Archives For December 2014

Whilst this storm was uneventful for most in the UK the LOW is forecast to bring extreme cold to parts of Europe.  Here’s the story… see below for “in the event” 

Update Fri 8am! MetOffice chart brings LOW further South… this would bring in colder air more quickly for SE on Sat am possibly interacting with the frontal rain and turning it to snow for a short period, check weather warnings before travelling, especially north through the Midlands and N England and Wales tonight.

Quick update on weather prospects for Reigate and SE Boxing Day night and into Saturday 27 Dec.

The low pressure storm arriving Boxing Day afternoon is set to bring chilly conditions, lots of rain and some snow, but for who and when?  The LOW pressure is set to track overnight ESE through Wales, across the Midlands and exit through the Thames Estuary sometime in the early hours on Saturday. Strong winds are likely during this time, initially W/SW winds for the SE and Reigate building Friday pm/ evening and then veering to brisk cold winds NW/N winds by Saturday morning. Winds could reach 30-40 mph in places and more on coasts possible. Wind chill temperatures overnight will be cold, down to -6C in places. There will also be a lot of rain overnight: possibly 10-20mm in places. It is of course the snow that people are interested in.  Whilst snow is likely on the northern side of this low across parts of Wales, Midlands and N England, parts of East Anglia, for us in the SE on the milder south side of the low the snow is initially unlikely and much more marginal and more difficult to forecast.

A bit cheeky but couldn’t resist this apt tweet from WindyWilson in Scotland!

Overnight snow is unlikely for much of the SE because for much of the night we will sit in the warm flow of air to the south of the low centre.  Rain is forecast to arrive sometime mid-late afternoon. Friday will then actually warm up to possibly 6C in the evening in an occluding low as the warm front arrives.  This is called warm air advection and is what drives the lower pressure down as air rises.  It is also likely to keep any precipitation as rain for most of the night.  Overnight this warm air will be forced aloft by the chasing cold polar air sweeping down from the north, this can be seen on upper air charts below.

The charts below show snow fall is only likely on the very back edge of the system as the low pressure slips away across the Channel and drags in the coldest air from the N / NE in its wake. It is only at that point , from early on Saturday am, that the Downs and Reigate and the SE might get some snow but, even then, it is only 50% chance (see skew-t below).

On the atmospheric cross section (skew t) below for Heathrow the warm air can be seen on the 21:00hrs GMT chart as a slight bulge with increased height.  This is an isothermal layer which shows warm air is in the system at this point and likely to melt precipitation starting as snow higher up.  The skew-t diagram on the right is for some hours later at 03:00hrs GMT when temperatures can be seen to have fallen at the surface, winds veered to a cool Northerly direction after the cold front has passed through.  At this time a rough calculation of Dew Point + Temperature yields 3.3, which would give a 50% chance of snow at this location.

 

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Snow might also fall as heavy rain drags colder freezing air from above to the surface. Evaporative cooling, however, is unlikely as a snow making process because it requires less windy conditions.  By Saturday morning the polar Northerly air has arrived and this has dew points low enough for any showers possibly pushing in on the NE breeze to fall as snow at any time during the next 48 hours or so.  So… snow is unlikely for Reigate first thing overnight Boxing Day, there is a 50% chance of snow for the second half of the night, especially over high ground like the North Downs and especially if the rain is heavy enough.  Finally, as dawn breaks on Saturday any rogue showers penetrating our area could fall as snow in the frigid air.

This system is set to bring in a cold weekend and early next week a cool high pressure will keep things dry and frosty.  After New Year things look to be warming up and turning more Atlantic driven on the latest charts as winds bring rain back from west.

 

Why is forecasting snow so tricky?  http://blogs.channel4.com/liam-dutton-on-weather/snow-challenging-forecast-uk/2568

In the event:

Snow fell as forecast by MetOffice across Northern England / Midlands and caused some traffic problems and flight cancellations out of regional airports Manchester and Liverpool.  Snow accumulation up to 10cm was reported and some low wind chill.  The snow zone was a discrete area and to the south the warm sector kept everywhere south of the Midlands free from snow and, as expected, mild throughout (8C) until the polar air arrived behind the LOW. Some sleety showers and possible snow flurries came and went uneventfully across the SE and especially Kent but no accumulations were reported.

The LOW had much more wintry impact into Europe: with Netherlands through to the Alps receiving significant snowfall.  The LOW is forecast to continue SE into SE Europe and drag in some freezing polar continental air into the Balkans, Greece and even reaching as far as the North African coast.  Temperatures as low as -20C are expected across Serbia.  SNOW fell in Algeria.

Update #2 25/12/14: update: cold weather arriving after this LOW, heavy rain overnight Fri-Sat; snow marginal for SE early Sat am, more likely for Midlands and EA, cold weather arrives in lee of this system.  MetOffice warnings updated:

Update #1 25/12/14 latest MetOffice chart lifts pressure and pushes track further south, with low moving SE across our area.  This reduces wind speed, still brings in colder air flow though with risk of snow increased for back northern edge of the system with NE winds. For SE possible sleet/snow on Downs early Sat am. Evaporative cooling could yield more snow for SE if rain sufficiently heavy (drags down cold uppers). Gale risk gone but replaced by some heavy rain, marginal snow risk and retaining the cold easterlies in the aftermath on Saturday with pressure building to dry bright frosty conditions.

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After a pleasantly cool bright and dry Christmas Day, an interesting depression due on Friday and through Saturday is likely to usher in a period of colder weather for the UK and SE in particular. The situation is a little uncertain still but the run of warm mild gloomy temperatures lately this December, already pushed aside gently by a weak cold front passing south through the country today, are likely to be pushed further down into some “proper”cold after the storm passes through by Sunday. This storm, forms in the Atlantic along the polar front and quickly races east towards the UK on Boxing Day Friday.  Storms tend not to deepen much if they move fast, which this one does at first: crossing half the Atlantic in a matter of 24 hours. The storm is mixing some airmasses with contrasting temperatures: cold polar air in the north is about to get up close and personal to mild warm Tropical air from the south west.  They are due to meet in the LOW pressure over the UK soon, so expect some interesting weather!  You can spot the impact of the storm on the upper air temperature chart below but also see the steeper drop to colder conditions thereafter.

GEFS shows cooler days ahead

GEFS shows cooler days ahead

The ECM charts below show upper air temperatures at around 1500m. These “850hPa” charts are commonly used as guides to airmasses because air at 1500m (850hPa pressure level) is not affected by changes day and night or surface characteristics, it is therefore a good guide to true airmass characteristics.  Note the really cold airmass to the north meeting comparatively warm air to the south and SW in this LOW.

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For the South of England the LOW will initially push warmer tropical air ahead with rain arriving for us in the SE on a warm front sometime Friday pm (top diag above Sat 00hrs).  The warm sector is likely to be windy with gusty SW winds and a considerable accumulation of rain, 10-20mm overnight into Saturday.  The warm sector tropical air mass (upper air +5C) could have temperatures near double figures whilst the polar air bearing down from the north is a much more frigid airmass (upper air -6C).  The contrast between these two airmasses could make the frontal rain particularly heavy while the cold front contrast could even have an odd rumble of thunder as cold air undercuts the warm and forces it aloft.  The skew-t diagrams below show the contrast in these two airmasses.

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The LOW centre crosses the North of England and into the North Sea overnight into Saturday when, due to it’s location under the left exit of the jetstream, it is forecast to deepen to possibly around 980mb. quite low especially for a depression located so near the shore.  Deepening occurs as the jetstream aloft encourages air to rise off the surface because air is diverging aloft.  So air is rising off the surface quicker than it can be replaced by air arriving: hence falling surface pressure. This commonly occurs when lows interact with jetstreams on their left hand side, near the exit of a jetstreak.

The classic frontal depression with cold and warm fronts separated by a warm sector only lasts for a matter of hours before the cold front, pushing forward more dynamically than the warm, catches up the warm front and pushes the remaining warm air into the upper atmosphere.  This is an occlusion and signals the end of the development stage of a depression.  The central pressure usually starts to rise after occlusion has occurred.

Whilst the situation is still uncertain, it is likely that Friday afternoon and Saturday will be windy and increasingly cold as the winds veer clockwise from the SW through to North and finally NE and E.  It is the latter NE and E winds that will bring the colder air to the UK and the SE especially.  Continental Europe is currently very cold so any air flowing from this direction will be chilly.  Cold crisp continental air will stay with us for a while as high pressure builds to the west and pushes north over Scotland while the LOW moves over Europe.  This setup allows easterly winds to flow over the UK.  Dry cold is expected as the pressure is likely to rise and stay high.  Expect some frosty nights. The duration of the HIGH varies between models but certainly should keep things cold and crisp through to the New Year.

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cold new year

Further ahead a split in the polar vortex and stratospheric warming are dominating weather chat and these are set to possibly bring colder conditions through January.  On the other hand, Phase 3-4 of the MJO (Madden Julian Oscillation) is usually associated with a positive North Atlantic Oscillation which brings milder westerlies to the UK.  So, it’s interesting times ahead, stay tuned and Happy Christmas!

So far December weather for Reigate and across much of S England has been much the same for a while: breezy westerly winds and exceptionally mild on occasions with December temperatures breaking records in Reigate: the highest December temperature of 12.7C was recorded on Dec 18, the highest average and highest minimum were also records broken this month in the town. The December CFS chart for Bournemouth temps show how much time they have been above average this month so far.  Whilst it has been mostly relatively mild this month so far in the UK, large parts of the rest of the N Hemisphere has been even warmer with much of N America and parts of Russia being anomalously warm too.  On the other hand E Siberia has been very cold with Verkhoyansk falling to -50C at times.

Whilst a colder spell is expected to arrive soon after Christmas this will not be sufficiently extreme or long enough to move 2014 away from a record breaking warm year.  The Central England Temperature records go back before 1780 and 2014 looks almost certain to be the warmest ever recorded CET with an anomaly of +1.49C above the long term average.  This matches 2014 as a warm year globally, if not quite the very warmest.

So, apart from the rather underwhelming “bomb” depression earlier in the month, why has the weather been so mild, uneventful and unchanging for much of December, so far?  An immediate cause of our quieter weather this December is the jetstream being less active than last year.  On the charts below spot how much more active the 2013 jet was at the same time last year across the Atlantic.  A succession of Atlantic storms were driven headlong at the UK by a powerful jetstream which sat further south.  This year the jetstream has mostly been further north than the south of the UK and has been more meandering (meridional) and less powerful: hence fewer and less powerful storms for us in the south, most of the storms have tracked to the north of Scotland which has had an “ordinary” December of high winds and heavy rain!

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The reason for our milder than usual December is that much of the time our winds have arrived from a warm SW direction round a persistent HIGH over Europe.  We have had few incursions of Arctic northerlies, as yet.  Nevertheless, for parts of the month especially for the NW of the UK, there has been a sustained NW wind associated with high pressure over the Mid -Atlantic and LOW pressure over Iceland and this has pegged down our overall temperature anomaly to 1C above long term average.  This pattern of broadly westerly winds is called zonal and is indicated by a positive North Atlantic Oscillation (pressure low over Iceland and high over the Azores).

While the jetstream controls our synoptic scale pressure patterns, a more remote driver of our overall weather in the Atlantic mid-latitudes is the rather more geographically far-flung “Madden-Julian Oscillation”.  The MJO is a cycle or wave of weather disturbances (clusters of convective storms) that start in the Indian Ocean and move east through the tropical oceans into the Pacific and beyond.  It usually peters out across the Atlantic but can be observed to continue as an unbroken oscillation into the Indian Ocean where it starts another Phase 1 again. The MJO connects up with observed known weather patterns in the Atlantic and has therefore got an impact on UK weather, especially apparently, in years of weak or neutral ENSO (el-nino southern oscillation).  This year is currently a weak El Nino.  With the MJO in Phase 3-4 then a positive NAO is usually favoured but is not fixed of course, yet more drivers are likely to influence proceedings in the new year, not least “sudden stratospheric warming”.
MJO Phase 3-4 = +NAO

MJO Phase 3-4 = +NAO

DIY forecast for the possible storm 27-28 December

When upper winds (including the jetstream at 300-250hPa) match the direction of those at the surface, the weather tends not to change very much over quite long periods, like recently.

winds the same at height: no change

winds the same at height: no change

Wind direction and air masses can tell us a lot about how the weather will change and sometimes this is helpful when forecast changes are uncertain or simply fail to arrive when expected.  To an observer on the ground clouds at different heights can sometimes appear to be moving in different directions.  If on such occasions, the observer sees the clouds moving perpendicular to each other then a rapid change in weather is likely to be on the way, either good or bad!  The so-called “crossed-winds rule” is handy if you want to know how quickly expected weather events will arrive, especially if you are out and about on a day when expected changes are afoot but the timing is uncertain from forecasts.  This could prove handy later this week when a large storm might upset our run of benign conditions but the exact timing of fronts and events is uncertain, especially at this range!

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The storm, expected to intensify rapidly in the Mid-Atlantic during Boxing Day (yes, a possible rapid cyclogenesis bomb depression) could take a track modelled by the GFS that runs from the N of Scotland down through the N Sea. This SE track could pull in strong Arctic winds and, combined with high spring tides and high waves, this could cause a storm surge event for E coasts of the UK.  Note this is too far off to be certain at this stage.

Other models, such as the ECM and UKMO have different tracks that take the LOW on a less potentially damaging course.  Nevertheless, the models are worth watching because on some tracks the synoptic situation is similar to the 1953 storm which caused a lot of coastal flooding.  Of course, sea defences are much improved since 1953 so, even if the track was similar, it would be unlikely to cause anything like the same impacts.

compare 1953 storm surge with models 2014

compare 1953 storm surge with models 2014

It is also noticeable how similar the zonal pattern preceding the 1953 storm is to the current synoptic pattern: a strong positive NAO was present with both (see below).

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Back to the present… a weak cold front moving south during Christmas Eve will introduce a cool N/NW polar air flow across the country by Christmas Day. No snow is forecast for the SE with this cold front and it will be noticeably colder but brighter on Christmas Day.  A high pressure ridge on Boxing Day could start the day bright and frosty but, depending on the final track of the RaCy depression, things could go downhill rather quickly thereafter.  If you are out for a walk on Boxing Day then this is where the Crossed-Winds rule will come in handy to do some of your own forecasting!  Here’s how:

Bozing Day crossed-winds rule

Bozing Day crossed-winds rule

It will be necessary to see clouds at different heights – especially those wispy cirrus ones to check high altitude jetstream winds.  If it is completely overcast then forget this unless you happen to see breaks in the low cloud.

Find the surface wind direction: look at lower cumulus clouds or just local wind vanes or weather stations. It’s important to get the correct surface wind direction though so don’t rush this bit.

Stand with your back to the surface wind : the simple rule means that any low pressure will be on your left.  You can also tell how quickly weather will change for you locality thus…

Watch the direction of any cirrus clouds: check this with an aerial or static object.  If they can be seen to move at all then they will be shifting fast, because cirrus can be 10km up! The best cirrus for this is hooked mares tales or jetstream cirrus which appears in long impressive streaks along the core of the jetstream or similar upper winds. The more fuzzy edge is on the tropical warm side and the firm sharp edge to cirrus, if this can be spotted, is on the polar air side.

 

Now, the rule: stand with your back to the surface wind and if the cirrus (upper winds) come from the left then the weather will get worse.  The more perpendicular the winds (right angles) the more rapidly the weather will deteriorate.

If the surface and upper winds are going the same way, then there will be be no immediate change, or just very slow change.

If the upper winds come from the right then the weather will start to improve.

On the back edge of the storm, chilly Arctic air could bring down an active cold front with snow showers on the back edge into the SE, but more likely these will be restricted to NE/East coast.  It’s ages away so no details are possible but this storm looks one to watch.

Finally, the longer range outlook is rather uncertain!  Signals such as stratospheric warming, forecast to take place into early January, favour a cool January with the break-down of westerly flows into occasional cold Northerlies / easterlies.  In contrast, the MJO seems to favour more of the same unsettled westerlies for a while at least.

Quite possibly it will probably be a mix of the two!  This is suggested by lastest output by the CFS showing some zonal westerly weeks and some potential cold northerlies with the subtle position of HIGH and LOW pressure being critical to the outcome.  Lots of interest over the Christmas period and beyond, keep watching the weather!

 

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The MetOffice charts above show the formation and life-cycle of a December 2014 “weather bomb”, involving the process more properly called rapid cyclogenesis. There are reasons why meteorologists dislike the term “weather bomb” but perhaps the most obvious is that the sensationalist short-hand use of the term “bomb” detracts from the complex processes and variable scale and location of impacts.  The term “bomb” tends to hype stories in the press that can cause over-reaction and unnecessary concern. On the other hand it gets people reading about the weather, which is a good thing (like this post, ahem!).

Nevertheless, a “weather bomb”, a term borrowed from the US and New Zealand, is short-hand for a potentially extreme event.  Bomb depressions are deep low pressure systems that form by the process of Rapid Cyclogenesis (RaCy for short).  RaCy is the rapid formation of a deep depression when the central pressure falls more than 24mb in 24 hours.  Such RaCy depressions are usually of marine origin. About 12 such RaCy bomb depressions hit the UK in the exceptionally stormy winter last year 2013.  Although by no means the most powerful, the first and most famous RaCy depression of last winter was the St Jude storm that hit Southern England with moderate force in October 2013.  Pictures below are from that event and can be compared to the enormous scale of the more recent Atlantic bomb depression of December 2014.

The “bomb” depression that struck this December 2014 seemed to catch media attention, despite the impressive weather impacts being almost wholly restricted to the less populated NW, especially Scotland, where people are entirely used to coping with such lively weather.

http://www.stornowaygazette.co.uk/news/local-headlines/weather-bomb-cuts-off-power-to-18k-homes-1-3630321

December 2014 rapid cyclogenesis: the weather story

The December 2014 “weather bomb” was a depression (low pressure system) which formed rapidly far out west in the Atlantic between SE Greenland and Iceland.  The formation was associated with a fast moving jetstream and the surface convergence of sub-tropical air from the south west meeting a frigid NW polar airstream from Canada and more local air direct from the Greenland ice cap.  The big temperature differences between these air masses accelerated uplift and the lowering of central pressure.

impressive but not the day after tomorrow

impressive but not the day after tomorrow

Descending dry stratospheric air is another defining feature of RaCy systems.  Cold dry air from aloft turbo-charges the depression as it is injected into the depression.  The cold air aloft increases lapse rates in the surface airmass and causes air to rise more purposefully creating a dramatic fall in central pressure.  Descending cold dry stratospheric air can be spotted on the water vapour satellite images as a dark dry slot ingressing into the depression circulation over time and following hard on the heels of the cold front as it is blasted across the Atlantic.  The water vapour images below show the rapid development of the system during Tuesday 8 December.  In later images it is possible to see the speckly cumulonimbus clouds emerging in the unstable cold sector following the cold front. Such instability was caused by the descending dry air.

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Rather than going through the rather measured development stages of a Norwegian Model cyclone, a RaCy depression usually follows a life cycle more like the Shapiro-Keyser model below (though at the time of writing I am not certain as to whether the December 2014 RaCy depression formally fitted all aspects of this model).  Several key characteristics of the December 8 cyclone fit the S-K model fit and this is the usual model associated with RaCy depressions.

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The Shapiro-Keyser depression life-cycle model often features a cold front that is blasted rapidly ahead.   so rapidly that it “fractures” from the wrapping warm front further north. This is known as a T-bone fracture and experts can identify the moment of fracture using satellite photos. Additionally, cf course, upper air moves faster than the surface wind that suffers frictional drag even across relatively smooth ocean.

satellite features of emerging RaCY depression

satellite features of emerging RaCY depression

This meant that the cold front moved so rapidly that it split vertically into a fast moving upper front and a slower moving surface cold front. The cold front literally had its head ripped off!  The frigid upper cold air travelled over a shallow moist zone of warmer sub-tropical air and it is this that increased lapse rates and caused immense instability in the polar air stream that eventually arrived in Scotland.  Instability can be seen on the visible satellite pics as speckly masses of cumulonimbus clouds shown best in the satpic above.  In the charts and sat pics below note the wind speed associated with this polar air and the tropical air preceding it in the warm sector.

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In the S-K model the cold front is sometimes weakened during the formation process while the warm front remains active, wrapping itself in knots around the central “eye” of the storm.  The 850mb chart below shows temperatures of this cold upper air at 1500m above Scotland. The bomb depression this December seems to have matched this because, while the cold front was relatively weak (narrow squall line) the exceptionally unstable polar air behind it was arguably the defining characteristic of this system, bringing persistent convective storms and an outstanding 5000 lightning strikes and thunder-snow blizzards across higher ground in Scotland during the advection of this exceptionally cold and unstable air for an Atlantic NW airstream.

In the S-K model depression life-cycle the warm sub-tropical air is eventually left “sequestered” as a warm pool trapped in the middle of the mature depression which is called a “warm seclusion”.  The usual process of occlusion is bypassed as the centre of the low fills with warm air.  Meanwhile, the rapidly overshooting upper cold front causes S-K cyclones to often elongate in appearance on surface pressure charts, a feature associated with the rapid forward acceleration of the cold front in relation to the tightly wrapped, almost stationary, wrapped warm front. It is this tightly wrapped warm front (sometimes shown as occluded on weather charts) that shows another defining feature of S-K depressions.

As our initial bomb LOW pressure moved due east and filled and decayed offshore near Norway, a wave depression further south on the Polar Front also “bombed-out” to the SW of the UK and swept across Southern England on Thursday-Friday 11-12 Dec.

This was a separate small scale system but technically another rapid cyclogenesis as central pressure fell more than 24mb in 24 hours, but only just.  This illustrates the varying scale of bomb cyclones: some cover vast areas, some a small.  The 11-12 Dec RaCy depression was much smaller in size and intensity, max wind speeds were much more restricted and the whole system several magnitudes smaller in scale than the “mother” cyclone further north. Charts below show the evolution of this storm.

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Finally, the North Atlantic Oscialltion is a measure used to describe and forecast the mean pressure pattern over the Atlantic. A positive NAO indicates “normal” conditions with low pressure over iceland and high over the Azores. This is associated with a zonal west to east flowing jetstream and fast moving cyclones moving rapidly west to east bringing generally mild conditions to the UK in winter. Note the recent positive pattern matching the westerly flow and active zonal jetstream causing the RaCy depressions.  When the NAO turns negative the jetstream is often more wiggly and flows between latitudes in a more meridional flow potentially bringing cold air from the north when pressure patterns are more slow moving and even “blocked”.  A negative pattern is often associated with cold winter weather for the UK. The NAO is not a driver of weather, merely an indicator of pressure patterns.

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For a bit of fun we invented our own local Wight-Wash Oscillation (WWO) which is a measure of pressure across the south of England between The Wash and the Isle of Wight.  This would give an approximately similar local version of the NAO but just for fun!  We noted a WWO difference in pressure of 10mb during St Jude and only 9mb during the recent bomb wave depression.  The WWO particularly suits the passage of wave depressions across the Midlands which tend to yield the highest wind speeds for the SE.  It would also work in negative conditions which would give cold easterly winds in winter. Note this measure is just for fun!

Positive NAO remains likely on the run-up to Christmas 2014 so chances of a White Christmas is much reduced. Remember that a White Christmas for us in SE England is the rare exception to the rule.  On a brighter note, the earliest sunset has just passed and we can at least look forward to later sunsets from now on!

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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.