Severe Storm System & Arctic Blast Thursday 5th Onwards

[Liam J]

The center of the LP just NW of Iceland a short while ago.

 

download.jpg

 

The centre is to the south of Iceland under the developing hammer head of cloud, perfect image there of rapid cyclogenesis under way! 

 

Roughly where the NAE has the depression around 9pm. 

 

Look at the wind field! 

Edited December 4, 2013 by Liam J

[Richie V]

Hey pit, does the sheffield storm shield deflect wind round you too?

I like watching your live station in situations lije this

[WillinGlossop]

Gusts around 40-50mph over NW scotland/Islands now, steady increase in wind speeds. http://www.xcweather.co.uk/GB/observations

Check pressure......that gradient coming into western scotland..... Ouch.....

[The PIT]

Up to 55 mph new high. Perhaps ahead of schedule then?

[WillinGlossop]

Xc weather great site but updates every half hour even if half the sites only update every hour..... So can give some strange looking readings between locals sometimes...

[Matty M]

South Uist will receive a really bashing, but this would be to some extend expected in that location, would not surprise me to see it hit 100mph but you wouldn't see that inland.

Edited December 4, 2013 by Matty M

[Cloud 10]

The centre is to the south of Iceland under the developing hammer head of cloud, perfect image there of rapid cyclogenesis under way! 

 

Roughly where the NAE has the depression around 9pm. 

 

nae1.gif Look at the wind field! 

 

I thought it looked a bit off when comparing with the NAE,although there is a definite circulation

in the area i highlighted when the satellite animation is played.

 

Satellite: Europe – yr.no

[Liam J]

Western Isles will be the first to experience severe wind gusts shortly after midnight, so things getting pretty lively up there over the next couple of hours.

[Liam J]

I thought it looked a bit off when comparing with the NAE,although there is a definite circulation

in the area i highlighted when the satellite animation is played.

 

Satellite: Europe – yr.no

 

Yep you can see the circulation to the NW of the main low, and on the NAE chart.

[WillinGlossop]

100 kmph gusts in oslo already......

http://www.wetterzentrale.de/pics/Reurmetg.html

[radiohead]

997mb at 8pm, south of Iceland. Based on a blend of model estimates and observations. Will get a more accurate estimate later as the center moves closer to buoys etc :

 

http://meteocentre.com/analyses/map.php?map=NEurope&date=2013120420&size=standard〈=en&area=eur

 

This updates about 12 minutes past the hour with model data and then updates again closer to the top of the hour with observations integrated into the plot, thats the one to use.

[Mokidugway]

I wonder if it will produce a sting jet like in 2005, that storm caused quite a bit of damage around here !..

[Cloud 10]

997mb at 8pm, south of Iceland. Based on a blend of model estimates and observations. Will get a more accurate estimate later as the center moves closer to buoys etc :

 

http://meteocentre.com/analyses/map.php?map=NEurope&date=2013120420&size=standard〈=en&area=eur

 

This updates about 12 minutes past the hour with model data and then updates again closer to the top of the hour with observations integrated into the plot, thats the one to use.

 

Another great link there.

 

The 9pm update shows that small low that i was harping on about behind the "main man"

 

http://meteocentre.com/analyses/local/archive/2013120421_eur_full.gif?1386191359

[BurntFishTrousers]

Actually, the low itself has not (yet) deepened that rapidly. What is noticeable is the tight gradient from the high now interacting with the low and this will soon become clearer as the high gives way to a monster winter system incoming..

Edited December 4, 2013 by BurntFishTrousers

[BurntFishTrousers]

In fact, the high is being toppled now by the low. Here she comes..

[Liam J]

North Atlantic analysis chart, developing hurricane force.

 

 

 

[Paul]

Worst east coast tidal surge in 30 years may be on the way according to the Environment Agency:

 

http://www.netweather.tv/index.cgi?action=news;storyid=5553;sess=

[lorenzo]

Not long in from work and pretty damn cold and breezy out there already.

 

From the Eumetsat eport, this grab shows the RGB Airmass and Satellite.

 

The overlays in beige are for the 300hPa streamlines, and also the Isotachs which highlight the jet in yellow.

 

80 meters per second equates to a 178mph jet.  Classic European windstorm.

 

[BurntFishTrousers]

Worst east coast tidal surge in 30 years may be on the way according to the Environment Agency:

 

http://www.netweather.tv/index.cgi?action=news;storyid=5553;sess=

Does that mean we'll have Sky News cameras at the ready like previous times?! 

[Vorticity0123]

The precursor low of the storm has indeed formed to the southwest of Iceland. Currently, there is a comma-cloud formation present at that area. The surface analysis of the KNMI (HIRLAM) shows the development of the system:

The precursor storm is the 1005 mb low to the SW of Iceland
 

Six hours later, the system is deepening quite rapid (to 995 hPa in the picture) located to the northwest of Scotland.

 

However, at Thursday 6UTC (only six hours later), the low pressure area has attained a pressure of below 970 hPa

 

This would mean a pressure drop of on average 4 mb/hr! (on this six-hour interval)

 

The main reason for this event to occur is because the low pressure area is in the left exit of the jet stream¹

The low pressure area is in this image on the extreme southeastern tip of Norway.

 

For the wind analysis, the Hirlam wind output will be used:

This is the wind map for Thursday 07 GMT. It shows that a rather severe 11 Beaufort (No BFT this time  ) impacting the northwest of Schotland. This could result in quite heavy wind damage there.

 

The wind map for Thursday 13GMT shows that the wind field has moved southeastward along with the low pressure area. It shows a 10BFT impacting the northern tip of The Netherlands and western Denmark. Because the wind is also northwesterly, there is a chance of rather extreme high tide occuring in the countries adjacent to the North Sea.

 

One final thing i'd like to point out is that there is a storm warning of some sort (code yellow or code orange) for the northern part of Holland for 29(!) hours. The codes indicate a 3 hr span of wind gusts of up to 100 km/h, thereafter an 8 hr span of wind gusts up to 130 km/h, and finally another 19 hrs of wind gusts up to 100 km/h. The duration of the storm makes it even more dangerous.

 

Sources:

http://www.knmi.nl/

¹http://rammb.cira.colostate.edu/wmovl/vrl/tutorials/satmanu-eumetsat/satmanu/cms/racy/backgr.htm

http://www.netweather.tv/?action=jetstream;sess=

http://www.weeronline.nl/vakman-index/130/0

Edited December 4, 2013 by Vorticity0123

[Boro Snow]

Does that mean we'll have Sky News cameras at the ready like previous times?! 

hahahaha you no better than that 

[radiohead]

Look at those isobars on the 18Z NAE. What a storm for the North Sea. 80+mph sustained.

 

[Darren Bown]

Already a noticeable breeze picked up here over the last hour.

[R.P. McMurphy]

Worst east coast tidal surge in 30 years may be on the way according to the Environment Agency:

 

http://www.netweather.tv/index.cgi?action=news;storyid=5553;sess=

 

Yup, check out the predicted wind here: http://www.severe-weather-centre.co.uk/index.php?id=3268&L=0

 

It's not just the UK in the line either:

 

A developing extratropical low pressure system over the North Atlantic, dubbed "Xaver" by the Free University of Berlin, is predicted to "bomb" into a potent storm with winds near hurricane force that will bring damaging winds and storm tides to the coasts of Germany, the Netherlands, and Denmark on Thursday. The center of the low will pass over southern Norway, bringing strong northwest winds that will funnel down the North Sea. The European model predicts that at 18 UTC on Thursday, winds on the west coast of Denmark will be sustained near 69 mph (110 kph), and will be near 115 mph (185 kph) at 850 mb (roughly a height of 5,000 feet or 1500 meters). Xaver will be accompanied by intense thunderstorms capable of mixing the 850 mb winds down to the surface, and wind damage may rival that of October's Extratropical Storm "Christian" (AKA the St. Jude storm), which bottomed out at 968 mb. Christian killed 18, and did $1.4 billion in damage. There is a smaller chance that the wind damage from Xaver will approach that of Windstorm Anatol, which hit Denmark, Southwest Sweden, and Northern Germany on December 3, 1999. Anatol had sustained winds of up to 91 mph (146 kph), killed 20 people, and injured over 800. Damage was $2.6 billion (1999 dollars) in Denmark, making it the costliest disaster in Danish history

http://www.wunderground.com/blog/JeffMasters/show.html

 

 

Met Alarms: http://www.meteoalarm.eu/

Edited December 4, 2013 by Glenn W

[lorenzo]

Gusts approx 90mph into West Coast of Scotland. 

 

One of those situations where looking at the charts here before the event is nice, however the eery element remains that a system like this can catch folk out.

 

The introduction of the cold air is rapid.

 

6am - noon - 6 pm