45% 20:06 42% 69%, 2021 35%, 2020
Maximum Humidity 87% 03:47 78% 97%, 2009 74%, 2010
Mean Humidity 69% 59% 88%, 2021 59%, 2010
Minimum Pressure 1006 hPa 03:04 1012 hPa 1027 hPa, 2020 1005 hPa, 2012
Maximum Pressure 1023 hPa 23:53 1019 hPa 1030 hPa, 2020 1010 hPa, 2009
Mean Pressure 1015 hPa 1016 hPa 1029 hPa, 2020 1008 hPa, 2009
Mean Wind Speed 4.4 mph (+0.1) 3.4 mph (-0.9) 7.3 mph, 2023 1.1 mph, 2021
Maximum Wind Speed 13.0 mph 09:08 10.5 mph 17.3 mph, 2023 6.9 mph, 2013
Maximum Gust 17.8 mph 04:06 16.0 mph 25.0 mph, 2009 10.9 mph, 2013
Mean Wind Direction NNE
Rainfall 9.9 mm 39.6 mm (222%) 42.0 mm, 2021
Maximum Hourly Rain 3.3 mm 02:58 20.0 mm, 2021
Maximum 10-min Rain 1.3 mm 02:55 6.0 mm, 2016
Maximum Rain Rate 30 mm/h 00:10 126 mm/h, 2016
Minimum Dew Point 6.5 °C 21:25 8.9 °C 13.4 °C, 2022 6.5 °C, 2012
Maximum Dew Point 13.3 °C 01:25 14.4 °C 18.4 °C, 2022 11.7 °C, 2020
Mean Dew Point 10.8 °C 11.9 °C 16.0 °C, 2022 9.3 °C, 2020
Measure Value Time Month cumul. Record High Record Low
Night Minimum (21-09) 14.2 °C 05:56 16.0 °C 18.2 °C, 2022 8.9 °C, 2020
Day Maximum (09-21) 21.2 °C 16:01 25.7 °C 30.5 °C, 2022 18.8 °C, 2011
Max 10m Temp Rise 0.7 °C 11:16 0.7 °C 1.0 °C, 2014 0.4 °C, 2011
Max 1hr Temp Rise 1.8 °C 13:13 2.3 °C 4.2 °C, 2022 1.7 °C, 2016
Max 1hr Hum Rise 12% 22:19 9% 21%, 2012 7%, 2019
Max 10m Temp Fall 0.5 °C 19:00 0.6 °C 0.9 °C, 2016 0.4 °C, 2010
Max 1hr Temp Fall 1.8 °C 20:57 2.0 °C 3.3 °C, 2020 1.3 °C, 2023
Max 1hr Hum Fall 14% 12:58 9% 15%, 2014 7%, 2016
Max 10m Wind Speed 9.3 mph 09:12 7.9 mph 12.5 mph, 2023 5.0 mph, 2021
Minimum Feels-like 16.4 °C 05:05 17.8 °C 21.4 °C, 2022 9.0 °C, 2020
Maximum Feels-like 22.4 °C 15:41 28.3 °C 36.2 °C, 2022 19.7 °C, 2012
Mean Feels-like 18.7 °C 22.9 °C 29.6 °C, 2022 15.7 °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 7.0 °C (-2.0) 9.7 °C (+0.7) 15.7 °C (+6.7), 2020 4.5 °C (-4.5), 2011
Humidity Range 42% 36% 59%, 2020 21%, 2011
Pressure Range 17 hPa 7 hPa 17 hPa, 2017 2 hPa, 2015
Measure Value [% of max] Month cumul. Record High Record Low
Sun Hours 5.5 [37%]92 hrs (119%) [51%] 13 [87%], 2020 0.1 [1%], 2015
Wet Hours 6
[Mean rain rate: 1.7 mm/h]
14 hrs (106%) [4.9%] 8, 2012 0, 2011
Cloud Cover am: Overcast transitioned to Partly Cloudy
pm: Mostly Sunny
Events None
Comments o.night Rain
Extra Comments
Issues Rn data from N16
Observer Absent? Yes - observations may be unreliable
Pond Temperature (Heath) 0.0 °C
Notes
Detailed daily weather report for Hampstead nw3 in London on 12th July 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