Daily Report for 19th December 2012

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Measure Value (anomaly) Time Month cumul. Record High Record Low
Minimum Temperature 1.6 °C (-1.8) 00:20 1.0 °C (-2.7) 13.2 °C (+9.8), 2015 -5.3 °C (-8.7), 2010
Maximum Temperature 7.5 °C (-0.2) 13:08 6.2 °C (-2.1) 16.0 °C (+8.3), 2015 0.1 °C (-7.6), 2010
Mean Temperature 5.0 °C (-1.0) 3.8 °C (-2.4) 14.8 °C, 2015 -2.6 °C, 2010
Minimum Humidity 84% 13:38 74% 93%, 2021 57%, 2014
Maximum Humidity 98% 07:28 94% 98%, 2012 82%, 2016
Mean Humidity 94% 86% 96%, 2021 76%, 2014
Minimum Pressure 1010 hPa 22:50 1004 hPa 1034 hPa, 2017 988 hPa, 2019
Maximum Pressure 1020 hPa 00:54 1015 hPa 1039 hPa, 2021 1000 hPa, 2010
Mean Pressure 1016 hPa 1010 hPa 1035 hPa, 2021 996 hPa, 2010
Mean Wind Speed 4.8 mph (-0.3) 4.5 mph (-0.6) 11.9 mph, 2022 0.5 mph, 2016
Maximum Wind Speed 15.4 mph 19:58 12.0 mph 21.7 mph, 2022 4.7 mph, 2016
Maximum Gust 22.1 mph 19:58 17.7 mph 34.6 mph, 2022 6.3 mph, 2016
Mean Wind Direction SE
Rainfall 6.0 mm 29.5 mm (84%) 11.0 mm, 2023
Maximum Hourly Rain 2.0 mm 18:08 3.7 mm, 2013
Maximum 10-min Rain 0.9 mm 17:30 2.0 mm, 2014
Maximum Rain Rate 6 mm/h 17:25 30 mm/h, 2014
Minimum Dew Point 0.7 °C 00:20 -0.9 °C 9.4 °C, 2015 -8.0 °C, 2010
Maximum Dew Point 6.4 °C 11:34 4.2 °C 13.5 °C, 2015 -1.6 °C, 2010
Mean Dew Point 4.2 °C 1.5 °C 11.2 °C, 2015 -4.4 °C, 2010
Measure Value Time Month cumul. Record High Record Low
Night Minimum (21-09) 1.6 °C 00:20 1.3 °C 12.6 °C, 2015 -4.3 °C, 2010
Day Maximum (09-21) 7.5 °C 13:08 6.2 °C 16.0 °C, 2015 0.1 °C, 2010
Max 10m Temp Rise 0.3 °C 10:05 0.3 °C 0.3 °C, 2010 0.1 °C, 2023
Max 1hr Temp Rise 1.3 °C 10:43 1.3 °C 1.4 °C, 2017 0.1 °C, 2023
Max 1hr Hum Rise 6% 18:22 5% 9%, 2013 1%, 2021
Max 10m Temp Fall 0.3 °C 00:11 0.3 °C 0.9 °C, 2013 0.2 °C, 2015
Max 1hr Temp Fall 0.6 °C 14:35 1.0 °C 2.1 °C, 2013 0.4 °C, 2016
Max 1hr Hum Fall 10% 12:35 9% 17%, 2014 2%, 2016
Max 10m Wind Speed 10.7 mph 17:11 9.0 mph 16.6 mph, 2022 2.5 mph, 2016
Minimum Feels-like -0.5 °C 03:46 -2.3 °C 14.9 °C, 2015 -9.8 °C, 2010
Maximum Feels-like 6.3 °C 13:47 5.6 °C 18.6 °C, 2015 0.0 °C, 2010
Mean Feels-like 3.1 °C 1.5 °C 16.7 °C, 2015 -5.9 °C, 2010
Air-frost Hrs 0 hrs 3 hrs 23 hrs, 2010 0 hrs, 2012
Measure Value (anomaly) Month cumul. Record High Record Low
Temperature Range 5.9 °C (+1.6) 5.3 °C (+0.7) 7.6 °C (+3.3), 2014 1.9 °C (-2.4), 2016
Humidity Range 14% 20% 34%, 2014 3%, 2016
Pressure Range 10 hPa 11 hPa 18 hPa, 2013 2 hPa, 2017
Measure Value [% of max] Month cumul. Record High Record Low
Sun Hours 0 [0%]55 hrs (138%) [41%] 6.5 [93%], 2009 0 [0%], 2010
Wet Hours 7
[Mean rain rate: 0.9 mm/h]		29 hrs (76%) [6.3%] 11, 2023 0, 2009
Cloud Cover Overcast
Events None
Comments 13-15, 17- Light Rain with breaks (17-18 Moderate)
Extra Comments
Issues some 14-17 wind data loss
Observer Absent? No
Pond Temperature (Heath) 0.0 °C
Notes
Detailed daily weather report for Hampstead nw3 in London on 19th December 2012.
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

daycamsum

Wind rose