Big Severe Wx Outbreak around 10/18/07 in Plains

[CrazyC83]

Cells trying to develop in western Oklahoma on the dryline now.

[dtrain44]

I don't think anything is over west of and along I-35 - we've got a cumulus buildup along the dry line and possible convective initiation as far west as Altus. From Norman ST forecast:

...REGIONAL WEATHER DISCUSSION...
AT 145 PM...A LINE OF STRONG THUNDERSTORMS EXTENDED FROM
STILLWATER...TO SHAWNEE...AND PAULS VALLEY. THESE STORMS HAVE
DEVELOPED IN A FAVORABLE ENVIRONMENT FOR ORGANIZED SEVERE
STORMS...INCLUDING CAPE VALUES BETWEEN 800 AND 1200...ALONG WITH
STRONG VERTICAL WIND SHEAR. THESE STORMS ARE EXPECTED TO MOVE VERY
QUICKLY EASTWARD THIS AFTERNOON...AND SHOULD INCREASE IN BOTH NUMBER
AND INTENSITY AS A STRONG UPPER LEVEL TROUGH AFFECTS THE AREA.

MEANWHILE...A STRENGTHENING DRYLINE EXTENDED FROM NEAR WOODWARD...TO
ELK CITY...MANGUM...FREDERICK...AND ARCHER CITY TEXAS. VISIBLE
SATELLITE IMAGERY SHOWED CUMULUS CLOUDS EXPANDING NEAR AND AHEAD OF
THE DRYLINE...WITH RADAR IMAGERY SHOWING A HIGH BASED SHOWER
DEVELOPING NORTH OF CHEYENNE. WITH SUBSIDENCE BEGINNING TO
OVERSPREAD WESTERN OKLAHOMA...IT IS UNCLEAR THAT THUNDERSTORMS WILL
EVENTUALLY DEVELOP IN THIS CUMULUS CLOUD FIELD. HOWEVER...IF STORMS
DEVELOP...CAPE VALUES BETWEEN 1000 AND 1800 ALONG WITH STRONG
VERTICAL SHEAR SUPPORT THE POSSIBILITY OF SEVERE STORMS...INCLUDING
SUPERCELLS.

$$
JAMES

The threat is obviously much more conditional west of I-35 than in areas to the east, but I don't think the western third of Oklahoma can rest easy until later this evening.

[CrazyC83]

SPECIAL WEATHER STATEMENT
NATIONAL WEATHER SERVICE NORMAN OK
201 PM CDT WED OCT 17 2007

OKZ010-015-171930-
DEWEY OK-WOODWARD OK-
201 PM CDT WED OCT 17 2007

...SIGNIFICANT WEATHER ADVISORY...

THIS SIGNIFICANT WEATHER ADVISORY IS FOR DEWEY AND WOODWARD COUNTIES.

A STRONG THUNDERSTORM WAS LOCATED 5 MILES NORTHEAST OF LEEDEY AT 201
PM CDT...MOVING NORTHEAST AT 50 MPH. SMALL HAIL AND WINDS AROUND 50
MPH ARE POSSIBLE. THIS STORM HAS BEEN SLOWLY INCREASING IN INTENSITY
AND IF THIS TREND CONTINUES...A SEVERE THUNDERSTORM WARNING MAY BE
REQUIRED.

$$

For the W OK cell

[Ed Mahmoud]

In Texas, dry line is through Abilene and Graham, seems to be right at Jacksboro and Wichita Falls. Winds just shifting there now, dewpoint just starting to drop. Broken line of unimpressive cu on dry line.

[CrazyC83]

Now a warning on the W OK cell.

[CrazyC83]

Current conditions in the threat area - 2:00 pm CDT:

Arkansas
Batesville - Partly cloudy, 72 (70)
El Dorado - Light rainshower, 73 (72)
Fayetteville - Mostly cloudy, 74 (66)
Fort Smith - Partly cloudy, 80 (69)
Hot Springs - Mostly cloudy, 73 (70)
Jonesboro - Light rainshower, 74 (67)
Little Rock - Overcast, 72 (70)
Mena - Overcast, 75 (72)
Monticello - Light rainshower, 78 (71)
Mountain Home - Mostly cloudy, 70 (67)
Pine Bluff - Light rain, 75 (72)
Searcy - Light rain, 71 (69)
Texarkana - Mostly cloudy, 79 (71)

Kansas
Chanute - Light rain, 61 (58)
Coffeyville - Overcast, 63 (59)
Emporia - Heavy rain, 61 (59)
Hutchison - Overcast, 63 (57)
Parsons - Light rain, 62 (60)
Salina - Mostly cloudy, 63 (57)
Topeka - Rain, 62 (61)
Wichita - Thunderstorm, 61 (58)

Louisiana
Alexandria - Mostly cloudy, 81 (73)
Lafayette - Partly cloudy, 84 (73)
Lake Charles - Light rainshower, 75 (69)
Monroe - Partly cloudy, 82 (71)
Shreveport - Thunderstorm, 70 (66)

Mississippi
Greenville - Mostly cloudy, 79 (71)
Natchez - Mostly cloudy, 82 (72)

Missouri
Cape Girardeau - Mostly cloudy, 78 (66)
Columbia - Overcast, 68 (63)
Joplin - A few clouds, 80 (65)
Kansas City - Thunderstorm, 61 (59)
Poplar Bluff - Mostly cloudy, 75 (66)
Rolla - Mostly cloudy, 71 (65)
St. Louis - Overcast, 67 (63)
Springfield - Partly cloudy, 72 (65)
West Plains - Partly cloudy, 68 (66)

Oklahoma
Ada - Thunder, 79 (66)
Altus - Sunny, 82 (46)
Bartlesville - Overcast, 64 (60)
Enid - Thunderstorm, 61 (59)
Lawton - A few clouds, 84 (63)
McAlester - A few clouds, 79 (68)
Muskogee - A few clouds, 81 (66)
Norman - Mostly cloudy, 72 (70)
Oklahoma City - Partly cloudy, 75 (67)
Stillwater - Thunderstorm, 70 (67)
Tulsa - Partly cloudy, 79 (66)
Woodward - Sunny, 81 (46)

Tennessee
Dyersburg - Mostly cloudy, 79 (64)
Jackson - Partly cloudy, 81 (66)
Memphis - Light rainshower, 76 (68)

Texas
Beaumont - Light rain, 80 (75)
DFW - A few clouds, 86 (67)
Greenville - A few clouds, 82 (72)
Jasper - Overcast, 80 (77)
Lufkin - Light rain, 77 (73)
Mount Pleasant - Overcast, 73 (70)
Paris - Mostly cloudy, 79 (73)
Sherman - A few clouds, 81 (64)
Tyler - A few clouds, 84 (71)
Wichita Falls - Mostly cloudy, 78 (64)

[CrazyC83]

TORNADO WARNING
LAC015-119-172000-
/O.NEW.KSHV.TO.W.0022.071017T1910Z-071017T2000Z/

BULLETIN - EAS ACTIVATION REQUESTED
TORNADO WARNING
NATIONAL WEATHER SERVICE SHREVEPORT LA
210 PM CDT WED OCT 17 2007

THE NATIONAL WEATHER SERVICE IN SHREVEPORT HAS ISSUED A

* TORNADO WARNING FOR...
BOSSIER PARISH IN NORTHWEST LOUISIANA...
THIS INCLUDES THE CITY OF RED CHUTE...
WEBSTER PARISH IN NORTHWEST LOUISIANA...

* UNTIL 300 PM CDT

* AT 204 PM CDT...NATIONAL WEATHER SERVICE DOPPLER RADAR INDICATED A
SEVERE THUNDERSTORM CAPABLE OF PRODUCING A TORNADO NEAR RED
CHUTE...MOVING NORTHEAST AT 30 MPH.

* THE TORNADO WILL BE NEAR...
COTTON VALLEY BY 240 PM CDT...
SAREPTA BY 245 PM CDT...
9 MILES SOUTHEAST OF CULLEN BY 250 PM CDT...

DO NOT USE YOUR CAR TO TRY TO OUTRUN A TORNADO. CARS ARE EASILY
TOSSED AROUND BY TORNADO WINDS. IF YOU ARE CAUGHT IN THE PATH OF A
TORNADO...LEAVE THE CAR AND GO TO A STRONG BUILDING. IF NO SAFE
STRUCTURE IS NEARBY...SEEK SHELTER IN A DITCH OR LOW SPOT AND COVER
YOUR HEAD.

HEAVY RAINFALL MAY OBSCURE THIS TORNADO. TAKE COVER NOW! IF YOU WAIT
TO SEE OR HEAR IT COMING...IT MAY BE TOO LATE TO GET TO A SAFE PLACE.

LAT...LON 3300 9346 3277 9326 3251 9362 3265 9375
TIME...MOT...LOC 1910Z 224DEG 28KT 3264 9361

$$

VII

[CrazyC83]

SEVERE THUNDERSTORM WARNING
OKC039-043-172000-
/O.NEW.KOUN.SV.W.0626.071017T1911Z-071017T2000Z/

BULLETIN - IMMEDIATE BROADCAST REQUESTED
SEVERE THUNDERSTORM WARNING
NATIONAL WEATHER SERVICE NORMAN OK
211 PM CDT WED OCT 17 2007

THE NATIONAL WEATHER SERVICE IN NORMAN HAS ISSUED A

* SEVERE THUNDERSTORM WARNING FOR...
DEWEY COUNTY IN NORTHWEST OKLAHOMA...
NORTHWESTERN CUSTER COUNTY IN WESTERN OKLAHOMA...

* UNTIL 300 PM CDT

* AT 211 PM CDT...NATIONAL WEATHER SERVICE DOPPLER RADAR INDICATED A
SEVERE THUNDERSTORM 5 MILES NORTHEAST OF LEEDEY...MOVING NORTHEAST
AT 50 MPH. HAIL UP TO THE SIZE OF QUARTERS AND WINDS OF 60 MPH ARE
LIKELY. ANOTHER INTENSIFYING THUNDERSTORM WAS LOCATED NEAR MOOREWOOD
AND WAS ALSO MOVING NORTHEAST AT 50 MPH.

* LOCATIONS IN THE WARNING INCLUDE CAMARGO...CESTOS...LEEDEY...
MOOREWOOD...SEILING AND TALOGA.

SEVERE THUNDERSTORMS CAN PRODUCE TORNADOES WITH NO ADVANCE WARNING.
MOVE IMMEDIATELY TO A STORM SHELTER... BASEMENT OR STURDY BUILDING IF
A TORNADO IS SIGHTED.

LAT...LON 3617 9924 3616 9870 3562 9938 3598 9938
TIME...MOT...LOC 1911Z 228DEG 32KT 3594 9924

$$

[CrazyC83]

SEL1

URGENT - IMMEDIATE BROADCAST REQUESTED
TORNADO WATCH NUMBER 711
NWS STORM PREDICTION CENTER NORMAN OK
225 PM CDT WED OCT 17 2007

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

PARTS OF SOUTH CENTRAL KANSAS
MUCH OF OKLAHOMA

EFFECTIVE THIS WEDNESDAY AFTERNOON AND EVENING FROM 225 PM UNTIL
1000 PM CDT.

TORNADOES...HAIL TO 2 INCHES IN DIAMETER...THUNDERSTORM WIND
GUSTS TO 80 MPH...AND DANGEROUS LIGHTNING ARE POSSIBLE IN THESE
AREAS.

THE TORNADO WATCH AREA IS APPROXIMATELY ALONG AND 110 STATUTE
MILES EAST AND WEST OF A LINE FROM 60 MILES EAST NORTHEAST OF
MEDICINE LODGE KANSAS TO 15 MILES SOUTHWEST OF DURANT OKLAHOMA.
FOR A COMPLETE DEPICTION OF THE WATCH SEE THE ASSOCIATED WATCH
OUTLINE UPDATE (WOUS64 KWNS WOU1).

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...THIS TORNADO WATCH REPLACES TORNADO
WATCH NUMBER 708. WATCH NUMBER 708 WILL NOT BE IN EFFECT AFTER
225 PM CDT. CONTINUE...WW 709...WW 710...

DISCUSSION...SEVERE THUNDERSTORMS EXPECTED TO REDEVELOP ALONG AND E
OF DRY LINE WRN OK. WITH STRONG SHEAR PROFILES IN PLACE AND AIR MASS
REMAINING MDTLY UNSTABLE...SUPERCELLS INCLUDING TORNADOES ARE
EXPECTED TO DEVELOP AND SPREAD EWD AHEAD OF VIGOROUS UPPER TROUGH.

AVIATION...TORNADOES AND A FEW SEVERE THUNDERSTORMS WITH HAIL
SURFACE AND ALOFT TO 2 INCHES. EXTREME TURBULENCE AND SURFACE
WIND GUSTS TO 70 KNOTS. A FEW CUMULONIMBI WITH MAXIMUM TOPS TO
550. MEAN STORM MOTION VECTOR 23045.


...HALES

[CrazyC83]

MESOSCALE DISCUSSION 2095
NWS STORM PREDICTION CENTER NORMAN OK
0236 PM CDT WED OCT 17 2007

AREAS AFFECTED...ERN TX...LA...SRN AR

CONCERNING...TORNADO WATCH 710...

VALID 171936Z - 172130Z

THE SEVERE WEATHER THREAT FOR TORNADO WATCH 710 CONTINUES.

THE THREAT FOR TORNADOES CONTINUES WITHIN WW 710.

LOW LEVEL WARM/MOIST ADVECTION CONTINUES WITH GPS WATER VAPOR
SENSORS CURRENTLY INDICATING 2.00-2.32 INCHES FROM LA INTO SRN AR.
MEANWHILE...SATELLITE IMAGERY INDICATES LOW LEVEL VORTICITY CENTER
MOVING NWD ALONG THE SABINE RIVER...ON CYCLONIC SIDE OF 700 MB
JETLET OVER THE LOWER MS VALLEY. THIS FEATURE IS HELPING TO FOCUS
CONVECTION AND WILL CONTINUE NWD INTO AR.

SHEAR PROFILES ARE ALREADY FAVORABLE FOR ROTATING UPDRAFTS AND
TORNADOES...ALTHOUGH RELATIVELY WARM PROFILES AND WEAK LAPSE RATES
HAVE ACTED TO SLOW DEVELOPMENT. SHEAR PROFILES WILL LIKELY INCREASE
WITH TIME AS UPPER TROUGH CONTINUES TO DEVELOP NEWD. THIS WILL
MAINTAIN OR INCREASE TORNADO THREAT FARTHER N INTO AR...AND POSSIBLY
SERN MO...WHERE AN ADDITIONAL WW MAY BE REQUIRED LATER TODAY INTO
THIS EVENING.

..JEWELL.. 10/17/2007


ATTN...WFO...JAN...LIX...LZK...LCH...SHV...HGX...FWD...

29399151 29439206 29669325 29659404 29579439 31299483
31789541 32949564 33789548 34349417 34289205 33649137
31719143

[Ed Mahmoud]

Just looking closely at the dewpoints shown on the newest SPC MCD, and the dry line isn't a line at all. It is a squiggle.

[CrazyC83]

DAY 1 CONVECTIVE OUTLOOK
NWS STORM PREDICTION CENTER NORMAN OK
0236 PM CDT WED OCT 17 2007

VALID 172000Z - 181200Z

...THERE IS A MDT RISK OF SVR TSTMS FROM THE ARKLATEX REGION INTO
CENTRAL MO...

...THERE IS A SLGT RISK OF SVR TSTMS FROM SRN LA INTO SRN IA...

...ARKLATEX NWD INTO THE MID MS VALLEY...

COMPLEX SYNOPTIC PATTERN IS EVOLVING ACROSS THE MIDDLE PORTION OF
THE COUNTRY THIS AFTERNOON. OF PARTICULAR NOTE...LATEST DIAGNOSTIC
DATA SUGGESTS SFC LOW IS BEGINNING TO DEEPEN OVER NWRN KS WITH A
TRAILING DRYLINE INTO WRN OK. LATEST WV IMAGERY INDICATES SUBTLE
BUT SIGNIFICANT MID LEVEL MOISTENING/ASCENT IN ASSOCIATION WITH
UPPER VORT ACROSS SWRN OK INTO NWRN TX. THIS FEATURE APPEARS MOSTLY
RESPONSIBLE...ALONG WITH STRONG BOUNDARY LAYER HEATING...FOR RECENT
THUNDERSTORM DEVELOPMENT ALONG DRYLINE OVER WCNTRL OK FROM DEWEY
INTO CUSTER COUNTIES. THIS CONVECTIVE MODE IS IN LINE WITH EARLIER
WRF-NMM4 FORECAST OF DISCRETE SUPERCELLS IN WAKE OF EARLY MORNING
ACTIVITY. 19Z SOUNDING FROM OUN STRONGLY SUPPORTS FAST-MOVING
SUPERCELLS WITH STORM MOTIONS IN EXCESS OF 50KT. IN ADDITION TO
DAMAGING WINDS ANY DISCRETE STRUCTURES COULD ALSO PRODUCE TORNADOES.
GIVEN THIS SCENARIO...IT APPEARS THIS ACTIVITY SHOULD CONTINUE TO
STRENGTHEN WITHIN STRONGLY SHEARED ENVIRONMENT. WITH TIME THIS
ACTIVITY SHOULD SPREAD DOWNSTREAM ALONG A FAIRLY WELL DEFINED LOW
LEVEL BAROCLINIC ZONE FROM NCNTRL OK INTO SERN KS/WCNTRL MO.
STRATUS HAS YET TO ERODE NORTH OF THIS OUTFLOW AND SHOULD SERVE AS A
FOCUS FOR ROBUST SEVERE STORMS INTO THE OVERNIGHT HOURS.

FARTHER SOUTH...REMNANTS OF WRN GULF TROPICAL FEATURE HAVE LIFTED
NWD ALONG THE SABINE RIVER OVER ERN TX/WRN LA. LEADING EDGE OF THIS
TROPICAL SURGE IS NOW INTO SRN AR. WITH TIME THIS DEEP MOIST PLUME
WILL SPREAD INTO MO AHEAD OF STRONG SPEED MAX/SHORTWAVE TROUGH.
NUMEROUS SUPERCELL-LIKE STRUCTURES WILL BE NOTED BENEATH THIS NWD
MOVING TROPICAL SURGE...ALONG WITH ISOLATED TORNADOES. AS THIS
AIRMASS INTERACTS WITH STRONGER SHEAR FARTHER NORTH...ENVIRONMENTAL
CONDITIONS SHOULD BECOME SOMEWHAT MORE FAVORABLE FOR STRONGER
UPDRAFTS POTENTIALLY A FEW STRONG TORNADOES.

..DARROW.. 10/17/2007

CLICK TO GET WUUS01 PTSDY1 PRODUCT

NOTE: THE NEXT DAY 1 OUTLOOK IS SCHEDULED BY 0100Z
CURRENT UTC TIME: 1952Z (3:52PM), RELOAD THIS PAGE TO UPDATE THE TIME

[CrazyC83]

ORNADO WARNING
ARC027-LAC027-119-172030-
/O.NEW.KSHV.TO.W.0023.071017T1952Z-071017T2030Z/

BULLETIN - EAS ACTIVATION REQUESTED
TORNADO WARNING
NATIONAL WEATHER SERVICE SHREVEPORT LA
252 PM CDT WED OCT 17 2007

THE NATIONAL WEATHER SERVICE IN SHREVEPORT HAS ISSUED A

* TORNADO WARNING FOR...
CLAIBORNE PARISH IN NORTHWEST LOUISIANA...
WEBSTER PARISH IN NORTHWEST LOUISIANA...
COLUMBIA COUNTY IN SOUTHWEST ARKANSAS...

* UNTIL 330 PM CDT

* AT 251 PM CDT...NATIONAL WEATHER SERVICE DOPPLER RADAR INDICATED A
SEVERE THUNDERSTORM CAPABLE OF PRODUCING A TORNADO 7 MILES
SOUTHWEST OF EMERSON...OR ABOUT 10 MILES EAST OF SPRINGHILL...
MOVING NORTHEAST AT 50 MPH.

* THE TORNADO WILL BE NEAR...
EMERSON BY 300 PM CDT...

IF YOU ARE CAUGHT OUTSIDE...SEEK SHELTER IN A NEARBY REINFORCED
BUILDING. AS A LAST RESORT...SEEK SHELTER IN A CULVERT...DITCH OR LOW
SPOT AND COVER YOUR HEAD WITH YOUR HANDS.

IF IN MOBILE HOMES OR VEHICLES...EVACUATE THEM AND GET INSIDE A
STURDY SHELTER. IF NO SHELTER IS AVAILABLE...LIE FLAT IN THE NEAREST
DITCH OR OTHER LOW SPOT AND COVER YOUR HEAD WITH YOUR HANDS.

LAT...LON 3337 9310 3312 9298 3292 9325 3305 9340
TIME...MOT...LOC 1952Z 227DEG 46KT 3304 9328

$$

VII

[RL3AO]

Down to 990mb over SW Kansas.

[CrazyC83]

New watch for central Kansas/south-central Nebraska (a severe thunderstorm watch)

[CrazyC83]

SEL2

URGENT - IMMEDIATE BROADCAST REQUESTED
SEVERE THUNDERSTORM WATCH NUMBER 712
NWS STORM PREDICTION CENTER NORMAN OK
300 PM CDT WED OCT 17 2007

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

CENTRAL KANSAS
PARTS OF SOUTHERN NEBRASKA

EFFECTIVE THIS WEDNESDAY AFTERNOON AND EVENING FROM 300 PM UNTIL
1000 PM 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 65
STATUTE MILES EAST AND WEST OF A LINE FROM 20 MILES NORTH OF
KEARNEY NEBRASKA TO 45 MILES SOUTHWEST OF HUTCHINSON KANSAS. FOR
A COMPLETE DEPICTION OF THE WATCH SEE THE ASSOCIATED WATCH
OUTLINE UPDATE (WOUS64 KWNS WOU2).

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.

OTHER WATCH INFORMATION...CONTINUE...WW 709...WW 710...WW 711...

DISCUSSION...THUNDERSTORMS DEVELOPING VICINITY OF DEEPENING SURFACE
LOW NRN KS AND EVENTUALLY SWD ALONG DRY LN INTO NWRN OK. WITH STEEP
MID LEVEL LAPSE RATES AND 30-40KT OF SHEAR...A FEW SUPERCELLS ARE
LIKELY. PRIMARY THREAT WILL BE LARGE HAIL AND LOCALLY DAMAGING
WINDS.

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 450. MEAN STORM
MOTION VECTOR 23025.


...HALES

[RL3AO]

Thunderstorms developing in Western Oklahoma.

[CrazyC83]

Thunderstorms developing in Western Oklahoma.

Gone from blank radar screens to a bunch of severe storms in barely 30 minutes...

[CrazyC83]

Live coverage: http://www.koco.com/video/10731634/index.html

[HarlequinBoy]

Is Shreveport streaming?