Major derecho - May 8 - Plains to Ohio Valley (beyond?)

[Dave]

BULLETIN - EAS ACTIVATION REQUESTED
SEVERE THUNDERSTORM WARNING
NATIONAL WEATHER SERVICE PADUCAH KY
1134 AM CDT FRI MAY 8 2009

THE NATIONAL WEATHER SERVICE IN PADUCAH HAS ISSUED A

* SEVERE THUNDERSTORM WARNING FOR...
JOHNSON COUNTY IN SOUTHERN ILLINOIS...
MASSAC COUNTY IN SOUTHERN ILLINOIS...
POPE COUNTY IN SOUTHERN ILLINOIS...
EASTERN PULASKI COUNTY IN SOUTHERN ILLINOIS...
EASTERN BALLARD COUNTY IN WESTERN KENTUCKY...
SOUTHWESTERN LIVINGSTON COUNTY IN WESTERN KENTUCKY...
MCCRACKEN COUNTY IN WESTERN KENTUCKY...

* UNTIL 1230 PM CDT.

* AT 1133 AM CDT...NATIONAL WEATHER SERVICE DOPPLER RADAR INDICATED A
LINE OF SEVERE THUNDERSTORMS CAPABLE OF PRODUCING QUARTER SIZE
HAIL...AND DESTRUCTIVE WINDS IN EXCESS OF 70 MPH. THESE STORMS
WERE LOCATED ALONG A LINE EXTENDING FROM 14 MILES WEST OF GOREVILLE
TO 7 MILES SOUTH OF BARLOW...MOVING NORTHEAST AT 45 MPH.

* LOCATIONS IN THE WARNED AREA INCLUDE...
LA CENTER...
LOVELACEVILLE...
KARNAK...
GOREVILLE...
WEST PADUCAH...
LAKE OF EGYPT AREA...
VIENNA...
LONE OAK...
NEW COLUMBIA...
METROPOLIS...

[Dave]

BULLETIN - EAS ACTIVATION REQUESTED
TORNADO WARNING
NATIONAL WEATHER SERVICE PADUCAH KY
1139 AM CDT FRI MAY 8 2009

THE NATIONAL WEATHER SERVICE IN PADUCAH HAS ISSUED A

* TORNADO WARNING FOR...
PERRY COUNTY IN SOUTH CENTRAL ILLINOIS...

* UNTIL 1215 PM CDT.

* AT 1137 AM CDT...TRAINED WEATHER SPOTTERS REPORTED A FUNNEL CLOUD 8
MILES SOUTH SOUTHWEST OF PINCKNEYVILLE...MOVING EAST AT 30 MPH.
AMATEUR RADIO OPERATORS RELAYED AN UNCONFIRMED REPORT OF A BRIEF
TORNADO TOUCHDOWN IN THIS AREA.

* LOCATIONS IN THE WARNED AREA INCLUDE...
PINCKNEYVILLE...
DU QUOIN...
TAMAROA...

PRECAUTIONARY/PREPAREDNESS ACTIONS...

IN ADDITION TO THE TORNADO...THIS STORM IS CAPABLE OF PRODUCING UP
TO QUARTER SIZE HAIL AND DESTRUCTIVE STRAIGHT LINE WINDS.

[Dave]

Have to leave for awhile.

[srainhoutx]

BULLETIN - EAS ACTIVATION REQUESTED
TORNADO WARNING
NATIONAL WEATHER SERVICE ST LOUIS MO
1145 AM CDT FRI MAY 8 2009

THE NATIONAL WEATHER SERVICE IN ST LOUIS HAS ISSUED A

* TORNADO WARNING FOR...
STE. GENEVIEVE COUNTY IN SOUTHEAST MISSOURI...
NORTHEAST ST. FRANCOIS COUNTY IN SOUTHEAST MISSOURI...

* UNTIL 1230 PM CDT

* AT 1137 AM CDT...TRAINED WEATHER SPOTTERS REPORTED A TORNADO 2
MILES WEST OF FARMINGTON. DOPPLER RADAR SHOWED THIS TORNADO MOVING
EAST AT 30 MPH.

* LOCATIONS IMPACTED INCLUDE...
ROCKY RIDGE...WOMAC...WEINGARTEN...COFFMAN...BLOOMSDALE...ST.
MARY...FRENCH VILLAGE...RIVER AUX VASES AND MINNITH.

[srainhoutx]

TORNADO WARNING
ILC055-077-199-081730-
/O.NEW.KPAH.TO.W.0040.090508T1651Z-090508T1730Z/

BULLETIN - EAS ACTIVATION REQUESTED
TORNADO WARNING
NATIONAL WEATHER SERVICE PADUCAH KY
1151 AM CDT FRI MAY 8 2009

THE NATIONAL WEATHER SERVICE IN PADUCAH HAS ISSUED A

* TORNADO WARNING FOR...
SOUTHERN FRANKLIN COUNTY IN SOUTH CENTRAL ILLINOIS...
EASTERN JACKSON COUNTY IN SOUTHERN ILLINOIS...
NORTHERN WILLIAMSON COUNTY IN SOUTHERN ILLINOIS...

* UNTIL 1230 PM CDT.

* AT 1140 AM CDT...THE PUBLIC REPORTED A TORNADO 3 MILES WEST OF
MURPHYSBORO. AT 1150 AM...RADAR INDICATED THE ROTATION WAS NEAR
DESOTO...MOVING NORTHEAST AT 45 MPH.

* LOCATIONS IN THE WARNED AREA INCLUDE...
HURST...
CAMBRIA...
CARTERVILLE...
ZEIGLER...
ROYALTON...
HERRIN...
ENERGY...
JOHNSTON CITY...
WEST FRANKFORT...
THOMPSONVILLE...

[srainhoutx]

SEVERE WEATHER STATEMENT
NATIONAL WEATHER SERVICE ST LOUIS MO
1152 AM CDT FRI MAY 8 2009

MOC186-187-081730-
/O.CON.KLSX.TO.W.0015.000000T0000Z-090508T1730Z/
ST. FRANCOIS MO-STE. GENEVIEVE MO-
1152 AM CDT FRI MAY 8 2009

...A TORNADO WARNING REMAINS IN EFFECT UNTIL 1230 PM CDT FOR STE.
GENEVIEVE AND NORTHEASTERN ST. FRANCOIS COUNTIES...

AT 1151 AM CDT...NATIONAL WEATHER SERVICE DOPPLER RADAR CONTINUED TO
INDICATE A TORNADO. THIS TORNADO WAS LOCATED NEAR DESLOGE...MOVING
EAST AT 15 MPH.

LOCATIONS IMPACTED INCLUDE...
ROCKY RIDGE...WEINGARTEN...COFFMAN...BLOOMSDALE...WOMAC...ST.
MARY...FRENCH VILLAGE...RIVER AUX VASES AND MINNITH.

[srainhoutx]

Moderate Risk continues...



DAY 1 CONVECTIVE OUTLOOK
NWS STORM PREDICTION CENTER NORMAN OK
1142 AM CDT FRI MAY 08 2009

VALID 081630Z - 091200Z

...THERE IS A MDT RISK OF SVR TSTMS PORTIONS OF WRN KY AND NRN TN...

...THERE IS A SLGT RISK OF SVR TSTMS FROM THE SRN PLAINS EWD THROUGH
THE TN/LOWER OH VALLEYS EWD TO THE CAROLINAS...

...THERE IS A SLGT RISK OF SVR TSTMS IN THE IA AREA...

...TN/LOWER OH VALLEY...
LONG LIVED BOW ECHO...MOVING EWD AT 60 KT...WAS APPROACHING THE MS
RIVER AND IS EXPECTED TO TRACK MOSTLY EWD THROUGH THE REGION THIS
AFTERNOON. THOUGH MESOSCALE MODELS SUGGEST WEAKENING WITH
TIME...GIVEN THE WELL ORGANIZED SYSTEM MOVING INTO AN ENVIRONMENT
WITH STRONG INSTABILITY...MLCAPES 2000-2500 J/KG...AND EFFECTIVE
SHEAR NEAR 40 KT IS EXPECTED TO SUSTAIN WIDESPREAD WIND
DAMAGE..SOMETIMES EXTREME. WIND AND HAIL IS FORECAST WITH THE SYSTEM
UNTIL IT REACHES THE APPALACHIANS THIS EVENING. LOW LEVEL SHEAR WILL
ALSO BE SUPPORTIVE OF TORNADOES...ESPECIALLY WITH THE ROTATING BOW
HEADS.

...NRN TX/SERN OK/AR/NRN LA...
COLD FRONT AT MID MORNING EXTENDED FROM SERN KS SWWD INTO WRN TX
NEAR LBB. FRONT IS EXPECTED TO MOVE SEWD TO NEAR A SGF-ADM-MAF LINE
BY 23Z. MORNING SOUNDINGS SHOWED STRONG CAPPING BETWEEN 850-700
MB...AND THIS SHOULD LIMIT CONVECTION ALONG THE FRONT THROUGH MOST
OF THE DAY. DESPITE NO REAL DISCERNABLE SHORTWAVE TROUGH...MODELS
DEPICT A SPEED MAX MOVING INTO THE REGION LATE THIS AFTERNOON WITH
INCREASING DIFFLUENCE ALOFT. THIS WOULD RESULT IN STRENGTHENING LOW
LEVEL CONVERGENCE ALONG THE FRONT... ESPECIALLY IN AND WEST OF THE
ARKLATEX. ALL OPERATIONAL/MESOSCALE MODELS SHOW CONVECTION DEVELOPS
ALONG THE FRONT IN ERN OK/NRN TX AFTER 22Z. STORMS THAT DEVELOP ARE
LIKELY TO QUICKLY BECOME SEVERE GIVEN MLCAPES FROM 3000 TO 4000 J/KG
AND MID LEVEL LAPSE RATES NEAR 9 C/KM INDICATE VERY LARGE HAIL WOULD
BE THE MAIN THREAT.

...CAROLINAS.....
REMNANT MCS FROM WRN NC INTO NERN GA IS EXPECTED TO CONTINUE EWD KY
INTO OVER KY/TN WILL CROSS THE APPALACHIANS THIS MORNING
A MOIST AND DESTABILIZING AIR MASS...2000 J/KG MLCAPE AS WITH
TEMPERATURES IN THE 80S. ALTHOUGH ACTIVITY WILL GRADUALLY DEVELOP
SOUTH OF THE STRONGER WINDS ALOFT...UNIDIRECTIONAL WLY WINDS AT 20
TO 30 KT THROUGH THE LOWER 6 KM MAY SUPPORT A LINEAR SYSTEM THIS
AFTERNOON...WITH WIND DAMAGE THE PRIMARY THREAT.

...IA/NWRN IL AND SWRN WI...
A STRONG SHORTWAVE TROUGH OVER CENTRAL NEB/SD WILL TRACK EWD TO NEAR
THE NEB/IA BORDER BY 00Z. COLD TEMPERATURES ALOFT...500 MB
TEMPERATURES FROM -18 TO -22C...MODERATELY STEEP LAPSE RATES...40-50
KT DEEP LAYER SHEAR AND LIFT ASSOCIATED WITH TROUGH/ASSOCIATED JET
MAX SHOULD RESULT IN SUPERCELLS. HAIL AND WIND DAMAGE WILL BE THE
MAIN THREATS.

..IMY/GRAMS.. 05/08/2009

[srainhoutx]

More sad news...

1050 AM TSTM WND DMG 1 S POPLAR BLUFF 36.75N 90.41W
05/08/2009 BUTLER MO LAW ENFORCEMENT

*** 2 FATAL *** MISSOURI HIGHWAY PATROL REPORTED A TREE
FELL ON A CAR...THE CAR CAUGHT ON FIRE AND 2 PEOPLE
INSIDE WERE KILLED. LOCATION WAS ONE MILE SOUTH OF POPLAR
BLUFF ON HIGHWAY 53. TIME APPROXIMATE.

[CrazyC83]

What is stronger, a Tornado Watch primarily mentioning 105 mph winds, or a PDS Severe Thunderstorm Watch while showing a moderate tornado threat?

[srainhoutx]

SEVERE WEATHER STATEMENT
NATIONAL WEATHER SERVICE PADUCAH KY
1208 PM CDT FRI MAY 8 2009

ILC055-199-081730-
/O.CON.KPAH.TO.W.0040.000000T0000Z-090508T1730Z/
WILLIAMSON IL-FRANKLIN IL-
1208 PM CDT FRI MAY 8 2009

...A TORNADO WARNING REMAINS IN EFFECT UNTIL 1230 PM CDT FOR SOUTHERN
FRANKLIN COUNTY IN SOUTH CENTRAL ILLINOIS...AND NORTHERN WILLIAMSON
COUNTY IN SOUTHERN ILLINOIS...

AT 1206 PM CDT...THE ROTATING STORM WAS LOCATED NEAR FREEMAN
SPUR...MOVING NORTHEAST AT 45 MPH.

LOCATIONS IN THE WARNED AREA INCLUDE SPILLERTOWN...WHITEASH...
JOHNSTON CITY...ORIENT...PITTSBURG...WEST FRANKFORT...HANAFORD AND
THOMPSONVILLE.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

IN ADDITION TO THE TORNADO...THIS STORM IS CAPABLE OF PRODUCING LARGE
HAIL AND DESTRUCTIVE STRAIGHT LINE WINDS.

[srainhoutx]

What is stronger, a Tornado Watch primarily mentioning 105 mph winds, or a PDS Severe Thunderstorm Watch while showing a moderate tornado threat?

Tough call for SPC today. I did wonder why the hesitation on a PDS, but with some High Risk not materializing lately you have to wonder.

[CrazyC83]

What is stronger, a Tornado Watch primarily mentioning 105 mph winds, or a PDS Severe Thunderstorm Watch while showing a moderate tornado threat?

Tough call for SPC today. I did wonder why the hesitation on a PDS, but with some High Risk not materializing lately you have to wonder.

I would have gone with a PDS Tornado Watch there, even though the tornado probabilities are too low for such. The stronger the wording, the better. I'd also go up to a high risk with a 60H wind threat.

[CrazyC83]

MESOSCALE DISCUSSION 0761
NWS STORM PREDICTION CENTER NORMAN OK
1208 PM CDT FRI MAY 08 2009

AREAS AFFECTED...EXTREME IND...CNTRL AND ERN KY AND PORTIONS OF ERN
TN

CONCERNING...SEVERE POTENTIAL...WATCH LIKELY

VALID 081708Z - 081845Z

SEVERE THUNDERSTORM THREAT IS EXPECTED TO DEVELOP EWD THROUGH SRN
IND...CNTRL AND ERN KY THROUGH CNTRL AND ERN TN THE REMAINDER OF THE
AFTERNOON. A NEW WW WILL LIKELY BE NEEDED BEFORE 18Z.

BOW-ECHO COMMA-HEAD SYSTEM REMAINS WELL ORGANIZED AND EXTENDS FROM
SERN MO...SRN IL INTO EXTREME NERN AR. ACTIVITY IS MOVING EAST AT 50
TO 60 KT AND WILL APPROACH THE ERN EDGE OF TORNADO WATCH 267 BY
1830Z. PRE-CONVECTIVE WARM SECTOR IS MODERATELY UNSTABLE THROUGH W
CNTRL TN AND WRN KY...BUT INSTABILITY DECREASES SIGNIFICANTLY WITH
ERN EXTENT ACROSS ERN KY AND TN. A SWLY LOW LEVEL JET IS FORECAST TO
GRADUALLY STRENGTHEN NEWD INTO THE TN VALLEY AND SRN OH VALLEY THIS
AFTERNOON. THIS WILL CONTRIBUTE TO NEWD THETA-E ADVECTION AND
DESTABILIZATION WITH TIME. FURTHER DESTABILIZATION WILL OCCUR AS THE
BOUNDARY LAYER WARMS. STRENGTHENING LOW-MID LEVEL WIND FIELDS WILL
ALSO HELP TO SUSTAIN ORGANIZED STORM STRUCTURES WITHIN THE BROADER
MESOSCALE SYSTEM. OTHER STORMS ARE DEVELOPING ALONG WARM ADVECTION
WING AHEAD OF THE LINE ACROSS WRN KY. THERE SOME CONCERN THAT THIS
ACTIVITY COULD EVENTUALLY BECOME SURFACE BASED AS THE SURFACE LAYER
WARMS. ANY DISCRETE SURFACE BASED STORMS AHEAD OF THE LINE WOULD
LIKELY BECOME SUPERCELLULAR GIVEN FAVORABLE BULK SHEAR AND
INCREASING HODOGRAPH SIZE WITH TIME. DAMAGING WIND...ISOLATED
TORNADOES AND LARGE HAIL WILL BE POSSIBLE AS THE AFTERNOON
PROGRESSES.

..DIAL.. 05/08/2009


ATTN...WFO...MRX...JKL...ILN...LMK...OHX...HUN...

LAT...LON 35458450 35278641 36288638 38328660 38508434 37618296
35458450

[srainhoutx]

[srainhoutx]

Very Impressive...

[CrazyC83]

Looks like a hurricane over the Mississippi! Most impressive derecho I have seen in years - at this rate it could survive all the way to the Atlantic (and maybe reform into Tropical Storm Ana?)

[CrazyC83]

One thing I believe: the "Extreme Wind Warning" tropical product should be expanded to cover convective winds of 100 mph or more...they warrant much greater attention than a normal Severe Thunderstorm Warning (even if strongly worded)...

[srainhoutx]

SEVERE THUNDERSTORM WARNING
NATIONAL WEATHER SERVICE ST LOUIS MO
1227 PM Cdt FRI MAY 8 2009

THE NATIONAL WEATHER SERVICE IN ST LOUIS HAS ISSUED A

* SEVERE THUNDERSTORM WARNING FOR...
RANDOLPH COUNTY IN SOUTHWEST ILLINOIS...
STE. GENEVIEVE COUNTY IN SOUTHEAST MISSOURI...

* UNTIL 130 PM Cdt

* AT 1224 PM Cdt...NATIONAL WEATHER SERVICE DOPPLER RADAR INDICATED A
LINE OF SEVERE THUNDERSTORMS CAPABLE OF PRODUCING DESTRUCTIVE
HURRICANE FORCE WINDS WITH WIDESPREAD DAMAGE.. THESE STORMS WERE
LOCATED ALONG A LINE EXTENDING FROM ROCKY RIDGE TO WOMAC...AND
MOVING EAST AT 40 MPH.

[srainhoutx]

BULLETIN - EAS ACTIVATION REQUESTED
TORNADO WARNING
NATIONAL WEATHER SERVICE ST LOUIS MO
1231 PM Cdt FRI MAY 8 2009

THE NATIONAL WEATHER SERVICE IN ST LOUIS HAS ISSUED A

* TORNADO WARNING FOR...
NORTHEASTERN MADISON COUNTY IN SOUTHEAST MISSOURI...

* UNTIL 100 PM Cdt

* AT 1228 PM Cdt...TRAINED WEATHER SPOTTERS REPORTED A TORNADO
ON THE NORTH SIDE OF FREDERICKTOWN. DOPPLER RADAR SHOWED THIS
TORNADO MOVING EAST AT 40 MPH.

* LOCATIONS IMPACTED INCLUDE..
MAINLY RURAL AREAS OF NORTHEASTERN MADISON COUNTY.

[srainhoutx]

BULLETIN - EAS ACTIVATION REQUESTED
SEVERE THUNDERSTORM WARNING
NATIONAL WEATHER SERVICE PADUCAH KY
1233 PM CDT FRI MAY 8 2009

THE NATIONAL WEATHER SERVICE IN PADUCAH HAS ISSUED A

* SEVERE THUNDERSTORM WARNING FOR...
PERRY COUNTY IN SOUTH CENTRAL ILLINOIS...
JACKSON COUNTY IN SOUTHERN ILLINOIS...
NORTHERN UNION COUNTY IN SOUTHERN ILLINOIS...

* UNTIL 115 PM CDT.

* AT 1230 PM CDT...NATIONAL WEATHER SERVICE DOPPLER RADAR INDICATED A
SEVERE THUNDERSTORM CAPABLE OF PRODUCING DESTRUCTIVE WINDS IN
EXCESS OF 80 MPH. THIS STORM WAS LOCATED 24 MILES WEST OF GRAND
TOWER...MOVING EAST AT 60 MPH.

* LOCATIONS IN THE WARNED AREA INCLUDE...
GRAND TOWER...
AVA...
MURPHYSBORO...
DE SOTO...
CARBONDALE...
ELKVILLE...