Dr. Eddy Graham's Hebridean Weather Blog

by Dr. Eddy Graham

Edward Graham's Journal (Details)

Heatwave? Well, certainly A LOT warmer

Posted by Dr. Eddy Graham on 04 May 2016, 10:37 PM


Due to persistent lower-than-average sea surface temperatures in the North Atlantic Ocean, the highest temperature during the whole of April in Stornoway was a mere 11.4degC, colder than the highest in either January or March of this year!

Yet all of this is to change from this Sunday (8th May) onwards as winds switch from the prevailing cool northerlies and westerlies of recent, to a much, much warmer easterly, coming straight off a rapidly warming continent.

To watch out for? Pressure will decrease quickly over the mainland from Tuesday onwards, so widespread thunderstorms are likely inland by mid-week. Haar is often a problem too on onshore coasts during early heatwaves.


Attached files Attachments 1

Heatwave.jpg (73.4KB) - Download

Coldest night of winter in Stornoway - on April 28th!

Posted by Dr. Eddy Graham on 29 April 2016, 10:18 PM

Severe spring frost

In a past 12-month period that has seen the meteorological seasons practically reversed, the recent abnormally cold late April weather has brought heavy snow, large hail, severe frost and bitter winds across Scotland.

Amazingly, Stornoway town actually reported its coldest night of the 'winter' on 28 April 2016, with -2.9degC (grass min of -5.4degC) recorded at the Met-Office spec station in the town centre. The -2.9degC value is lower than any recorded during the normal winter period of December, January and February (or indeed March) - the next coldest night was 27 Feb with -2.3degC.

Drier soils, lighter winds, cooler sea temperatures and more frequent northerly airflows in late winter usually mean the lowest night-time air temperatures are often reserved for late January or February in the Hebrides - but it is highly unusual to have the absolute lowest so late in the season on 28 April, a mere 8 weeks from midsummer.

It is noted with interest that 2015 also saw very low air temperatures as late as 1st May (-4.5C at Lews Castle meadows, the 2nd lowest value of that year). 

All this follows on from some remarkably topsy-turvy variation in seasonal weather over the past 12 months (2015 was the worst summer in least a century in western and northern Scotland; Scotland also experienced the astonishingly record wet December 2015).



Attached files Attachments 1

frost-1149002_1920.jpg (540.3KB) - Download

Celestial Landscapes: Art, clouds and science

Posted by Dr. Eddy Graham on 14 April 2016, 11:02 AM

Come and see @eddy_weather in action at the Inverness Science Festival on 29 April next!


WHEN? Friday, 29 April 2016 from 17:30 to 19:00

WHERE? University of the Highlands and Islands STEM hub - 1 Inverness Campus Beechwood Campus, Inverness IV2 5NA, United Kingdom - View Map


Clouds cover 40-50% of the earth’s surface at any one time – yet, how often do we get the chance to pause from our busy schedules and look-up to fully appreciate the beauty and spectacle of our ever-changing celestial landscape? In this lecture, Dr. Eddie Graham (FRMetS), will show, with the aid of photographs and time-lapse animations, how an initial aesthetic appreciation of clouds can quickly translate into a enhanced understanding of the meteorology and science behind clouds, by simply ‘looking at them from both sides’.

This event is part of the Inverrness Science Festival and will take place at the University of the Highlands and Islands STEM hub, Room 51 in the building behind Inverness Campus.


Attached files Attachments 1

proxy.jpg (39.9KB) - Download

Glorious summer ahead as scientists find way "to stop rain"

Posted by Dr. Eddy Graham on 01 April 2016, 6:56 AM

A new scientific breakthrough in cloud physics means this summer "could be the best yet" over the UK, reports @eddy_weather.

Line convection over Lewis and Harris

Project FAIR-LOOP-l, a consortium which has revolutionised a new cloud-seeding technology, announced this morning that they will be using their fleet of new airplanes, currently based in western Scotland and Ireland, to seed the clouds from above on a daily basis during the coming summer. Their operation will make the clouds "rain-out" all their precipitation before reaching the UK, thus ensuring sunny skies and a "barbeque summer" for all.

The expected change in weather will be especially welcome in the Scottish Highlands says FAIR-LOOP project manager Dare H. Tweedy, as last summer (2015) was a washout - "the worst in nearly 200 years".

It's a "win-win" situation adds Tweedy because "since the weather will be drier there'll be far fewer midgies too, so that's an added bonus". A severe drought for the whole of the UK is unlikely however, as the cloud-seeding planes will only be in operation during the daytime (due to current EU working-time and health-and-safety legislation) and so "some rain is still likely at night-time" according to Tweedy.

FAIR-POOL says it has funding for exactly one year only due to UK government austerity measures and spending cutbacks on research. Pending success, interested parties with a view to expanding the project for perennial summer weather are asked to DM @eddy_weather on Twitter for further information.


1 April 2016

Attached files Attachments 1

clouds-429228_960_720.jpg (72.6KB) - Download

Excellent examples of line convection

Posted by Dr. Eddy Graham on 31 March 2016, 5:37 PM

Line convection is a bit like 'strip-the-willow line dancing' - it's a narrow line, but it's very exciting, energetic and goes on forever!

Yesterday and today (31 March 2016), due to the slack cyclonic synoptic airflow upon us, and together with the strong post-Equinoctial sunshine, meso-scale conditions were ideal for the formation of morning sea-breezes followed by powerful inland convection.

Yesterday saw a narrow convection band lined North-South over the Uists (see image). Today, it was the same thing over Lewis and Harris (see 2nd and 3rd images), although there was enough upper streamflow to force the latter line east into the Minch by 5pm. Glorious sunshine, followed by heavy showers occurred in both cases.

Uists white cloud line convection

Line convection over Lewis and Harris

Line convection over Lewis and Harris


Attached files Attachments 3

Capture.PNG.12 (45.9KB) - Download

29Mar2016-Uist-Line-Convection.PNG (25.4KB) - Download

Capture2.PNG.3 (698.9KB) - Download

Happy St. Patrick's Day

Posted by Dr. Eddy Graham on 17 March 2016, 5:51 PM

What stunning St. Patrick's Day weather for Stornoway!

Green island

Apparently the island has turned green too! (NASA MODIS Terra satellite image), as it emerged today from the haar surrounding most Scottish coasts today.

Altogether over past four consecutive days, we've had nearly 35 hours of sunshine (about 80% of the maximum possible), with air temperatures rising up into the teens (High of +13.5C in Stornoway town on St. Patrick's Day, low of +0.7C on the crisp frosty mornings, -3.1C on the grass).

Alas, the glorious weather ain't to last, as the breeze has now turned onshore and the haar and low cloud will likely be dominant over coming days, though some breaks are possible.


Attached files Attachments 1

Capture.PNG.11 (629.5KB) - Download

There's 7% extra weight on your heid today!

Posted by Dr. Eddy Graham on 15 March 2016, 3:31 PM

We live at the bottom of an ocean of air, known as the 'atmosphere'. So, in much the same way as if we dived to the bottom of the sea, the total weight of air above our heads causes a compressive force on our bodies at sea-level -> this force is air pressure. In physical terms, this is simply measured as the mass of air over every metre, per second every second (or even more simply, newtons per square metre). 

Today, the Ides of March (15th), we have an enormous high pressure zone sitting over Scotland (see chart) with a super-tremendous central pressure of 1040hPa. In simpler terms, that's the same as 10,400 kg (over 10 tonnes) of air acting over each metre per second, every second.

Frosty grass Frosty grass

During the past winter, air pressure was often below 970hPa during the frequent storms that battered our coasts and country. When understood as kilograms per metre over time, this means that the force acting on our heads today (i.e. weight of air acting on our heads) is some 7% greater than during the past winter!

However, unless you are super-sensitive, I doubt that you can feel a tangible 7% more compressed today!

@eddy_weather, Stornoway, 15 March 2016

Attached files Attachments 2

Capture0.PNG (31.4KB) - Download

Capture-2.PNG (2.4MB) - Download

Hint of spring ahead next week...

Posted by Dr. Eddy Graham on 10 March 2016, 6:21 PM

The mornings may still be frosty, and the grass still yellow with few, if any, shoots of green... but there's a (slight) hint that Spring may be just around the corner...

Frosty grass

At the moment, the met models are indicating much milder weather for all of Scotland over this weekend, but with plenty of rain along the west coast and through the Highlands. However, from Tuesday onwards, pressure will rise again from the east - hopefully bringing glorious skies and warm air, with the air temperature reaching into the teens degC... let's wait and see!

N.B. Fine weather in spring always brings the risk of haar too, so don't get too excited yet!


Stornoway, 10 March 2016

Attached files Attachments 1

morning-frost-on-grass.jpg (108.4KB) - Download

Muirneag, Beinn Bharabhais with dustings of snow

Posted by Dr. Eddy Graham on 27 February 2016, 9:59 PM

Glorious clear skies today (27 Feb 2016) reveal dustings of snow still lying on Muirneag and Beinn Bharabhais (Isle of Lewis), as seen by the NASA Terra satellite sensor. Further south, the snow-capped hills of Harris and Uig stand out like icebergs against the faded winter landscape shades.

Stornoway snow

N.B. Last night was the coldest night of the winter in Stornoway town so far, with -2.3degC measured at 06 UTC. Possibly even colder tonight.


Attached files Attachments 1

Capture.PNG.10 (650.7KB) - Download

Sneachd 's Grian ann an Steornabhagh

Posted by Dr. Eddy Graham on 24 February 2016, 2:54 PM

Bha e uabhasach breagha ann an Steornabhagh an-diugh - Seall na dealbhan!

Stornoway snow

Stornoway snow

Stornoway snow

Stornoway snow

Thuit 2cm sneachd tron oidche 's tron an mhadainn. Bha an temperature as isle -1.1C, agus bha -4.9C air an talamh.


27 An Gearran 2016


Attached files Attachments 4

tn_P2240235.JPG (27.7KB) - Download

tn_P2240171.JPG (28.5KB) - Download

tn_P2240213.JPG (32.4KB) - Download

tn_P2240180.JPG (42.3KB) - Download

NASA Terra images snow extent

Posted by Dr. Eddy Graham on 18 February 2016, 2:54 PM

One of the most useful and versatile satellite sensors in operation today is surely NASA MODIS Terra. Using a combination of visible and infra-red radiometer detectors, the various channels can be combined in a way to identify and distinguish almost any type of surface from space - including snow.

In the images from today (Thursday 18 Feb 2016), thanks to clear skies over most of Eastern Scotland, we can see the snow extent as cyan (channels 7, 2 and 1) and mauve (channels 3, 6 and 7).

Black Frost Black Frost

Yesterday (17 Feb) we could also clearly distinguish the peaks of Toddun, Beinn Mhor na Hearadh and Beinn Mhor, Uibhist a' Dheas, on the 7-2-1 image for the Western Isles (see below)/

Black Frost


Attached files Attachments 3

Capture3.PNG.1 (582.7KB) - Download

Capture4.PNG (575KB) - Download

12744557_1561729767473708_3494341501687876581_n.png (314.1KB) - Download

Beware of the Black Frost!

Posted by Dr. Eddy Graham on 13 February 2016, 9:53 PM

There has been a very welcome switch to 'easterly' weather over the past few days across the Hebrides - with low relative humidities permitting an excellent clarity to the atmosphere.

However, one of the risks of such low humidity means the wet-bulb depression is enhanced (evaporation is enhanced), and in such conditions an ice-bulb effect can be observed (see chart).

Black Frost

The result is an invisible 'black' frost - this occurs when the ground and objects freeze, but there is no trace of a visible 'hoar' frost (normally caused by humidities reaching 100%, which isn't the case at present across the Isles). With low relative humidities, this can happen even with air temperatures well above freezing (e.g. +2, +3degC)!!

So you have be warned - beware of the black frost!

Postscript (14 Feb 2016): Today I realise that I may have confused some folk with the graph above. Here's a hopefully better pic i.e. If the air temperatures is +2.5C and relative humidity is 60%, and a wet surface (e.g. grass, ground) evaporates to the drier air above, it actually cools right down to -0.0C (and thus could freeze as a 'black' frost, with no visible 'hoar' frost). The drier the air, the greater the potential cooling! (just as we've had recently):

Black Frost


Attached files Attachments 2

BlackFrost.PNG.1 (16KB) - Download

Black-Frost1.png (18.9KB) - Download

Nacreous clouds: A beautiful spectacle or a terrible beauty?

Posted by Dr. Eddy Graham on 05 February 2016, 12:58 PM

One of the most widespread displays of nacreous clouds ever witnessed in the British Isles took place recently over 1-2 February 2016. In some places (such as Dublin, Ireland), there is no recorded evidence of any previous occurrence, right back to the 19th century, at least (Dixon 1953).

Most of central and southern Scotland, northern England (including Manchester and Leeds) and eastern Ireland witnessed the clouds over an unprecedented length of time. In Dublin, the clouds apparently remained in the sky for nearly 48hrs (again a very unusual duration). A few example photographs are shown below (courtesy Garry Quinn photography and Kieran Commins, Met Eireann).

nacreous clouds

By gquinnphotography.com

nacreous clouds

By gquinnphotography.com

The clouds were coincident with an moderately-intense ozone hole of 200-250 DU (Dobson Units) over north-west Europe (normal ozone is about ~360 DU) - lower values have been documented in the past, for example 165 DU in November 1999 (Graham 2002). This is to be expected in this case, for ozone is responsible for heating of the stratosphere - and so a lack of it usually means a colder stratospheric air temperature. If cold enough (below -80 to -85degC), nacreous clouds (also known as 'Mother-of-Pearl' or 'PSC: Polar Stratospheric Clouds') can form.

nacreous clouds

By Kieran Commins (Met Eireann)

The clouds involved in this display were generally considered to be Type 2 PSC, and so not directly involved in ozone depletion. However, it is possible that some Type 1 PSCs may have been present too (they deplete ozone at a rate of about 1% per day). Some photographs of suspect PSC Type 1 clouds were taken early on 3 February (please ask author if interested). 

The ozone layer is, of course, vital for life on Earth. Without it, we would suffer from harmful UV radiation, which causes skin cancer and damages crops. Northern Hemisphere ozone, although nowhere nearly as low as in the Antarctic, has shown some loss in recent decades.

Here's the Northern Hemisphere ozone distribution for 2 February, courtesy of NASA Ozone Arctic Watch (http://):

nacreous clouds

As stated by Hood and Manny (2002), such holes in the Northern Hemisphere are mostly caused by dynamics in the stratosphere, and the contribution from ozone depleting PSCs is minimal.

And here's the 30hPa air temperatures (about 24km, which was the height of the clouds during the November 1999 event, as shown by Graham [2002], courtesy of NOAA CPC (http://):

nacreous clouds

As you can see, there's a clear minimum of stratospheric air temperature below -80degC, located right over the UK/Ireland i.e. highly suitable conditions for PSC formation.

And finally, on Twitter on 2 Feb, I'd thought that I'd spotted the nacreous clouds themselves on NASA Terra Channels 7-2-1. It looks like there was a hydraulic jump generated by the very strong west wind (nearly 200kts at jetstream level) hitting the Wicklow mountain perpendicularly, side-on (see sat image below). Dörnbrack et al. (1999) state that the air temperature can drop significantly in stratospheric mountain wave crests (due to rapid uplift). In the case of 1-2 february, the air was likely cooled rapidly to saturation and a low-enough temperature for PSC formation (i.e. below -85degC).

However, closer analysis of MetOp imagery shows that this particular cloud had a cloud top temperature of only -30C to -40C. So alas, no PSC! (they are probably too thin optically to be seen on standard visible/infra-red satellite imagery, Graham 2002).

nacreous clouds nacreous clouds nacreous clouds 

(with thanks to Bernard Burton of http://www.woksat.info/ for this final image)

Conclusion: Whilst outstandingly beautiful, a more holistic view of these clouds could easily be 'Harbingers of Doom'. I think more research is needed on the exact causes of this outstanding display.

Appendix: Nacreous clouds (such as above) form in the lower stratosphere between 20-25km. Previous sightings near/around the British Isles include the following:

  • 16 Feb 1996: Northern England
  • 30 November 1999: Aberdeen and E Scotland
  • 19 January 2008: Belgium
  • 9 December 2012: Aberdeen and Isle of Harris
  • 1-2 February 2016: This event

i.e. Their incidence appears to be on the increase during recent decades, which is in line with global ozone depletion caused by human pollutants, but it may also be coincidence.

Websites on previous sightings:


Stornoway 5 February 2016


Dixon, F.E. (1953). Weather in old Dublin. Dublin Historical Record13(3/4), pp.94-107.

Dörnbrack, A., Leutbecher, M., Kivi, R. and Kyrö, E. (1999). Mountain‐wave‐induced record low stratospheric temperatures above northern Scandinavia.Tellus A51(5), pp.951-963.

Graham, Eddie. "Nacreous clouds in November 1999 and record low ozone."Weather 57, no. 3 (2002): 107-109.

Hood, L.L. and Manney, G.L. (2002). Nacreous clouds. Weather57(10), pp.393-394.


Attached files Attachments 8

12615710_502590516614963_8174532597296856421_o.jpg (102.3KB) - Download

11207340_502590513281630_9165838211728579739_n.jpg (99.3KB) - Download

12646989_10208347186100265_7470811864870814513_n.jpg (24.3KB) - Download

CaPTJL7WAAIO5pq.png (390.2KB) - Download

CaPLU5sWYAAemZP.png (89.6KB) - Download

CaSwCDAXEAE3mTK.png (781.5KB) - Download

02Feb2016-IR.PNG (682.1KB) - Download

Legend.PNG (15.7KB) - Download

No @eddy_weather!

Posted by Dr. Eddy Graham on 31 January 2016, 3:54 PM

Alas, Eddie has come down the the lurgy recently, so I'm not issuing any weather news or updates at the mo, thank you @eddy_weather

Wild weather for Burns' week

Posted by Dr. Eddy Graham on 24 January 2016, 9:10 PM

It's Burns' Day tomorrow (Mon 25 Jan), and after some very pleasant but cold winter weather over the past two weeks, it's looking likely that we'll see a return to more seasonal winds, heavy rain and gales over the coming week - much as happened in the year of Burns' birth.

Scotland's Greatest Bard - Robbie Burns

A severe gale is possible on Tuesday accompanied by heavy rain. More heavy rain and further gales will follow during the week, and it may turn much colder (with brief snow) at times later in the week.

Keep posted with me on Twitter at: @eddy_weather

Attached files Attachments 1

robbie-burns.jpg (8.3KB) - Download

Snow extent across Scotland

Posted by Dr. Eddy Graham on 15 January 2016, 11:12 AM

Sneachd (gorm) tro na Crìochan na h-Alba 's an Gàidhealtachd an-de (as seen by the NASA Terra satellite) @eddy_weather

Scotland snow extent

Attached files Attachments 1

Capture.PNG.9 (1.3MB) - Download

Never promise snow to children unless you are certain!

Posted by Dr. Eddy Graham on 10 January 2016, 11:07 PM

Recent weather updates on @eddy_weather

Lesson #1 in Forecast Meteorology:

Snow by Henryk Żychowski

Every year, in every country which has a winter, the forecasting pros (and not-so-pro) almost always stumble up at least once with one of the following errors:

Type 1:  You fail to forecast snow and it snows -> bad for you as your local council will be mad, but who cares, as the kids are delighted and it's a surprise snowfall, yippee!

Type 2: You forecast snow and it doesn't come -> worst case scenario as the council is still mad and your kids hate you too for months!

So what's it to be? Snow or no snow this week?

Update Tue 12/1/16: Probability of significant lying snow this week is reducing now; Wed pm is colder, but maybe Thurs milder. Then colder again Fri, let's see!

Original Post Sun 10/1/16: Currently, for Stornoway and the Hebrides, it's looking slightly possible that we may get some lying snow for a day or two between Wednesday and Friday of the coming week - but it won't last, it'll probably be gone by the weekend as mild southwesterlies will soon return. Of course the snow will come earlier on the Clisham - watch out for ice too!

P.S.. I note the astronomical tides are very high tonight and tomorrow. With a low air pressure of 970hPa tonight, the combined tide and surge could be +5.5m, so please watch out if you're near the coast at high tide.



Attached files Attachments 1

snow.jpg (65.6KB) - Download

1st Anniversary of the Stornoway 'Hurricane''

Posted by Dr. Eddy Graham on 08 January 2016, 5:02 PM

Tonight, 8/9 January 2016 is the first anniversary of the Stornoway 'Hurricane', the most powerful storm to affect the British Isles for over 20 years. At its peak, winds reached hurricane force 12 during the night at Stornoway Airport, with a peak gust of 113mph - the strongest in the UK since the 1990s. It was about as severe as Hurricane Debbie of 16 September 1961.

Here's a remainder of some of the damage / synoptic chart that night:

Tonight is also the 176th anniversary of Ireland's greatest natural disaster, Oíche na Gaoithe Móire ('Night of the Big Wind') when hundreds died in a ferocious hurricane, the severity of which has hardly been equalled over the past 300-400 years. It strongly impacted Scotland too, with air pressure dropping to 931hPa in Shetland.


Attached files Attachments 3

1939673_824717037576318_4270623644161307860_n.jpg (9.5KB) - Download

2015-04-03 18.44.43-B.jpg.1 (101.9KB) - Download

2015-03-16 13.41.33.jpg (219.6KB) - Download

Strong easterly winds promote good drying

Posted by Dr. Eddy Graham on 06 January 2016, 9:27 PM

The tale is told in the weather statistics:

  • The first six days of January 2016 have yielded a tiny total of 0.9mm (0.03in) of precipitation (rain) in Stornoway town
  • The final six days of December had... wait for it... 67.3mm (2.65in) of rain! (75 times more)

All because of a change in wind direction i.e. an offshore, easterly!

And although chilly, the lovely dry wind has meant some excellent drying conditions following seeming endless weeks of rain.

@eddy_weather, Stornoway, 6/1/2016

Attached files Attachments 1

washing.png (179KB) - Download

Stornoway 2015: Third Wettest Year at Airport Since 1930

Posted by Dr. Eddy Graham on 02 January 2016, 1:12 PM

Based on official Met Office data, the year of 2015 was the third wettest year on record in the vicinity of Stornoway Airport since 1930, with a total of 1494mm of rain falling. It ranks behind the two wettest years 1990 and 1999 which had totals of 1543 and 1547mm, respectively.

Incidentally, Stornoway town (a generally wetter location than the Airport) recorded 1680mm (66 inches) of rain during 2015.

The long-term trend in rainfall at Stornoway Airport (shown below) indicates an increase in variability and extreme high annual totals over the past 30-40 years.

Attached files Attachments 1

SYY-03026-Annual-Precip-1930-2015.png (26.2KB) - Download

Stornoway December 2015 Weather Statistics

Posted by Dr. Eddy Graham on 31 December 2015, 11:51 PM

It was an exceptional month by any measure, climatological or otherwise, although not quite as extremely wet (in terms of anomalous deviation) as parts of southern Scotland, Ireland and northern England (where there has been unprecedented flooding).

It was also an astonishingly warm month in southern England, where the average temperature was more equivalent to late April/May, and flowers therefore came out in bloom (though it was somewhat less mild in Stornoway). These extreme events appear to have occurred in concertina with other worldwide phenomena, such as El Niño and climate change.

Overall it was the 2nd wettest December on record in Stornoway - but the record was only set two years ago in 2013!  And so it ranks alongside 2013 as one of the most extraordinary months of recent times (although what defines 'extraordinary' now in a new climate world is open to question!).

Provisional Stornoway town December 2015 Stats:

Average daily high: 8.8degC (+1.2 above normal)

Average daily low: 3.6degC (+0.9C above normal)

There were an unusually high number of nights during the 2nd half of the month with near-record air temperature in excess of 12 to 13degC.

Precipitation: 280.7mm (11 inches - some 215% of normal i.e. more than double)

Thunder days: 1

Days with hail: 6

Snow falling: 4

Grass Frosts: 14


Attached files Attachments 1

1909859_1541138319532853_4621441901860555513_n.jpg (147.5KB) - Download

YES there's a 'Hurricane' (Force 12) offshore - but NO it's not (all) coming our way!

Posted by Dr. Eddy Graham on 28 December 2015, 5:35 PM

An extraordinarily deep and explosive depression (name 'Frank') will shoot up the Rockall Trough towards Iceland during the afternoon and evening of Tuesday 29 December. On its southern flank, winds are expected to reach Hurricane Force 12 (Cat 1 Saffir Simpson Hurricane), or astonishingly, perhaps even a Category 2 force on the hurricane scale. A storm of this severity is extremely rare, even in winter in the North Atlantic.

However, the centre of the 'Hurricane' Frank will stay offshore, meaning we will be troubled only by its 'tail-end' (frontal system) during the late afternoon and evening. Even so, winds are still expected to reach storm force 10 around the Hebrides, possibly violent storm 11 off the southwest of Uist and Barra. This means gusts of 75-90mph, so it's still dangerous.

The intensity of the winds (sting jet, cold conveyor belt) over Rockall can be seen on the NAVGEM model output for 18h Tues - a jet core of 85mph MEAN SPEED is predicted - this is most rare (gusts possibly in excess of 120mph)! 

We need be very thankful that the storm centre won't make landfall on Ireland or in Scotland. I'll be posting updates on Twitter @eddy_weather



Attached files Attachments 1

NAVGEM.PNG (34.8KB) - Download

Severe Gale /Storm Wed 23 night into Christmas Eve - Then colder

Posted by Dr. Eddy Graham on 22 December 2015, 9:38 AM

Just a quick update - it's still looking like being very windy overnight Wed 23 / Thurs 24 Dec (Christmas Eve), with severe gale to storm force southerly winds, veering south-westerly (perhaps westerly) later.

At present, it looks like the region of strongest winds (sting jet, cold conveyor belt) will stay (just) offshore to north-west of the Butt of Lewis, but model agreement has not been good recently, neither on the path nor the intensity of this low. So there's still a chance of more extreme winds than forecast (i.e. 80-90mph) - so watch out and take care if you are out and about doing training for Santa deliveries.

The storm will sporadically usher in much colder air for a while -> so the risk of a few snowflakes (and icy frosts) in the days after Christmas should not be ruled out!




Relentless Rain and Wind to Continue for Christmas Week: Risk Storms too

Posted by Dr. Eddy Graham on 20 December 2015, 5:39 PM

The seemingly relentless wind and rain of 2015 look like continuing for the foreseeable future... and it's worth keeping an eye on the weather forecast (from reliable sources such as the Met Office or Met Eireann) as one or two major storms could spring up with short notice.

Current focus is on a violent low forming west of Ireland early on Christmas Eve (with possible hurricane force winds near its eye; may be named #Eva), but most model predictions have kept the worst offshore yet. Keep posted on Twitter for any updates: @eddy_weather

PV anomaly and 500hPa geopotential of Christmas Eve '#Eva' low (FNMOC NOGAPS):

Attached files Attachments 1

Capture.PNG.8 (22.8KB) - Download

I'm dreaming of a Black Christmas....

Posted by Dr. Eddy Graham on 17 December 2015, 10:50 AM

With a combination of extremely mild tropical southerly winds, a globally-warmed world enhanced by an extreme El Niño, this December and Yuletide is shaping up to be anything but white!

So here's @eddy_weather's Black Christmas 2015 forecast for you!

I’m afraid it's going to be anything but a white Christmas this year – instead, it’s much more likely to be dark, windy and grey with frequent heavy rain and gales in the days leading up to, and probably beyond, Christmas Day. There’s also the possibility of a major storm or two next week, though we’ll have to wait closer to the time for any warnings to be issued (take note that 'Eva' and ‘Frank’ are awaiting on the list of coming named storms!). So I expect Santa will need to plan his journey carefully, taking advance note of ferry cancellations, and I would certainly hope that he doesn’t leave his last minute shopping until late on Christmas Eve!

(NASA MODIS inverted snow image) @eddy_weather
Attached files Attachments 1

Snowy-Scotland-21dec2010-Black.jpg (158.3KB) - Download



anonymous profile picture
Comment removed by the owner
anonymous profile picture
Comment removed by the owner
anonymous profile picture
Comment removed by the owner
anonymous profile picture
Comment removed by the owner
58849 page visits from 1 March 2013 to 5 May 2016