Daily Report for 12th December 2016

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Measure Value (anomaly) Time Month cumul. Record High Record Low
Minimum Temperature 4.2 °C (+0.6) 05:09 5.4 °C (+1.6) 10.5 °C (+6.9), 2021 -4.7 °C (-8.3), 2012
Maximum Temperature 11.6 °C (+3.4) 22:07 10.5 °C (+1.9) 13.2 °C (+5.0), 2015 0.8 °C (-7.4), 2022
Mean Temperature 8.3 °C (+2.0) 7.9 °C (+1.7) 11.7 °C, 2021 -1.1 °C, 2012
Minimum Humidity 78% 12:24 71% 97%, 2013 63%, 2018
Maximum Humidity 90% 18:52 80% 98%, 2009 88%, 2015
Mean Humidity 81% 76% 98%, 2013 79%, 2018
Minimum Pressure 1020 hPa 18:09 1023 hPa 1029 hPa, 2024 972 hPa, 2019
Maximum Pressure 1026 hPa 00:26 1026 hPa 1034 hPa, 2024 1004 hPa, 2019
Mean Pressure 1023 hPa 1025 hPa 1032 hPa, 2024 989 hPa, 2019
Mean Wind Speed 2.3 mph (-2.8) 3.3 mph (-1.8) 7.8 mph, 2015 1.1 mph, 2012
Maximum Wind Speed 6.8 mph 19:53 9.8 mph 22.5 mph, 2011 6.8 mph, 2016
Maximum Gust 10.5 mph 15:32 14.6 mph 40.9 mph, 2011 9.7 mph, 2012
Mean Wind Direction SSW
Rainfall 0.8 mm 7.8 mm (35%) 11.0 mm, 2023
Maximum Hourly Rain 0.6 mm 16:28 3.0 mm, 2014
Maximum 10-min Rain 0.2 mm 16:28 1.1 mm, 2014
Maximum Rain Rate 0.5 mm/h 15:58 18 mm/h, 2014
Minimum Dew Point 0.7 °C 05:09 1.4 °C 8.8 °C, 2021 -5.1 °C, 2012
Maximum Dew Point 9.6 °C 19:03 6.3 °C 11.3 °C, 2021 0.1 °C, 2022
Mean Dew Point 5.2 °C 4.0 °C 10.2 °C, 2021 -2.2 °C, 2012
Measure Value Time Month cumul. Record High Record Low
Night Minimum (21-09) 4.2 °C 05:09 5.8 °C 9.7 °C, 2021 -4.7 °C, 2012
Day Maximum (09-21) * 11.5 °C * 20:34 10.4 °C 13.2 °C, 2015 0.8 °C, 2022
Max 10m Temp Rise 0.3 °C 12:19 0.3 °C 0.6 °C, 2013 0.2 °C, 2014
Max 1hr Temp Rise 0.9 °C 12:19 1.2 °C 2.2 °C, 2013 0.4 °C, 2018
Max 1hr Hum Rise 4% 12:52 3% 9%, 2014 0%, 2013
Max 10m Temp Fall 0.4 °C 12:48 0.3 °C 0.5 °C, 2014 0.1 °C, 2015
Max 1hr Temp Fall 1.2 °C 04:26 0.9 °C 1.5 °C, 2010 0.2 °C, 2015
Max 1hr Hum Fall 3% 19:55 4% 9%, 2014 1%, 2013
Max 10m Wind Speed 5.5 mph 19:54 7.4 mph 15.4 mph, 2011 5.5 mph, 2012
Minimum Feels-like 3.5 °C 05:52 3.6 °C 11.6 °C, 2021 -7.9 °C, 2017
Maximum Feels-like 12.0 °C 22:17 10.7 °C 14.8 °C, 2021 0.7 °C, 2022
Mean Feels-like 8.0 °C 7.6 °C 13.1 °C, 2021 -2.2 °C, 2017
Air-frost Hrs 0 hrs 0.3 hrs 15 hrs, 2022 0 hrs, 2009
Measure Value (anomaly) Month cumul. Record High Record Low
Temperature Range 7.4 °C (+2.9) 5.1 °C (+0.3) 8.6 °C (+4.1), 2013 1.8 °C (-2.7), 2022
Humidity Range 12% 10% 28%, 2018 1%, 2013
Pressure Range 6 hPa 4 hPa 32 hPa, 2019 3 hPa, 2010
Measure Value [% of max] Month cumul. Record High Record Low
Sun Hours 0 [0%]27 hrs (106%) [31%] 6.3 [89%], 2017 0 [0%], 2014
Wet Hours 1
[Mean rain rate: 0.8 mm/h]		10 hrs (42%) [3.5%] 11, 2023 0, 2009
Cloud Cover Overcast
Events None
Comments Showers
Extra Comments
Issues 10-19 T/H data loss (12-19 casa-subbed)
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 12th December 2016.
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