January 2023:
January 2023 was very clearly split into two
halves. From the 1st to the 15th the weather was vey wet and mild. In the
second half it was much dryer and colder until the last week when
temperatures recovered. The consequence of this was for the monthly average
temperature of 6.3°C came out at a very modest 0.6°C above the average for
the month. Rainfall for the month, despite the dry last two weeks, on the
other hand was still high at 146.3 mm (154.5% of the 30 year average
1991-2020). It was the wettest January since 2014 and continues a slightly
rising January rainfall over the historical period starting in 1853.
There was no snowfall
in January 2023 but there were 9 consecutive days when frost was recorded.
There were 71 hours when the temperature was below 0.0°C in the month and
this is the highest in January since this data started in 2016.
It was the sunniest January since records began in 2006 with 24.8% of the
maximum. The average for January is 20.2%.
Nearly 60% of the wind direction was from a south west or west south
westerly direction despite the cold snap in the month which mainly saw calm
days.
January 11th 2023 saw a 24 hour rainfall of 43.2mm. This was the second
highest for the month. The highest was 52.0mm in January 1926 with data
starting in 1893. The lowest daily maximum temperature of 1.1°C on the 21st
was the lowest for the month since 0.2°C in January 2013 The lowest daily
mean temperature of -0.7°C also on the 21st was the lowest for January since
2010.
Autumn 2022 With
respect to the autumn season September - November it was mild and wet. The
mean temperature was 13.7°C which made 2022 the joint warmest autumn, with
2011, in 132 years. The 30 year average for the season in Bristol is 12.0°C.
With a total rainfall of 328.9mm in the autumn of 2022 it was 24th
wettest in 141 years of continuous data for city. The 30 year average for
the season is 258.8 mm so 2022 had an excess above average of 70.1mm.
Annual 2022:
In 132 complete years of Bristol's average temperatures, in 2022 it was the
warmest at 12.7°C. The previous warmest was 2014 when the average
temperature reached 12.5°C. 2022 was 1.1°C above the 30 year average
(1991-2020) of 11.6°C. August was the hottest month with an average
temperature of 20.8°C.
The annual rainfall of 798.4 mm for 2022 was 87.4% of the 30 year average
(1991-2020) for the city of 913.8 mm. The wettest month was November with
157.7 mm (157.0% above the 30 year average 1990-2020) of rainfall whilst the
driest was July with only 17.5 mm of rain. There was measurable rainfall
during the year for 4.2% of the time (371 hours). The first 9 months of 2022
produced 407.6 mm or rain whilst the last three months of the year produced
390.8 mm.
2022 was the least windy year with an average wind speed of 4.2 mph since
records began in 2005. The average for the whole period is 5.4 mph. Notable
was the increase of 'calm' days in 2022 when the wind speed is less than 0.5
mph throughout the day. The average (2005-2022) 1.4% calm days but in 2022
this was 7.1%. There were 20 days of air frost, 3 days, 1 with two
occurrences, of thunderstorms and 3 days of small hail recorded. There was 1
day of snowfall which was lying for 1 day at 09:00 GMT. It was very close to
the average for the percentage of maximum sunshine. In 2022 this was 40.7%
when the annual average is 40.2%. The maximum daily temperature of 36.9°C on
the 18th July was the highest recorded for Bristol. The lowest temperature
of 2022 at -5.8°C recorded on 15th & 16th December was the lowest of any
month since February 2012.
To
view a full report of the Bristol Annual Weather 2021 and a discussion of trends
etc click here. This is a Word created .doc document
which is produced annually for a couple of Bristol Naturalist Society
publications. Please acknowledge the source if quoting any of the contents.
Thank you.
The
2022 Annual summary is here:
http://www.bristolweather.org/weather2022annual.htm
For the full monthly summary please go here:
http://www.bristolweather.org/weather2023
January.htm
The
Meteorological site is situated in an urban housing area approximately one
mile to the south of the Centre of Bristol.
This area is in a district called Totterdown.
Statistical correlations with the Bristol
Meteorological Office site, that was
less than two miles to the North and was
situated on top of a City Centre office block, were generally good with
rainfall and barometric data particularly close.
The site of the station is approximately 34 metres above sea level with the
manual instruments mounted in a Stevenson screen. The screen is sited
centrally in a small concreted garden area. A Snowdon
rain gauge is mounted correctly in the ground but does not have the full open
space required around it. A Davis
Vantage Pro2 Plus automatic weather station (AWS) was
added in May 2005 and this is mounted 4 feet above a concrete shelter. The
wind data is gathered automatically from a Davis Vantage Pro2 Plus anemometer which is
sited 3.3 metres (10 feet) above the house top.
Manual observations are still taken at approximately 09:00 hours GMT every
day for rainfall and cloud cover. Rainfall manually recorded in the Snowdon rain gauge is entered for the previous day. The
wind data is constantly logged and automatically reset at 24:00 hours GMT
every day (in the summer BST -1 hour. The Davis rainfall tipping bucket was recalibrated in November 2005 and is now
consistently under 3% under recording (an improvement from installation in
May 2005 when 10% was more
typically the norm).
Since the arrival of the Davis
Vantage Pro2 Plus equipment in May 2005 temperatures, humidity and barometric
pressure are recorded from the new equipment. These figures will be more
accurate and will be taken at exactly 09:00 GMT (in the summer BST -1 hour)
as the data is now logged to a computer.
By default the Davis
equipment records every parameter for the 24 hour period 00:00 to 23:59 BST
or GMT. Data analysis will enable manual data extraction of temperatures and
rainfall to 09:00 GMT (adjusted in the summer). Due to the 0.2 mm (tipping
bucket) measurements of precipitation recorded by the Davis equipment the
Snowdon rain gauge will still be used due to its greater accuracy (see
above).