Europe expected to see a large increase in Hurricane Sandy-like hybrid storms

By: Dr. Jeff Masters , 4:18 PM GMT on April 08, 2013

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Watch out, Europe. Dangerous part-hurricane, part extratropical hybrid storms like Hurricane Sandy of 2012 are expected to be an increasing threat for Western Europe by the end of the century due to global warming, said a team of scientists led by Reindert J. Haarsma of the Royal Netherlands Meteorological Institute. In a paper called "More hurricanes to hit Western Europe due to global warming", published in April 2013 in Geophysical Research Letters, the researchers describe the results from runs of a high-resolution (25 km grid spacing) climate model based on the European Centre for Medium Range Weather Forecasts (ECMWF) numerical weather prediction model. The model predicts that the breeding ground for Atlantic hurricanes will shift approximately 700 miles eastwards as the oceans warm this century. Hurricanes which form farther to the east can spend more time over warm tropical waters before turning north and northeast towards Europe, increasing the odds that these storms will have hurricane-force winds upon arrival in Europe. The model showed that wind shear will change little in the region over the coming decades, resulting in a large increase in storms with hurricane-force winds affecting Western Europe. Most of the these storms will not be tropical hurricanes upon arrival in Europe, but will be former hurricanes that have transitioned to extratropical storms. However, as we saw with Hurricane Sandy of 2012, these hybrid storms can be extremely dangerous. Summed over Norway, the North Sea, and the Gulf of Biscay, the model found that the number of hurricane-force storms in August - October increased from 2 to 13 over the 21st century, with almost all future West European hurricane-force storms predicted to originate as hurricanes or tropical storms in the tropics by 2100. The researchers conclude that "tropical cyclones will increase the probability of present-day extreme events over the North Sea and the Gulf of Biscay with a factor of 5 and 25 respectively, with far reaching consequences especially for coastal safety."


Figure 1. Hurricane Sandy at 10:10 am EDT October 28, 2012. Image credit: NASA/GSFC.

Europe's hurricane history
Only once since accurate records began in 1851 has an actual hurricane with full tropical characteristics hit Europe. This happened on September 16, 1961, when Category 1 Hurricane Debbie hit northwestern Ireland. Wind gusts reached 106 mph at Ballykelly and 104 mph at Tiree and Snaefill, and coastal radio stations reported the airwaves were jammed with calls for help from small ships and fishing craft. Eleven people were killed and 50 injured in the storm. The only other tropical cyclone recorded to have hit Europe since 1851 was Hurricane Vince of 2005, which hit southern Spain as a tropical depression on October 11, 2005. Historical documents also suggest a hurricane hit Spain on October 29, 1842.


Figure 2. Hurricane Debbie of 1961 was the only fully tropical hurricane ever recorded to hit Europe.

Britain's history of ex-hurricane strikes
Hurricanes that transition to powerful extratropical storms hit the British Isles several times per decade, on average. In 2011, Hurricane Katia brushed by Newfoundland, made the transition from a tropical system to a powerful extratropical storm, and maintained strong winds of 50 - 65 mph as it crossed the Atlantic. Ex-Katia hit northern Scotland on September 12, 2011. Glen Ogle, Scotland, at an elevation of 1500 feet (546 meters), received sustained winds of 60 mph, gusting to 86 mph. Cairngorm, in the Scottish Highlands at an elevation of 4085 feet, reported sustained winds of 67 mph. With the trees in full leaf, tree damage was much higher than a winter or springtime storm of similar ferocity would have caused. One person was killed by a falling tree, and heavy tree damage and numerous power failures were reported throughout Britain. Other gusts experienced in Britain included 76 mph at Edinburgh Blackford Hill, 75 mph at Capel Curig in Wales, 72 mph at Glasgow Bishopton, and 71 mph at Loftus, North Yorkshire.


Figure 3. Image of Hurricane Katia taken from the International Space Station at 15 GMT September 9, 2011, by astronaut Ron Garan. At the time, Katia was a Category 1 hurricane with 85 mph winds. Long Island, New York is visible at the lower left.


Figure 4. Surface wind estimate from the Windsat satellite at 4:04 am EDT on Monday, September 12, 2011. The center of Extratropical Storm Katia is marked by an "L", and winds in excess of 50 knots (58 mph, purple triangles) were occurring to the southwest of the center, near the west coast of Ireland. Image credit: NOAA.

As reported by UK Met Office forecaster John Hammond in a post on the BBC 23 degrees blog, Britain has been affected at least eight times in the past twenty years by extratropical storms that were once tropical storms or hurricanes. Before Katia of 2011, the most recent such storm was Hurricane Bill of 2009, which hit Ireland as an extratropical storm on August 25 with sustained winds of 45 mph. Bill was a Category 4 hurricane northeast of the Lesser Antilles five days prior. In 2006, a record three extratropical storms that had once been tropical cyclones hit Britain:

Extratropical Storm Alberto, which had been a strong tropical storm that hit the Florida Panhandle, hit northern Ireland and Scotland as an extratropical storm with 35 mph winds.

Extratropical Storm Gordon hit Ireland on September 21, 2006, with sustained winds of 65 mph. Gordon brought record warm temperatures as tropical air pushed north across the UK, and also strong winds that brought down power lines in Northern Ireland. Wind gusts to 60 mph (97 km/h) occurred in the Isles of Scilly off the southwest coast, and 81 mph (130 km/h) on the mainland.

Extratropical Storm Helene hit Northwestern Ireland on September 27, 2006, with sustained winds of 45 mph.

Figure 5. Path of Hurricane Lili of 1996, which caused $420 million in damage to the U.K. as an extratropical storm.

Other post-tropical cyclones that have the U.K. in the past twenty years include Hurricanes Isaac and Leslie of 2000, Hurricane Karl of 1998, and Hurricane Lili of 1996. The most severe of these storms was Extratropical Storm Lili, which hit Ireland on October 28, 1996, with sustained winds of 65 mph. Lili caused $420 million in damage (2011 dollars) in the U.K. According to Wikipedia, Lili produced a 92 mph (148 km/h) gust at Swansea, South Wales, while bringing a 4' (1.2 meter) storm surge that inundated the River Thames. In Somerset, 500 holiday cottages were severely damaged. A U.S. oil drilling platform, under tow in the North Sea, broke loose during the storm and nearly ran aground at Peterhead. On the Isle of Wight, a sailing boat was beached at Chale Bay; luckily all five occupants were rescued. It was the most damaging storm to have struck the United Kingdom since the Great Storm of 1987, which killed 22 and did $660 million in damage (1996 dollars.) However, Lili also broke a four-month drought over southwest England.

All but one of these storms hit during the peak part of hurricane season, mid-August - late October. The only exception was Ex-Tropical Storm Alberto of 2006, which hit Britain in June.


Figure 6. Hybrid subtropical storm of October 8, 1996, off the coast of Italy. According to Reale and Atlas (2001), the storm had characteristics similar to a hurricane, but formed over cool waters of 21.5°C (71°F.) They reported that "The maximum damage due to wind occurred over the Aeolian Islands, at 38.5°N, 15°E, to the northeast of Sicily: assistance for disaster relief was required. Unfortunately, no weather station data were available, but the media reported sheds, roofs and harbor devices destroyed, and houses and electric lines damaged, due to 'extremely strong westerly wind.' The perfect agreement between the observations at Ustica, the storm scale, the eye-like feature position and the damages over the Aeolian Island reasonably suggest that the hurricane-level intensity of 32 m/s (72 mph) was reached over the Aeolian Islands." A similar hybrid low affected Algeria on 9 - 10 November 2001. This storm produced upwards of 270 mm (10.6") of rain, winds of 33 m/s (74 mph), and killed 737 people near Algiers, mostly from flooding and mud slides. Image credit: Dundee satellite receiving station.

Hurricanes in the Mediterranean Sea?
The Mediterranean Sea between Europe and Africa has experienced several damaging hybrid subtropical storms in recent decades, but has never experienced a fully tropical hurricane in recorded history. However, global warming may cause the Mediterranean to start spawning hurricanes by 2100, according to a 2007 study by a research team led by Miguel Angel Gaertner of the University of Castilla-La Mancha in Toledo, Spain. They ran nine different climate models with resolutions of about 50 km and found that some (but not all) of the models simulated hurricanes in the Mediterranean in September by the end of the century, when ocean temperature could increase by 3°C, reaching 30°C.

Though the Mediterranean may start seeing hurricanes by the end of the century, these storms should be rare and relatively short-lived for three reasons:

1) The Mediterranean is quite far north and is subject to strong wind shear from jet stream activity.

2) The waters are shallow, and have relatively low heat content. There is no deep warm water current like the Gulf Stream.

3) The Mediterranean has a lot of large islands and peninsulas poking into it, increasing the chances that a tropical storm would weaken when it encountered land.

References
Gaertner, M. A., D. Jacob, V. Gil, M. Dominguez, E. Padorno, E. Sanchez, and M. Castro (2007), Tropical cyclones over the Mediterranean Sea in climate change simulations, Geophys. Res. Lett., 34, L14711, doi:10.1029/2007GL029977.

Haarsma et al., 2013, More hurricanes to hit Western Europe due to global warming, Geophysical Research Letters, DOI: 10.1002/grl.50360

Reale, O., and R. Atlas. 2001: Tropical Cyclone-Like Vortices in the Extratropics: Observational Evidence and Synoptic Analysis, Weather and Forecasting, 16, No. 1, pp. 7-34.

Jeff Masters

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Quoting TropicalAnalystwx13:
Man...it's going to be 28C (83F) tomorrow afternoon. It's going to take a while for me to adjust to these warmer temperatures, assuming they don't fluctuate too much over the next two weeks.

90 Degrees here today.
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Link
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Quoting trHUrrIXC5MMX:


yes
Woah! Almost April 10th, 2013 already. I forgot about Colorado State University's Hurricane Season 2013 prediction for about a month by now. I can't wait to see what they are predicting for this season.
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Man...it's going to be 28C (83F) tomorrow afternoon. It's going to take a while for me to adjust to these warmer temperatures, assuming they don't fluctuate too much over the next two weeks.
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Quoting GeoffreyWPB:


Wish you the best! I went through a triple-hernia ordeal. Missed three months of work and have permanent numbness in my legs.
That must really suck. I am really sorry you had to go through that:(.
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Quoting Levi32:
It's kind of trippy watching this powerful of a cold front advancing southeastward...without a closed parent low. 23z RAP analysis shows nice 850mb rotation in southern Kansas, but no pressure center. In a sense, this setup may actually be allowing a more direct and widespread overrunning event with warm, moist air charging directly into the long front.


No kidding. It's very rare to get such a warm, moist airmass running directly over such a cold one.







Isentropic lift at its best.
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It's kind of trippy watching this powerful of a cold front advancing southeastward...without a closed parent low. 23z RAP analysis shows nice 850mb rotation in southern Kansas, but no pressure center. In a sense, this setup may actually be allowing a more direct and widespread overrunning event with warm, moist air charging directly into the long front.

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Quoting Doppler22:
Has all of today's warnings been in the Cold air areas with sleet and snow falling?

As far as I'm aware. A strong cap is in place across much of the environment ahead of the front. Any cell that has attempted to develop has quickly dissipated.
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Has all of today's warnings been in the Cold air areas with sleet and snow falling?
Member Since: February 13, 2012 Posts: 11 Comments: 3821
Hey guys. Posted my New April Outlook late last night, so for you guys that went to bed earlier... Here you go.

2013 Hurricane Season : April Outlook
Member Since: October 3, 2010 Posts: 40 Comments: 4129
Quoting PalmBeachWeather:
I hear ya hydrus..Ohio for me.......You??
South Florida.
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Some of these storms are really moving.

SEVERE WEATHER STATEMENT
NATIONAL WEATHER SERVICE OMAHA/VALLEY NEBRASKA
703 PM CDT TUE APR 9 2013

NEC021-039-053-100030-
/O.CON.KOAX.SV.W.0017.000000T0000Z-130410T0030Z/
BURT NE-CUMING NE-DODGE NE-
703 PM CDT TUE APR 9 2013

...A SEVERE THUNDERSTORM WARNING REMAINS IN EFFECT UNTIL 730 PM CDT
FOR NORTHWESTERN BURT...SOUTHEASTERN CUMING AND NORTHWESTERN DODGE
COUNTIES...

AT 656 PM CDT...A SEVERE THUNDERSTORM WAS LOCATED NEAR SCRIBNER...OR
37 MILES NORTHEAST OF COLUMBUS...MOVING NORTH AT 70 MPH.

HAZARD...QUARTER SIZE HAIL.

SOURCE...TRAINED WEATHER SPOTTERS. AT 655 PM...1 INCH HAIL WAS
REPORTED 3 MILES NORTHWEST OF NORTH BEND.

IMPACT...DAMAGE TO VEHICLES AND CROPS IS EXPECTED.

LOCATIONS IMPACTED INCLUDE...
WEST POINT...SCRIBNER AND SNYDER.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

THIS STORM IS PRODUCING LARGE HAIL. SEEK SHELTER NOW INSIDE A STURDY
STRUCTURE AND STAY AWAY FROM WINDOWS.

&&

LAT...LON 4197 9647 4148 9668 4154 9687 4201 9668
4201 9658
TIME...MOT...LOC 2355Z 198DEG 60KT 4169 9672

HAIL...1.00IN
WIND...<50MPH

$$

NIETFELD
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See these storms with Severe Thunderstorm Warnings?



Well, surface obs indicate that snow is falling in those storms!

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Quoting aspectre:

The lab hands down.
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The snow machine is getting ready to kick into gear.



MESOSCALE DISCUSSION 0413
NWS STORM PREDICTION CENTER NORMAN OK
0646 PM CDT TUE APR 09 2013

AREAS AFFECTED...FAR NERN CO...WRN AND N-CNTRL NEB...ERN
WY...SWRN/S-CNTRL SD

CONCERNING...HEAVY SNOW

VALID 092346Z - 100445Z

SUMMARY...HEAVY SNOWFALL WITH RATES EXCEEDING 1-2 IN/HR WILL BE
POSSIBLE TONIGHT...INITIATING FIRST OVER FAR NERN CO...WRN NEB...ERN
WY AND SWRN SD THIS EVENING. HEAVY SNOWFALL WILL THEN EXPAND NEWD
ACROSS N-CNTRL NEB AND MUCH OF S-CNTRL SD LATER TONIGHT. IN
ADDITION...ISOLATED CONVECTIVE ELEMENTS MAY PRODUCE SOME SLEET.

DISCUSSION...LATEST WV IMAGERY SHOWS AN EMBEDDED SHORTWAVE TROUGH
PIVOTING N-NEWD INTO ERN CO AROUND AN UPPER TROUGH CENTERED OVER THE
FOUR CORNERS REGION. THE UPPER IMPULSE OVER ERN CO IS FORECAST TO
EJECT NEWD INTO KS THIS EVENING...AND THEN WRN/CNTRL NEB BY O6Z.
MODERATE TO STRONG DEEP-LAYER ASCENT WILL AID IN AN EXPANDING SHIELD
OF PRECIPITATION DEVELOPING OVER FAR NERN CO...WRN NEB...ERN WY AND
SWRN SD THIS EVENING...WHICH WILL THEN SPREAD INTO N-CNTRL NEB AND
S-CNTRL SD TONIGHT. MODEL FORECAST SOUNDINGS SHOW THE PRESENCE OF
ELEVATED CAPE ROOTED ABOVE 700 MB...WHICH WILL SUPPORT ENHANCED
PRECIPITATION RATES. THIS INSTABILITY COMBINED WITH MODERATE/STRONG
ASCENT...SUB-FREEZING FORECAST SOUNDINGS...AND INCREASINGLY
SATURATED THERMODYNAMIC PROFILES SUGGEST SNOWFALL RATES AOA 1-2
IN/HR WILL BE POSSIBLE.

..GARNER.. 04/09/2013


ATTN...WFO...FSD...ABR...LBF...UNR...BOU...CYS...

LAT...LON 43059837 41989953 40850176 40750312 41030412 41550469
42850493 44070409 44680252 44769924 44169823 43059837
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Quoting Tornado6042008X:
Good evening bloggers!! I just found out that I have hernia and will have to have surgery done very soon. So yay me! Anyway there are a lot of severe thunderstorms in Eastern Nebraska and East Kansas right now, even some snow thunderstorms in SW Kansas, the eastern Oklahoma panhandle, and the NE Texas panhandle. Very interesting indeed.


Wish you the best! I went through a triple-hernia ordeal. Missed three months of work and have permanent numbness in my legs.
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Though I've read many many stories about dogs swimming ashore after their owners drown trying to rescue them, I've yet to come across one in which the dog drowns.
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Good evening bloggers!! I just found out that I have hernia and will have to have surgery done very soon. So yay me! Anyway there are a lot of severe thunderstorms in Eastern Nebraska and East Kansas right now, even some snow thunderstorms in SW Kansas, the eastern Oklahoma panhandle, and the NE Texas panhandle. Very interesting indeed.
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LOL. That was a mess. Let me try again.

Add: Nvmd. I give.
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Member Since: April 23, 2011 Posts: 104 Comments: 14873
Tropical Storm Victoria in the Australia/Fiji region has quickly become as intense -- if not even stronger, unofficially -- than Tropical Storm Imelda. Conventional and microwave satellite imagery reveals the development of a very small, and probably unstable, eye in association with the storm.

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Miami NWS Disco

.LONG TERM (FRIDAY THROUGH TUESDAY)...
THE EXTENDED PORTION OF THE FORECAST IS BECOMING A LITTLE MORE
CERTAIN WITH BOTH THE GFS AND ECMWF IN BETTER AGREEMENT TO THE
SYNOPTIC PATTERN. BOTH MODELS NOW ARE INDICATING THE MAIN TROUGH
WELL TO OUR NORTH WITH THE FRONT LACKING THE PUSH AND STALLING IT
NEAR THE LAKE OR SLIGHTLY TO THE NORTH. THIS WILL PLACE SOUTH
FLORIDA IN THE WARM SECTOR WITH ENOUGH INSTABILITY FOR THE
POSSIBILITY OF THUNDER EACH DAY BEGINNING ON FRIDAY AND THROUGH THE
WEEKEND. ANOTHER FACTOR TO CONSIDER IS THAT THE MODELS ALSO ARE
SHOWING A SOUTHERN STREAM MID LEVEL TROUGH MOVING OUT OF THE DESERT
SOUTHWEST ACROSS THE GULF COAST INTO THE SOUTHEAST STATES LATE IN
THE WEEKEND AND EARLY NEXT WEEK. DEPENDING ON THE PROXIMITY OF THIS
TROUGH THIS COULD ENHANCE CONVECTIVE ACTIVITY FOR SOUTH FLORIDA LATE
IN THE PERIOD.

For West Palm Beach...

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Quoting Levi32:
I have to say, this looks so awesome in eastern Nebraska: deep convection with -70C cloud tops over sub-freezing surface temperatures. The sounding shows major overrunning of the warm air mass. Multiple reports of freezing rain are showing up in the obs.





Those steep lapse rates in the mid levels. The elevated convection is taking full advantage of that, which can be seen on the 500 mb vertical velocity.

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Sorry TA, I didn't see post 817 before I posted about Nebraska lol.
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WOCN11 CWTO 092139
Special weather statement updated by Environment Canada
EDT Tuesday 9 April 2013.
------------------------------------------------- --------------------
Special weather statement for:
=new= Belleville - Quinte - Northumberland
=new= Kingston - Prince Edward
=new= Peterborough - Kawartha Lakes
=new= Stirling - Tweed - South Frontenac
=new= Bancroft - Bon Echo Park
=new= Brockville - Leeds and Grenville
=new= City of Ottawa
=new= Gatineau
=new= Prescott and Russell
=new= Cornwall - Morrisburg
=new= Smiths Falls - Lanark - Sharbot Lake
=new= Parry Sound - Muskoka
=new= Haliburton
=new= Renfrew - Pembroke - Barry's Bay
=new= Algonquin
=new= Burk's Falls - Bayfield Inlet
City of Toronto
Windsor - Essex - Chatham-Kent
Sarnia - Lambton
Elgin
London - Middlesex
Simcoe - Delhi - Norfolk
Dunnville - Caledonia - Haldimand
Oxford - Brant
Niagara
City of Hamilton
Halton - Peel
York - Durham
Huron - Perth
Waterloo - Wellington
Dufferin - Innisfil
Grey - Bruce
Barrie - Orillia - Midland.

Rainy over most of Southern Ontario through Wednesday.
Freezing rain and ice pellets over South Central Ontario
Thursday. Significant snowfall over northern and eastern
Sections Friday.

------------------------------------------------- --------------------
==discussion==
A series of frontal waves is giving a wet week to portions of
Southern Ontario. Rainfall warnings are currently in effect for much
of Southwestern Ontario with rain at times heavy expected to continue
through Wednesday.

On Thursday, significant ice pellets and freezing rain are forecast
to affect an area from Southern Lake Huron to Western Lake Ontario,
including the Toronto area.

On Friday, the system will spread northeastward to affect northern
and eastern sections, including the Ottawa area, likely giving a
significant snowfall. Ice pellets will be possible near the St
Lawrence River.

Environment Canada is watching the development of this situation
closely and will issue further statements and warnings if required.

Please monitor the latest forecasts and warnings from Environment
Canada at www.weatheroffice.gc.ca.

End
Member Since: July 15, 2006 Posts: 175 Comments: 54858
I have to say, this looks so awesome in eastern Nebraska: deep convection with -70C cloud tops over sub-freezing surface temperatures. The sounding shows major overrunning of the warm air mass. Multiple reports of freezing rain are showing up in the obs. Notice the wind shift from north in the low-levels to southerly higher up. Amazing.




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Member Since: July 15, 2006 Posts: 175 Comments: 54858
Not too often you can distinctly see a cold front on water vapor imagery.

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Quoting stormchaser19:
Anybody know if tomorrow is the April CSU Hurricane Season outlook?


yes
Member Since: April 23, 2011 Posts: 104 Comments: 14873
now this is getting retarded here



Rainfall warning in red

Winter storm watch yellow

Winter storm watch for
City of Toronto issued

Ice pellets and freezing rain likely Thursday.

A series of low pressure systems will give periods of rain to the regions into Wednesday night. On Thursday, a stronger low will arrive from the southwest and combine with a colder airmass from the north. As a result rain is expected to change to ice pellets and freezing rain Thursday morning. The ice pellets and freezing rain are expected to persist through Thursday night and be heavy at times.

Poor travel conditions are expected Thursday. In some places, power outages may occur. Conditions are expected to improve Friday.

There is still some uncertainty as to the track of the storm and the extent of the cold air Thursday. Environment Canada will monitor this situation closely and will issue warnings as needed as the track of the storm becomes more certain.

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Quoting stormchaser19:
Anybody know if tomorrow is the April CSU Hurricane Season outlook?


I think tomorrow
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821. beell
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820. wxmod
Ship pollution today, Pacific near CA. MODIS satellite photo.

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Long time since I read that page, but this line seems important.

"Obviously it is not the high moisture content that is responsible for a threat for storms at Cheyenne."
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Strange day for storms today...

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In case you were wondering the technical reasons for the snow-thunderstorms across Nebraska...

A look at recent skew-t's from across eastern Nebraska show a very pronounced cold atmosphere at the lower-levels of the atmosphere, which is to be expected given that these locations are on the backside of the powerhouse cold front. A few thousand feet up, however, temperatures dramatically increase, even as much as 15-20C. This creates elevated instability -- meaning it's not at the surface level -- which allows elevated thunderstorms to form. The hail falls and naturally doesn't melt given the cold environment, while the frozen precipitation -- sleet, freezing rain, etc -- continues to form and glaze everything at the surface.

I've seen this on occasion, but not to this extent.

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Quoting stormchaser19:
Anybody know if tomorrow is the April CSU Hurricane Season outlook?


Yes, around 10:00 AM EDT.
Member Since: April 29, 2009 Posts: 75 Comments: 14574
Quoting bappit:
@811 The answer to your mystery may be here, Potential Temperature and Mixing Ratio--Contributions to Theta-e on Elevated Terrain .

"As experienced storm chasers are well aware, severe thunderstorms occur on the high plains with much lower surface dewpoint temperatures than at low elevations."



Ha its interesting that you post that because I've read through that page quite a bit, its a great one :)

Keep in mind though, that's referring to surface dew points over higher terrain, not total Precipitable water. If it was around 1 inch to 1.2 that would make sense, that is plenty sufficient in those regions for April. However 0.5 to 0.8 inch PWAT is really low, in fact here the NWS would probably refer to it as desert air. To see moisture levels that low even in winter is approaching the record minimum in atmospheric moisture in this area.

Now, I know that you would need less moisture in those regions than in the Deep South and Florida as apposed to the middle plains in April, but still, it seems strangely low even in this region to support the vigorous healthy thunderstorms that are there. You would think some steady light rain with maybe some small hail would be more common.
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814. beell
Quoting Barefootontherocks:
Breakin' the cap in SW OK and N TX.





And that ole north wind right behind.

Frederick, OK VAD

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Anybody know if tomorrow is the April CSU Hurricane Season outlook?
Member Since: June 20, 2012 Posts: 0 Comments: 2169
@811 The answer to your mystery may be here, Potential Temperature and Mixing Ratio--Contributions to Theta-e on Elevated Terrain .

"As experienced storm chasers are well aware, severe thunderstorms occur on the high plains with much lower surface dewpoint temperatures than at low elevations."

The overrunning would be similar to rising over terrain.
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Its strange to me to see strong thunderstorms breaking out across parts of the mid and upper plains in a region that has a PW of 0.5 to 0.8, that is really dry air and hostile to precip.
The thunderstorms feeding off elevated instability above cold surface air makes sense, that is a typical overrunning event. Although the thunderstorms forming in such dry atmospheric conditions is what is perplexing to me, its amazing they are producing any precip making it to the surface, they must be very efficient.
Member Since: August 21, 2008 Posts: 0 Comments: 7834
I'm guessing the showers near Houston are under the cap. Humid air coming off the Gulf.
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Member Since: July 15, 2006 Posts: 175 Comments: 54858
Breakin' the cap in SW OK and N TX.



(Changed to "." then restored original comment at 2042 cdt)
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Member Since: July 15, 2006 Posts: 175 Comments: 54858
Quoting PalmBeachWeather:
I tried....Rooster???

Beats me. He made so many.

Edit: would'n ja know. His given name was Marion Morrison.

The movie was Red River, 1948.
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URGENT - IMMEDIATE BROADCAST REQUESTED
SEVERE THUNDERSTORM WATCH NUMBER 86
NWS STORM PREDICTION CENTER NORMAN OK
535 PM CDT TUE APR 9 2013

THE NWS STORM PREDICTION CENTER HAS ISSUED A
SEVERE THUNDERSTORM WATCH FOR PORTIONS OF

CENTRAL KANSAS
CENTRAL AND WESTERN OKLAHOMA
WESTERN NORTH TEXAS

EFFECTIVE THIS TUESDAY AFTERNOON AND WEDNESDAY MORNING FROM 535
PM UNTIL 100 AM CDT.

HAIL TO 2 INCHES IN DIAMETER...THUNDERSTORM WIND GUSTS TO 70
MPH...AND DANGEROUS LIGHTNING ARE POSSIBLE IN THESE AREAS.

THE SEVERE THUNDERSTORM WATCH AREA IS APPROXIMATELY ALONG AND 75
STATUTE MILES EAST AND WEST OF A LINE FROM 35 MILES SOUTH
SOUTHWEST OF WICHITA FALLS TEXAS TO 45 MILES NORTH OF HUTCHINSON
KANSAS. FOR A COMPLETE DEPICTION OF THE WATCH SEE THE ASSOCIATED
WATCH OUTLINE UPDATE (WOUS64 KWNS WOU6).

REMEMBER...A SEVERE THUNDERSTORM WATCH MEANS CONDITIONS ARE
FAVORABLE FOR SEVERE THUNDERSTORMS IN AND CLOSE TO THE WATCH
AREA. PERSONS IN THESE AREAS SHOULD BE ON THE LOOKOUT FOR
THREATENING WEATHER CONDITIONS AND LISTEN FOR LATER STATEMENTS
AND POSSIBLE WARNINGS. SEVERE THUNDERSTORMS CAN AND OCCASIONALLY
DO PRODUCE TORNADOES.

DISCUSSION...SCATTERED THUNDERSTORMS ARE EXPECTED TO INTENSIFY THIS
AFTERNOON AND EVENING OVER THE WATCH AREA. STORMS WILL BE BEHIND A
STRONG SURFACE COLD FRONT. BUT DESPITE THE VERY COLD LOW LEVEL
ENVIRONMENT...FORECAST SOUNDINGS SHOW AMPLE ELEVATED INSTABILITY AND
SHEAR FOR ROTATING THUNDERSTORMS CAPABLE OF LARGE HAIL.
COVERAGE OF
STORMS MAY CONTINUE TO INCREASE THROUGH MIDNIGHT.

AVIATION...A FEW SEVERE THUNDERSTORMS WITH HAIL SURFACE AND ALOFT
TO 2 INCHES. EXTREME TURBULENCE AND SURFACE WIND GUSTS TO 60
KNOTS. A FEW CUMULONIMBI WITH MAXIMUM TOPS TO 500. MEAN STORM
MOTION VECTOR 23035.
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Quoting bappit:
Different movie but same dude. :)
I tried....Rooster???
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About

Jeff co-founded the Weather Underground in 1995 while working on his Ph.D. He flew with the NOAA Hurricane Hunters from 1986-1990.