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2016-07-22_15-53-56

Reigate June 2016 weather statistics

  • T average 16C
  • Tmax 25.6C
  • Tmin 8.5C
  • Total rainfall 100mm
  • Max gust 28mph
  • total sunshine 114 hours

June 2016 was wet in Surrey with over 246% of normal rainfall.  SE England as a whole received 113mm of rain, 208% of long term average.  At 118.4mm, Surrey was the wettest county in the UK regarding anomalously high precipitation. Despite this, both 1971 and 2012 were wetter months.

The rain was delivered in a number of distinct heavy showers and convective thunderstorm events, notably on 23 June when parts of South London were especially badly flooded in flash flooding during torrential rainfall of more than 50mm in one storm.

http://www.huffingtonpost.co.uk/entry/uk-weather-flood-warnings-as-torrential-rain-falls-on-london_uk_576b9225e4b0b1f1704feabb?7liv7jj9ylkz3q5mi&

The heaviest rainfall was characteristically patchy so not every part of Surrey experienced the same soaking, some parts were a lot wetter than others. For example, while Caterham received over 40mm in one thunderstorm, Reigate received only 10mm from the same storm.  In total, Reigate received 100mm of rain in June which compares with 15mm for June 2015 and 30mm for 2014.

“Surrey with 118.4mm of rain endured the worst rainfall of any county, relative to its average. The June average rainfall for Surrey between 1981 and 2010 is just 50.7mm. This month’s total was 246% of normal.” MetOffice

A thunderstorm on 23 June brought an amber warning and local flooding and lightning damage to some places in the SE. Below are some news reports from the time.

A shelf cloud was spotted over Reigate, one of the first observed over the town.

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Horsham experienced intense lightning and one bolt struck a conifer at 2am which was destroyed in a spectacular explosion.  Fortunately no one was hurt, but cars and property was damaged.

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convective June 2016 Priory Park

June started well but pressure fell from 10 June and the month remained mostly unsettled thereafter.

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Due to the unsettled conditions and rainfall and associated cloud, June was less sunny than usual, with only 114 hours of sunshine recorded in Reigate. June 2015 had 192 hours of sunshine in comparison.

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June was just about 1C above the long term 1981-2010 UK average at 13.9C.  Reigate recorded a monthly average of 16C which is considerably higher than the UK average being located in the warmer SE.

Globally June 2016 was the warmest June since records began in 1880 and was the 14th month in a row to beat global long term average temperature. The charts below show NOAA, NASA and UAH global temp anomaly maps for June. All agree that June was hot.

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With one month after another breaking heat records, 2016 is easily on target to be the hottest year on record despite a waning El Nino.

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This continues the inexorable rise in global temperature in recent years.

2016-07-20_12-20-54

2016-01-01_12-04-44

Reigate December 2015 summary statistics:

  • Tmax 15.5C
  • Tmin 1.6C
  • Average temperature 10.1C warmest on record (2014 5.3C)
  • Total rainfall 79mm
  • max gust 37mph
  • sunshine 79.8 hours

Like the rest of England and Wales, Reigate had an exceptionally warm December and the warmest on record by a huge margin.

Central England Temperature December records smashed!

2015 warmest December CET ever recorded: 9.7C
December 1934, 1974: 8.1C

This is warmer than any March CET.
Warmer than any November barring 1994
There have been 171 colder Octobers
There have been 26 warmer Aprils
There have been 34 cooler Mays

The CET mean minimum was higher than any April mean minimum ever recorded.  It was higher than the May’s CET minimum

The gap between September and December’s CET was less than 3.0C, the gap between their respective minima was just 1.1C!

The CET mean maximum was 1.8C higher than the previous record of 1974.

(source CET data from UKWW)

In Reigate the average temperature was 10.1C compared to 5.3C, 5.8C and 6C in 2014, 2013 and 2012 respectively.  Whilst our own Reigate records only go back to 2012 (neighbour stations extend this locally back further to 2009), the Central England Temperature record extends back to 1772 and, at 9.8C monthly average, December 2015 smashed all previous mean monthly temperatures by a long way. The official Central England Temperature anomaly (temperature departure from normal long term average) came out at a whopping  5.2C above average, way above previous warm Decembers of 1934 and 1974.

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The chart above shows the monthly average data in Reigate this year as an anomaly departure from the long term average for SE England – (source MetOffice Hadobs 1910-present).  It starkly shows how much warmer December was from the long term average extending back to 1910, Reigate was a full 5.6C above normal!  How much is this down to El Nino? As discussed in previous posts the El Nino ENSO Pacific warming natural cycle cannot explain all of this extraordinary warmth.  In fact, there is little established link between El Nino and UK winter weather.  This is shown in the charts below for previous mega-El Ninos in 1982 and 1997 which had markedly different impacts on our December winter weather.  So there appears to be no real solid link between El Ninos and any crazy warm winter / December weather here.

Remember that the recent Paris climate change conference has sought to set a target of limiting global temperature rise to no more than 2C temperature increase over pre-industrial levels.  Locally we can expect spikes in temperature of course but this 5C anomaly for December, and the fact that 2015 will certainly be the warmest on record globally, shows the huge challenge that lies ahead in keeping temperatures down to less than 2C globally.

It was so warm for so long that wild flowers and plants around Reigate such as daffodils, camelias, forsythia and rhododendrons came into flower as if it was Spring.  This was a lot to do with minimum temperatures being so high with no frosts recorded at all.

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Many records were broken across the UK for highest minimums overnight, which frequently stayed in double figures. Indeed, this December has had a similar mean temperature to that expected in May. Our own station recorded the highest December Tmax at 15.5C on 19 December and the highest overnight Tmin at 12.4C on 26 Dec.2016-01-01_15-28-59

Despite the record breaking deluge further North which made this the UK’s wettest December of record overall), rainfall in Reigate came out around or even a tad below average at 79mm.

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Whilst 2014 was drier still at only 49.4mm, 2013 saw 110mm.  Regionally, South East England got around the average rainfall normally expected in December.  Like November 2015, December continued the sun-less theme with only 79.8 hours of sunshine.

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Apart from the incredible and perturbing warmth (which extended to the North Pole at the end of the month courtesy of Storm Frank) December 2015 was not remarkable for much else weatherwise locally.   Unfortunately, in Cumbria, Yorkshire and North Wales, there was extensive flooding which caused much misery and disruption especially over the Christmas period.  For more on the flooding and other weather stories please check this Flipboard magazine account.

Have a Happy New Year!  Data for Reigate and 2015 has been updated in the data page. 

http://www.metoffice.gov.uk/news/releases/archive/2015/early-dec-stats?WT.mc_id=Twitter_News_Pressrelease

http://www.getreading.co.uk/news/reading-berkshire-news/december-breaks-warm-weather-records-10673765

http://www.independent.co.uk/environment/uk-weather-why-the-recent-devastating-floods-will-become-the-new-normal-a6793291.html

https://xmetman.wordpress.com/2016/01/01/phenomenal-december-of-2015/

https://wansteadmeteo.wordpress.com/2016/01/01/december-2015-exceptionally-mild/

http://www.carbonbrief.org/analysis-how-december-2015-topped-chart-as-uks-wettest-month-on-record?utm_content=bufferf8440&utm_medium=social&utm_source=twitter.com&utm_campaign=buffer

http://www.metoffice.gov.uk/news/releases/archive/2016/december-records

http://blog.metoffice.gov.uk/2015/12/31/whats-been-happening-to-our-weather/

2015-12-13_12-13-56

November 2015 statistics for Reigate, Surrey

  • Temperature average 10C
  • Tmax 16.3C
  • Tmin -2.6C
  • Rainfall 66mm
  • Max gust 40mph
  • Sunshine 69 hours

In the UK November 2015 was the third warmest on record since 1910 and averaged 10C in Reigate with Tmax 16.3C and Tmin -2.6C.  The overall CET (Central England Temp) for November came out at 9.5C, nearly 3C above the long term average.

The month started with a trough in the Atlantic and HIGH pressure to the east bringing a mild wet southerly //SW flow to our area in the south.

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November 2015 mild SW flow

Rainfall was about average for our area at a total of 66mm for the month, though this is significantly drier than the MetOffice SE data shown below which shows the SE being wetter than average as a whole.

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South East rainfall Nov 2015

A number of named MetOffice storms impacted the UK but did not significantly affect the SE.  Ex-Tropical storm Kate swept unnoticed across the South on the 14/15 Nov and brought some blustery weather to the Downs.

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Pressure and wind gusts Reigate November 2015

Temperatures took a brief dip later in the month when a short-lived Arctic plunge brought brief wet snow which fell and settled momentarily in Reigate on the morning of 21 November.

November rain was about average for Reigate, though wetter in the NW.

November was the dullest ever on record especially here in the south.

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Some other pics of Reigate during November

Here is the MetOffice summary and blog records for the month

http://www.metoffice.gov.uk/climate/uk/summaries/2015/november

http://blog.metoffice.gov.uk/2015/11/

2015-08-21_08-15-09

Reigate July 2015 statistics

  • Average temperature 17.4C
  • Tmax 35.1C
  • Tmin 7.4C
  • Total rainfall 51mm
  • Max gust 27mph
  • Sunshine  161 hours

July 2015 in Reigate started hot, reaching 35.1C on July 1st due to a Spanish Plume.  The first day of July broke the record for the hottest July day when Heathrow spiked at 36.7C as cloud cleared around the airport allowing sunshine to heat the surface through an already very warm airmass.  This caused a heat spike at Heathrow and elsewhere that allowed the MetOffice to announce 1 July 2015 as the “hottest July day since records began and the hottest day since 2003”.  This set climate / weather data skeptics in a whirl as they spotted that the nearby Kew Gardens weather station did not correlate with the same heat spike at the same time allowing them to claim it was simply due to hotter local conditions from the local airport tarmac, a change of wind direction or even heat from a passing plane.

The photos below show the locations of the Heathrow weather station adjacent to the Northern Perimeter Road west and the Kew Gardens weather station.

In response to the doubt, Mark McCarthy, a climate scientist at the metoffice, was quoted in this article explaining that the heat spike was neither due to passing aircraft, nor a change of wind direction or any micro-climatic influence from tarmac and that the temperatures from Heathrow are representative and so the record stands.  In discussion with RGSweather on twitter, Mark also explained that the last 10 years of daily Tmax observations from Kew Gardens and Heathrow differ only by <0.03C on average.  This debate was akin to the wider global warming debate where met agencies present data that is then questioned by skeptics who present data that appears to contradict the claim. In any case, July 2015 started hot!  Unfortunately, July temperatures then promptly collapsed across the UK and the CET came out around average as westerlies returned from an anomalously cold North Atlantic.  Despite a lack-lustre July in the UK, globally, July turned out as the hottest month ever recorded.

Reigate and the SE had an average month being just nearer the European heatwave that dominated July.  Overall the monthly temperature came out a tad below the CET long term average, continuing a run of 3 cool months.  Further north and west July became a decidedly cool wash-out, especially in Scotland where snowfall occurred over some mountains.  Night time minimums were cooler than usual and some records were broken for lowest ever July night time minima.  In Reigate we recorded a Tmin of just 7.4C at the end of the month.

Here are metoffice anomaly charts showing how Reigate and the SE stayed warmer and drier than elsewhere.

SE rainfall overall came out above average mainly due to thunderstorms delivering locally heavy precipitation.  Reigate at 51mm came out nearer average because most heavy rain missed us. Although not local to our area, a thunderstorm over the Brecon Beacons in early July killed two people on top of Pen Y Fan and Cribyn.  The photo below shows this thunderstorm.

Globally, NOAA and JMA (Japanese met agency) reported that July 2015 was the hottest month ever recorded.

More from the metoffice on JUly 2015 here: http://www.metoffice.gov.uk/climate/uk/summaries/2015/july

2015-07-09_11-50-48

June 2015 Reigate summary

June in Reigate, Surrey continued the Summer 2015 theme of mostly cool, dry and sunny but with an unsettled start and THREE attempts at continental heat from Spanish Plumes in one month. (please note that the chart above hugely exaggerates the rainfall.. check the rain scale in mm.  I have yet to fix down the scales month on month!). 

  • Average Temperature  15.7C
  • Tmax 30.6C (25.6)
  • Tmin 5.5C (6.2)
  • Total rainfall 15mm (30)
  • sunshine 192 hours (175)
  • max gust 28mph

(Figures in brackets are from June 2014)

The month started unsettled with a deep low pressure 976mb crossing Scotland from a very much cooler-than-usual North Atlantic bringing brisk winds for the time of year and comparatively cool temperatures.  Another Atlantic LOW crossed Scotland through the first week 991mb (see satpic).

A weak first attempt at a Spanish Plume 5-6 June developed ahead of an Atlantic cold front and gave some limited thundery activity early morning on 5 June, these cells went on to become more significant further north east over E Anglia.

Pressure rose thereafter as an anticyclone built firmly over the UK.   This HIGH eventually slipped north and a heat LOW from Iberia brought the threat of a second Spanish Plume around 12-13 June.  This misfired and caused little convective activity over Reigate at least.  This turned out to be a significant mis-fire for convective forecasters, despite some limited activity here and there the overall level of activity was low and certainly nothing occured over Reigate except very late in the day when some congestus puffed up.

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Spanish Plume mis-fired 12 June 2015

High pressure built again with weak fronts skirting across the SE bringing some pleasant mid-level and upper level cloud, nice sunrise and sunsets and some good atmospheric optical phenomenon at times.

Towards the end of June a third attempt at a Spanish Plume yielded more heat and more purposeful thundery activity that eventually spilled over into decent thunderstorms into the start of July.  This was a modified Spanish Plume and more details can be found on the post written up here and here.

The end of June 2015 heat spike produced some 30C+ temperatures and in Reigate 30.6C was recorded on 30 June.  Overall the month was sunny but a shade cooler than average according to the CET central england temperature record.

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The UK anomaly charts reflect the overall dry pattern with notably little rainfall for the month.  In Reigate the total rainfall measured was 15mm.

Although this June was not consistently hot tp push up the CET (central england temp), we did nevertheless have episodes of unusual heat, especially at the end of the month with the end of June / early July heat spike.  This heat wave was more severe and prolonged in Europe.  A “cause” of the Euro heat wave, with significant heat in Spain and Portugal, was an OMEGA BLOCK or “shruggie”  that built through June and lasted into early July.  This Omega Block pattern may also be linked to rapid melting of the Greenland icecap that has been recently reported as heat builds there under high surface pressure.

A weather pattern that resembles an atmospheric version of the shruggie — ¯\_(ツ)_/¯ — is directing furnace-like heat toward Spain, France and England on Wednesday, with high temperatures near 40 degrees Celsius, or 104 degrees Fahrenheit, as far north as Paris.

The heat wave is also affecting southern parts of England, with temperatures in the upper 30s Celsius, or mid-to-high 90s Fahrenheit. Those temperatures on Wednesday were the warmest recorded in the UK in at least nine years, according to the UK Met Office.

Andrew Freeman, Mashable 1 July 2015

heat wave / mini!

heat wave / mini! south east England Surrey

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

http://www.climatecentral.org/news/maps-greenlands-melt-season-19196

http://mashable.com/2015/07/01/england-france-spain-heat-wave/

2015-06-07_11-16-50

May weather summary Reigate Surrey SE England

May 2015 summary data for Reigate

  • Average temp 12.1C
  • Tmax 20.7C
  • Tmin 4.1C
  • Total rainfall 62.7mm (CoCoRahs manual rain guage)
  • average wind speed 21mph
  • Max gust 38mph
  • total sunshine 161.2 hours

At 12C the May average temperature in Reigate was a tad cooler than long term average, as it was for the whole of the UK at a mere 9.6C, (0.4C below the long term average for the SE).  May was the first month since August 2014 to be below CET long term average. The chart below shows the mean monthly 500mb geopotential height for May and shows a big LOW to the NW of the UK.  This pattern would generally cause a cooler than average W/NW flow across the UK, especially the northern part of the country.

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May mean monthly 500mb geopotential height reanalysis

The culprit causing the slightly cool / unsettled May was a LOW pressure in the Atlantic to the N/NW of the UK that caused a NW airflow which also reduced sunshine hours below average, at 161 hours.

May rainfall in Reigate was 53mm.  Frontal rainfall from occluding Atlantic LOWS brought rain early in the month when it was quite windy too, with max gusts over 35mph on May 6-7.  Sunshine totals were low during the first half of the month but picked up mid month and later.

A trough disruption May 13-15 caused a particularly wet 24 hours 13-14 May.  Trough disruptions are notorious for causing unpredictable weather events, including causing poor model forecasts for rainfall.   The charts below show the trough disruption progress.

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trough disruption May 14 2015

The satellite picture below shows the LOW resulting from the disrupted trough and the band of cloud associated with the fronts.  In Reigate this single event caused the highest daily rainfall total for May, at over 15mm (CoCoRahs manual rain gauge).

occluding LOW May 2015

occluding LOW from trough disruption 14 May 2015

A thundery event occurred on 19 May and brought heavy showers across the SE.  Here is the synoptic chart for that occasion.

Some impressive mammatus clouds were spotted locally as the cumulonimbus clouds moved away.

More details here from MetOffice

http://www.metoffice.gov.uk/climate/uk/summaries/2015/may

2015-04-07_11-05-58

March 2015 Reigate summary

Reigate March 2015 weather summary

  • Average Temperature 6.9C
  • Tmax 14.4C
  • Tmin -1.9C
  • total rainfall 23.8mm
  • max wind gust 46mph
  • sunshine 143.2 hours

Anticyclonic conditions controlled a good chunk of March bringing a lot of dry weather to Reigate.  Total Reigate March rainfall of 23.8mm is around half of that expected from the long term average for March recorded since 1873.  Whilst March rainfall this year was low it was not outside the “normal range” with mean monthly rainfall for March in South East England being 49.8mm and the mode (most frequently occurring) at a relatively dry 38.7mm.  March 2015 turns out to be the 36th driest year since 1873, the lowest being 1929 with a paltry 2mm of rainfall.  So March 2015 was dry but not super-dry!

With high pressure around March was sunny and not terribly windy, especially through the middle month.  Mid-Month the temperature dipped notably (see top chart) as a slack easterly set up with the high moving over Scandinavia.  It was not a beast from the east because the continent was warm and there was no really cold air available.  The slack conditions finished at the end of March, however, as a significant NW gale blew across the UK.  This broke our daily wind run record at 305.4 miles.  Wind run is the “fetch” or distance that the wind has travelled passing a point during the day.  Imagine a balloon drifting in the wind during the day… how far would it travel? This is the wind run.  The NW wind also turned lorries over on motorways further north, gusting over 70mph in places.  In Reigate the max gust was 46mph, pretty strong but with no leaves on the trees it did not cause damage.

143.2 hours of sunshine in Reigate exceeded the long term average.

March will be remembered for the “deep partial” solar eclipse that crossed much of the UK on 20 March.  Sadly for us in Reigate and much of the SE we saw nothing of it except a gathering gloom and slight dip in temperature.  More on our eclipse observations here: https://rgsweather.com/2015/03/21/reigate-some-eclipse-effects-on-weather/

2015 overall is above the long term CET average but not by much. Nevertheless, as a moderate El Nino is set to start properly this summer it is likely that 2015 will be break more temperature records globally as a hot year overall for the planet.

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All our weather data can be downloaded from the data page here.

MetOffice March summary 

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

http://www.metoffice.gov.uk/climate/uk/summaries/2015/march

2015-03-12_21-10-33

February 2015 Reigate weather summary

 

Weather statistics summary for Reigate during February 2015

Average temperature 3.9C (UK 3.5)

Tmax 10.8C 25/02

Tmin -3C 22/02

Total precipitation 59mm

max wind gust 32mph 06/02

February was around the long term average at 4C in Reigate.  The CET stood February at just 0.3C above the long term average.

After an intially cold start to the month the temperature rose.

Overall February came out around average temperature but note the much warmer continent.

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A notable cirrostratus halo occured around moon on 02 Feb and this accompanied by some brief excitement over a snow band moving south down the eastern side of the country.

This band delivered an insignificant snow flurry on 03 Feb, overnight, with  a cm or so of briefly lying snow that melted rapidly during the morning.

Models threatened easterly winds on occasion but this didn’t arise.  In any case Europe and the continent experienced a warmer than average month so the deep continental cold was not available.  In fact after another brief flirt with snow at the beginning of the month, the temperature climbed through the middle of the month with westerly influences with temperatures exceeding 10C overnight on occasions.

Rainfall 58mm was just a little below average and sunshine hours, at 90 hours, was about average.

 

 

 

MetOffice February summary

http://www.metoffice.gov.uk/climate/uk/summaries/2015/february

 

2014-12-04_22-21-24

November 2014 in Reigate weather summary

Average temp 8.9C

Tmax 17.2C

Tmin  -0.5C

Total precipitation 135mm

Max gust 29mph (av wind speed 16mph)

Sunshine 87.5 hours

November weather in Reigate and the SE was rather dull and uneventful in Reigate but the meteorology going on more widely was fantastically interesting!

November was considerably warmer than average.  In the UK November turned out a whopping 2C warmer than the long term CET record.  In addition some areas in the south recorded 200% more rainfall than average.

Our anomalously warm and wet November was due to our weather being dominated by warm moist southerly winds as a trough sat in the Atlantic and a fairly strong blocking high dominated Russia and occasionally Scandinavia.  The northern hemisphere flow encouraged blocking further east and a trough to the west of the UK.

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The blocking high pushed LOW pressure in the Med that fed warm moist winds up to the UK (warm air advection).  Occasional Atlantic fronts caused heavy rain when cooler air on cold fronts advected in from the west to meet this moist flow.  Heavy November rain in the south was caused by this process.  Nevertheless, the usual scaremongering forecasts in the press failed to materialise.

A split jetstream assisted the warm moist feed across much of Europe and led to torrential rain and flooding along south facing coasts in Italy and S France.  To a lesser extent this also occurred in the UK with highest rainfall anomalies found in the south and SE.

Globally November was one of the warmest on record too.  However, the US and Canada recorded one of the earliest coldest and snowiest Novembers on record. The upper air patterns plunged cold Arctic air into North America and, when this frigid polar air crossed the warm Great Lakes, it produced tremendous falls of Lake Effect snow over northern New York State, especially around Buffalo.

Autumn for the UK as a whole was the third warmest in the record going back to 1910.  Autumnal rainfall was just a tad below average because September was a very dry month.  October and November were well above average for rainfall.  The SE came out average or just above average for rain for the whole of the Autumn.

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

Globally November’s warmth and climate extremes caused the climate change debate to reignite.  The graphs below speak for themselves.  Our November was dominated by our first HIGH ALTITUDE BALLOON launch. The experience of launching our first exploration into near space brought it home to us how thin our atmosphere is, how quickly it is to escape from and thus how fragile it is.  We live perilously close to utterly hostile environments… the views of Earth brought back from our stratospheric balloon were both sensational but somehow frightening in the context of rapid climate change on the only earth we have.

 

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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