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2016-02-21_10-45-50

Reigate, Surrey January 2016 summary weather statistics

  • Tmax 12.8C
  • Tmin -5.1C
  • T av 5.2C
  • Total rain 137.2mm
  • sunshine hours 94.1 hours
  • mean pressure  1009mb
  • max gust 35mph

January 2016 was a modestly unsettled month in Reigate with frequent wet days (21 in total with >1mm) and total rainfall amounting to 137.2 mm, this was some 160% of normal expected rainfall totals for the SE as a whole for January.  This caused some surface water flooding and soggy fields but, whilst a few flood alerts were issued, the River Mole behaved itself as no one rainfall event occurred with sufficient intensity to cause significant flooding problems in the Mole catchment.

In comparison with recent years, January 2016 turned out moderately wet sitting between the very wet January 2014 183 mm and the drier Jan 2015 69mm.  Of note locally was a spectacular display of mammatus cloud on 10 January as a squall line brought a thundery trough that passed over the area bringing some hail and cumulonimbus cloud.

It was a mild month with average temps 5.2C, Tmax 12.8C and only 7 days with minimum temperatures dipping to or below freezing. The highest January max temp ever recorded occurred in N Ireland. Whilst no weather record was broken in Reigate it was still a mild month with about average sunshine.

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sunshine Reigate January 2016

At 5.4C the CET temperature for the UK was 1.6C above the long term average. At 1.13C the global average January temperature turned out to be another record breaking warm month.

Returning to local events, one brief marginal wet snowfall event occurred in Reigate and Surrey overnight 16-17 January.

Snow lay during the morning of 17 January and was just sufficient to allow families to enjoy sledging and snowman building in Reigate and Priory Park for a few hours before it all melted by midday.

 

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The mean 500mb pressure anomaly pattern for January shows the UK in a mostly stormy Atlantic regime with storms rattling through especially the NW bringing high rainfall totals there. Storm Gertrude at the end of the month did not impact the sheltered SE much. As usual the SE was relatively protected sitting nearer the higher pressure over S Europe.

 

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August 2014 weather stats for Reigate, Surrey.

Tmax 27.2c (33.5c 2013)

Tmin 5.6c (9.7c 2013)

Average temp 16c (17.4c 2013)

Total rainfall (CoCoRahs) 84.4mm (37.6mm 2013)

Max gust 36 mph (Bertha 11 Aug)

GLOBALLY, August 2014 was the warmest on record (NASA, see below).  In contrast, August 2014 for the UK was the COOLEST August for 21 years since 1993 and rainfall was 156% above long term average in some places, including parts of the SE. In Reigate the average temp was 16C compared to 17.4c in 2013.  It was also wetter than usual, for example, twice as much rain fell Aug 2014 than in Aug 2013.  This ended a run of much warmer than average months throughout 2014.  The CET (Central England Temperature) is still seeing 2014 as one of the all-time warmest years even with a cooler August.

Arguably Ex-Hurricane Bertha “destroyed” the balmy UK summer of 2014.  She emerged out of the Tropical Atlantic early in the month and took aim at the UK.  Despite weakening extra-tropical storm Bertha still dragged some cool polar air into the UK and Europe behind her.

Bertha brought little direct disruption to Reigate and the SE but an impressive squall line moved across our region during the 10 Aug.  There was no especially extreme weather associated with the squall line (regrettably for weather folk!) but the cloud-scapes were magnificent as the squall moved away further to the East. Bertha did bring some unseasonably gusty weather and 36mph was recorded at our weather station on 11 August.  Winds in excess of 40mph were recorded locally higher up.

http://www.metoffice.gov.uk/climate/uk/summaries/2014/august

http://www.metoffice.gov.uk/climate/uk/summaries/2014/summer

Interestingly, NASA have just recorded August 2014 globally as the warmest ever August on record.  This shows how discrete locations on a regional scale can buck the global trend… obviously some places have warmer and colder weather than the global average and some of these anomalies could be potentially record breaking despite being the opposite extreme of the global mean.

http://www.climatecentral.org/news/nasa-globe-warmest-august-18031

 

 

April 2014: quick monthly weather summary from our weather station in Reigate, Surrey, UK.

Another relatively dry month with 43.6mm of rain falling on Reigate, about the same as April 2013. Please note that we are still calibrating the automatic tipping bucket rain gauge which is possibly under-reading by around 10%.  Calibration is a tricky affair and we want to get it right.  We are supplementing all data by using monthly totals using our CoCoRahs manual rain gauge which is, by default, a more accurate measure of total rainfall. Raw data is available on our data page here.

There were no dramatic warm-ups or cool-downs in temperature during the month.  April 2013 saw a fairly significant warm-up from mid-month but April 2014  flat-lined with no especially warm or cold temps.  It was noticeable that air temps never dipped below freezing.  This allowed the average monthly temp to climb higher than April 2013 overall, despite a lower Tmax.

Tmax 20.4c

Tmin 1.8c

Average temp 11.2c

Total rain 43.6mm (CoCorahs)

Sunshine 138.7 hours

A high pressure dominated the South of England for the middle of the month and reduced rainfall totals.  Later in the month April showers delivered moderate rainfall totals.  There were no significant thundery episodes.

April is the month when many trees come into leaf in the UK. Below are the school lime trees in the playground taken at either end of the month.

April is also a month of lengthening days and misty mornings with heat building at the surface triggering fluffy cumulus clouds in the afternoon.  Some of these produce enough instability to produce “April showers” in cool maritime airstreams with warming at the surface.

Away from the UK, the US experienced a significant tornado outbreak at the end of April when an active cold front swept clean across the entire country and triggered 133 identified tornadoes in the Mid-West / tornado alley and at least 40 deaths.  The Mayflower tornado (EF4) on 27 April in Mississippi tore through the state leaving a 41 mile trail of destruction and 16 deaths.  Tornado damage cost over US $1 billion. http://www.weather.com/news/tornado-central/tornado-scars-april-outbreak-20140507

Excellent article here on the US tornado outbreak April 2014.

In stark contrast, but related to extreme weather elsewhere, the drought in the SW of the USA continued through the month.

Other weather news includes a potentially mega outbreak of the El Nino this year.  The El Nino is a warming of the eastern Pacific Ocean waters.  This huge ocean warming is a major fly-wheel of global climate and the ENSO is a significant gear change that impacts weather systems globally.  The warming is natural (nothing to do with AGW) but has major impacts on weather extremes around the world and could, potentially, make 2014/2015 the warmest year ever. More detail here on El Nino from the great weather guru Gav at http://youtu.be/VJXpvv0P2pw

The map below shows the usual weather relationships expected during the course of a major El Nino event (ENSO).  Note that the UK and Europe does not experience a known / correlated weather impact: i.e. an El Nino does not have a regular impact on our weather.  However, this does not mean we will not experience some impacts from this major global weather gear change. All things considered, we are lucky in the UK to have less severe weather than many countries around the world, albeit this can be a little frustrating for weather enthusiasts who like a bit of exciting non-injurious weather occasionally!

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