Virtual storm chase

**Nick F** · March 27, 2007

Some rather tasty looking storms over SW Arkansas and NW Louisiana this afternoon over there, not sure what the terrain's like in that area for chasing, but some tornado warnings in force:

urgent - immediate broadcast requested

Tornado Watch number 78

NWS Storm Prediction Center Norman OK

1235 PM CDT Tue Mar 27 2007

The NWS Storm Prediction Center has issued a

Tornado Watch for portions of

southwest and south central Arkansas

northwest Louisiana

extreme northeast Texas

Effective this Tuesday afternoon and evening from 1235 PM until

800 PM CDT.

Tornadoes... hail to 1.5 inches in diameter... thunderstorm wind

gusts to 70 mph... and dangerous lightning are possible in these

areas.

The Tornado Watch area is approximately along and 95 statute

miles north and south of a line from 40 miles northwest of

Shreveport Louisiana to 50 miles east northeast of El Dorado

Arkansas. For a complete depiction of the watch see the

associated watch outline update (wous64 kwns wou8).

Remember... a Tornado Watch means conditions are favorable for

tornadoes and 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.

Discussion... a cluster of tstms has shown embedded supercell

structures across extreme NE TX during the past hour... while other

storms are forming in a separate cluster in SW AR. The shv vwp

reveals a narrow corridor with favorable vertical shear for

supercells... and it appears there is some organization to the storm

clusters on the mesoscale. With gradual destabilization continuing

across AR/nrn la in advance of the storms... there is the potential

for the isolated tornado and damaging wind/hail threat to persist

through the afternoon across NW la into SW AR. Additionally... more

isolated tstms will develop across E TX and spread newd into wrn la

along the instability axis. The primary threat with these storms

will be isolated large hail and damaging gusts.

Aviation... tornadoes and a few severe thunderstorms with hail

surface and aloft to 1.5 inches. Extreme turbulence and surface

wind gusts to 60 knots. A few cumulonimbi with maximum tops to

500. Mean storm motion vector 24025.

... A Tornado Warning remains in effect until 445 PM CDT for Union

County...

At 356 PM CDT... National Weather Service Doppler radar continued to

indicate a tornado. This tornado was located 10 miles west of

strong... or about 12 miles east of Junction City... moving northeast

at 30 mph.

The tornado will be near...

4 miles northwest of strong by 410 PM CDT

The rotation in this storm has been weakening over the last few

minutes... but could strengthen again as it moves across the eastern

sections of Union County.

Another strong thunderstorm showing weak rotation was indicated over

the northern sections of El Dorado. Another strong thunderstorms was

also indicated along Highway 15 just southwest of the Three Creeks

community in southwest Union County. Gusty winds to 45 mph and pea

sized hail will be possible with this storm.

Paul Sherman · March 28, 2007

Quite a Day setting up for tomorrow in most of the Plains, have been looking at all the Models and Hodographs etc and I am fully expecting the SPC To upgrade to a MODERATE Tomorrow, 2 prime areas for chasing look likely. The most favoured is into Nebraska and N Central NW Kansas where Tornadoes look VERY Likely given the current models, My Chase Target would be along I80 Near to Lexington, good road options all around there to catch the Mad storms flying out of Kansas. 2nd choice would be to play the Dryline in W Oklahoma and Western Kansas, these storms should be more Scattered and Slower moving to the North East, and any that root themselves could produce Tornadoes as well, gagging to get out there at the mo, and given this is looking more like a Late April and Early May chase I really am hoping the Seasons are not running about 45 days ahead like the Uk.
Paul Sherman

**Id expect quite a Large area to be upgraded to Moderate

Ahem, Cough Splutter, Good to see my reading of Models is not completely Wasted.

As predicted yesterday morning a Moderate Risk issued and quite a noteworthy Tornado Day could be on the cards.

Also worth noting if you could draw a Moderate Risk on the Map for Storm Chasers Nirvana (Eg Best Chase Country) that would be exactly where the Mod Box would be

Paul S

Gorky · March 28, 2007

Put me down for playing the southern part of the dryline here. I think the biggest tornado threat will be up into Nebraska but I worry about the storms staying discrete for any length of time. I think there may be fewer tornadoes south but possibly stronger and longer tracked. Would be sacrificing beter shear for better instability and I think it may jsut apy off. Targetting Woodward, Oklahoma (It seems that place comes up as a possible start location every time there is severe threat in the Mid West. Maybe we should book somewhere there in advance for the real Chase;))

Paul Sherman · March 28, 2007

:lol: About Woodward Nathan, just ask Stevestorms about Woodward, he has the freedom of the city!! I am starting in Hayes (Kansas) today as i dont want to be too far North in Nebraska, but again that lovely long trailing dryline is too good an opportunity too miss and you know how much I love Dryline Storms !!!

Paul S

Paul Sherman · March 28, 2007

Okay only 3-6 hours away from what could be a Widespread event, not only are their possibilities of Long Track Damaging Tornadoes but this will be followed by a Possibly Severe MCS Overnight :lol: Aaaah Heaven

DAY 1 CONVECTIVE OUTLOOK

NWS STORM PREDICTION CENTER NORMAN OK

0740 AM CDT WED MAR 28 2007

VALID 281300Z - 291200Z

...THERE IS A MDT RISK OF SVR TSTMS OVER PARTS OF NWRN TX...ERN TX

PANHANDLE...WRN OK...WRN/CENTRAL KS...SWRN/CENTRAL NEB...

...THERE IS A SLGT RISK OF SVR TSTMS FROM THE TX BIG BEND/SWRN TX

NWD ACROSS MUCH OF THE SRN AND CENTRAL PLAINS INTO SD AND FAR ERN

WY...

...THERE IS A SLGT RISK OF SVR TSTMS FROM THE CENTRAL APPALACHIANS

INTO PART OF THE CAROLINAS...

...WIDESPREAD SEVERE THUNDERSTORMS INCLUDING DAMAGING WINDS...VERY

LARGE HAIL AND POSSIBLY STRONG TORNADOES WILL DEVELOP OVER THE

WESTERN HALF OF THE CENTRAL AND SOUTHERN PLAINS LATER TODAY AND

TONIGHT...

...CENTRAL/SRN PLAINS...

STRONG UPPER LOW WILL SHIFT INTO THE CENTRAL ROCKIES AND THEN REMAIN

STATIONARY OVERNIGHT. AS THIS OCCURS...SURFACE DRY LINE WILL BECOME

WELL ESTABLISHED OVER THE HIGH PLAINS AND LIKELY EXTEND FROM A LOW

OVER FAR NERN CO SWD JUST EAST OF THE KS/CO BORDER INTO THE CENTRAL

TX PANHANDLE AND FAR SWRN TX BY EARLY THIS EVENING. THOUGH SMALL

SCALE DETAILS ARE DIFFERENT...OPERATIONAL MODELS ALONG WITH SREF AND

HIGH-RESOLUTION WRFS ARE ALL IN AGREEMENT IN WIDESPREAD THUNDERSTORM

DEVELOPMENT OVER WRN PARTS OF THIS REGION LATER TODAY AND

TONIGHT...WITH HIGH LIKELIHOOD OF SEVERE WEATHER/SUPERCELLS.

IMPRESSIVE EML EVIDENT ON MORNING SOUNDINGS SUGGEST AIR MASS WILL

BECOME VERY UNSTABLE OVER WRN HALF OF THE SRN PLAINS BY LATER

TODAY...WITH MODERATE INSTABILITY DEVELOPING NWD INTO WRN NEB.

MLCAPE IN EXCESS OF 2000 J/KG IS FORECAST BY NEARLY ALL MODELS JUST

EAST OF DRY LINE INTO WRN KS...WITH AXIS OF NEARLY 1000 J/KG MLCAPE

NOSING NNWWD TOWARDS NWRN NEB. LOW AND DEEP LAYER SHEAR WILL BE

SIGNIFICANT ALONG THE WRN PLAINS DESPITE STRONGEST MID LEVEL JET

EXTENDING NNEWD BEHIND THE DRY LINE OVER ERN CO. AS IS NORMALLY THE

CASE...COMPLEXITIES REMAIN REGARDING EXACT LOCATION AND TIMING OF

INITIATION AND IN OVERALL MODE OF STORM-SCALE ORGANIZATION. CAPPING

EVIDENT ON MORNING SOUNDINGS WILL AID IN NNWWD LOW LEVEL MOISTURE

RETURN AND RETARD DEEP CONVECTIVE DEVELOPMENT FOR MUCH OF THE

DAY...ESPECIALLY WITH LOW CLOUDS AND STRATUS THROUGH THE MORNING.

OVERNIGHT NAM AND GFS WERE BOTH SEVERAL DEGREES TOO COOL AT H85 AND

FAIL TO ACCURATELY DEPICT CAP AT AMA ACCORDING TO THE 12Z SOUNDING.

HOWEVER...BOTH DID WELL AT DDC AND NAM-KF WAS ACCURATE AT AMA AND

DDC.

STRONGEST ASCENT AND MODEST HEATING SHOULD SUPPORT INITIAL

DEVELOPMENT INTO WRN NEB AND NWRN KS BY LATE THIS AFTERNOON ALONG

NOSE OF 90+ KT H5 JET. MODELS SUGGESTING RAPID THUNDERSTORM

DEVELOPMENT WITHIN BROAD AREA OF UPPER DIFFLUENCE JUST EAST OF THE

DRY LINE INTO WRN KS AND THE TX PANHANDLE/WRN TX BETWEEN 21-00Z AS

CAP WEAKENS. HOW LONG ACTIVITY REMAINS IN THE FORM OF DISCRETE

SUPERCELLS REMAINS HARD TO SAY ATTM...AS ACTIVITY WILL LIKELY EVOLVE

INTO LINEAR STRUCTURES AS IT EVOLVES ENEWD THROUGH THE EVENING.

HOWEVER...VERY STEEP LAPSE RATES AND SHEAR WILL ENHANCE THE

POTENTIAL FOR SIGNIFICANT/DAMAGING HAIL AND STRONG TORNADOES INTO

THE EARLY-MID EVENING WITH DISCRETE STORMS. WIND DAMAGE THREAT

SHOULD ALSO INCREASE AS LINEAR ORGANIZATION BECOME MORE PREDOMINANT

THIS EVENING. LACK OF EWD PROGRESSION WITH OVERALL SYSTEM AND

NARROW INSTABILITY AXIS...SUGGEST STORMS SHOULD WEAKEN AS THEY MOVE

ACROSS CENTRAL SD/NE/KS/OK LATER THIS EVENING.

NAM AND GFS ARE ALSO INDICATING SECONDARY LOBE OF ENERGY ROTATING

AROUND LARGE UPPER LOW AND INTO THE NERN NM/SERN CO LATE TONIGHT.

THIS SHOULD SUPPORT DEVELOPMENT OF ANOTHER MCS...POSSIBLY

SEVERE...OVER WRN TX INTO WRN OK/SWRN KS OVERNIGHT

Paul Sherman

Gorky · March 28, 2007

I've had time too examine today, and I'm happy that the SPC have shifted the fatter portion of the tornado warning area from the north end to the southern end of the risk. I think I'm in the right area roughly, but probably should be positioned further west, into the Texas panhandle. To be honest, I don't think you can be in the wrong area if you are anywhere in that moderate risk... Severe threat should be pretty widespread today.

Edited March 28, 2007 by Gorky

**Nick F** · March 28, 2007

Yes I agree that the Moderate risk area should be shifted slightly further West perhaps spilling over the into far E Colorado and far E New Mexico, a look at Water Vapour imagery suggests the dry line (dark area/white area boundary) is roughly along the Eastern borders of New Mexico and Colorado and this is where the storms are likely to intiate over the next few hours and slowly shift NE, far South-West of Kansas or the Texas/Oklahoma pan handle would be my spot to chase:

WV imagery:

Left exit of Strong jet streak over the main risk area should provide strong PVA and lift aloft of warm moist air as the dry line runs through -also the resultant strong speed shear will allow supercells to form and entrained dry air should allow large hail:

I'm going for Elkhart in SW Kansas for my target area for severe weather and tornadoes, pretty much where I think the area will be of maximum convection along the dry line in 3-4 hrs looking at CAPE charts and significant tornado parameters (stp)- rather than further East in the SPC Moderate risk area.

**Nick F** · March 28, 2007

PDS (Particularly Dangerous Situation) Tornado Watch in force for Panhandle area:

http://www.spc.noaa.gov/products/watch/ww0082.html

Tornado watch:

THE NWS STORM PREDICTION CENTER HAS ISSUED A

TORNADO WATCH FOR PORTIONS OF

THE WESTERN OKLAHOMA PANHANDLE

THE TEXAS PANHANDLE AND THE SOUTH PLAINS OF WEST TEXAS

EFFECTIVE THIS WEDNESDAY AFTERNOON FROM 315 PM UNTIL MIDNIGHT CDT.

..THIS IS A PARTICULARLY DANGEROUS SITUATION

DESTRUCTIVE TORNADOES...LARGE HAIL TO 3 INCHES IN DIAMETER...

THUNDERSTORM WIND GUSTS TO 70 MPH...AND DANGEROUS LIGHTNING ARE

POSSIBLE IN THESE AREAS.

THE TORNADO WATCH AREA IS APPROXIMATELY ALONG AND 80 STATUTE

MILES EAST AND WEST OF A LINE FROM 20 MILES NORTH OF GUYMON

OKLAHOMA TO 50 MILES SOUTH SOUTHEAST OF LUBBOCK TEXAS. FOR A

COMPLETE DEPICTION OF THE WATCH SEE THE ASSOCIATED WATCH OUTLINE

UPDATE (WOUS64 KWNS WOU2).

REMEMBER...A TORNADO WATCH MEANS CONDITIONS ARE FAVORABLE FOR

TORNADOES AND 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.

OTHER WATCH INFORMATION...CONTINUE...WW 80...WW 81...

DISCUSSION...THE LOW LEVELS CONTINUE TO MOISTEN AS BOUNDARY LAYER

DEWPOINTS OF 60-64 F SPREAD NWD/NWWD ON STRENGTHENING LOW-LEVEL

FLOW. ALSO...SURFACE TEMPERATURES HAVE WARMED INTO THE 70S ACROSS

MUCH OF THE AREA...RESULTING IN WEAKENING CONVECTIVE INHIBITION.

THE DRYLINE IS BECOMING BETTER DEFINED NEAR THE TX/NM BORDER...AND

SHOULD PROVIDE A FOCUS FOR CONVECTIVE INITIATION IN THE NEXT COUPLE

OF HOURS. ALSO...A SUBTLE MID-UPPER SHORTWAVE TROUGH IS ROTATING

NEWD TOWARD W/NW TX...AND AT LEAST ISOLATED STORM DEVELOPMENT IS

POSSIBLE THIS AFTERNOON INVOF THE E CENTRAL AND SE TX PANHANDLE.

GIVEN THE INCREASING LOW-LEVEL MOISTURE AND STRENGTHENING WIND

FIELDS IN AREA PROFILERS AND VWP/S...AS WELL AS SHORT TERM MODEL

FORECASTS...THE ENVIRONMENT WILL BECOME INCREASINGLY FAVORABLE FOR

SUPERCELLS THROUGH THE AFTERNOON/EVENING. THE INITIAL ACTIVITY

SHOULD BE DISCRETE SUPERCELLS WITH THE POTENTIAL FOR A FEW STRONG

TORNADOES AND VERY LARGE HAIL. BY EARLY TONIGHT...CONVECTION MAY

GROW UPSCALE INTO ONE OR MORE LINE SEGMENTS WITH MORE OF A LARGE

HAIL AND DAMAGING WIND THREAT.

AVIATION...TORNADOES AND A FEW SEVERE THUNDERSTORMS WITH HAIL

SURFACE AND ALOFT TO 3 INCHES. EXTREME TURBULENCE AND SURFACE

WIND GUSTS TO 60 KNOTS. A FEW CUMULONIMBI WITH MAXIMUM TOPS TO

500. MEAN STORM MOTION VECTOR 24035.

Paul Sherman · March 28, 2007

Nick,

You dont get too many of those Jeez. Fully expecting a PDS For Western Kansas pretty soon, she is about to go bang out there, could be literally anywhere, most places reported CU Fields, there are going to be some Significant Tornadoes Today, let the fun begin and Potty we will need those Cams today for sure.

Paul S

Paul Sherman · March 28, 2007

And the Treble, this one for most of Kansas. And some Storms have just started firing South West of Dodge City. Let the games begin

URGENT - IMMEDIATE BROADCAST REQUESTED

TORNADO WATCH NUMBER 83

NWS STORM PREDICTION CENTER NORMAN OK

400 PM CDT WED MAR 28 2007

THE NWS STORM PREDICTION CENTER HAS ISSUED A

TORNADO WATCH FOR PORTIONS OF

WESTERN KANSAS

EXTREME SOUTHWEST NEBRASKA

EFFECTIVE THIS WEDNESDAY AFTERNOON FROM 400 PM UNTIL MIDNIGHT CDT.

TORNADOES...HAIL TO 3 INCHES IN DIAMETER...THUNDERSTORM WIND

GUSTS TO 70 MPH...AND DANGEROUS LIGHTNING ARE POSSIBLE IN THESE

AREAS.

THE TORNADO WATCH AREA IS APPROXIMATELY ALONG AND 65 STATUTE

MILES EAST AND WEST OF A LINE FROM 15 MILES NORTHWEST OF MCCOOK

NEBRASKA TO 5 MILES EAST SOUTHEAST OF LIBERAL KANSAS. FOR A

COMPLETE DEPICTION OF THE WATCH SEE THE ASSOCIATED WATCH OUTLINE

UPDATE (WOUS64 KWNS WOU3).

REMEMBER...A TORNADO WATCH MEANS CONDITIONS ARE FAVORABLE FOR

TORNADOES AND 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.

OTHER WATCH INFORMATION...CONTINUE...WW 80...WW 81...WW 82...

DISCUSSION...LOW-LEVEL MOISTURE /BOUNDARY LAYER DEWPOINTS OF 56-62

F/ CONTINUES TO SURGE NWD/NNWWD INTO WRN KS FROM OK...TO THE E OF A

CONFLUENCE BOUNDARY FROM W OF LBL TO NEAR GLD. THE DEEPER MIXED

LAYER AND MUCH DRIER BOUNDARY LAYER IS LOCATED TO THE W ACROSS ERN

CO. THE SURFACE MOISTURE GRADIENT MAY TEND TO CONSOLIDATE THROUGH

THE EVENING ACROSS EXTREME WRN KS...PROVIDING A FOCUS FOR STORM

INITIATION. THE MOISTENING BOUNDARY LAYER AND TEMPERATURES IN THE

LOW-MID 70S WILL SUPPORT STRONG INSTABILITY /MLCAPE VALUES IN EXCESS

OF 2000 J/KG/. AT THE SAME TIME...VERTICAL SHEAR WILL BECOME

INCREASINGLY FAVORABLE FOR SUPERCELLS INTO THIS EVENING. GIVEN THAT

THE INITIAL DEVELOPMENT SHOULD BE DISCRETE SUPERCELLS ACROSS WRN

KS...WITH THE POTENTIAL FOR VERY LARGE HAIL AND A COUPLE OF STRONG

TORNADOES. LATER THIS EVENING INTO TONIGHT...STORMS MAY GRADUALLY

MERGE INTO A LARGER N-S CONVECTIVE BAND WITH MORE OF A DAMAGING WIND

AND LARGE HAIL THREAT.

AVIATION...TORNADOES AND A FEW SEVERE THUNDERSTORMS WITH HAIL

SURFACE AND ALOFT TO 3 INCHES. EXTREME TURBULENCE AND SURFACE

WIND GUSTS TO 60 KNOTS. A FEW CUMULONIMBI WITH MAXIMUM TOPS TO

500. MEAN STORM MOTION VECTOR 21040.

...THOMPSON

SEL3