Severe Storm threat- 5th-7th

[Dave]

1210 AM CDT TUE APR 6 2010

...A SEVERE THUNDERSTORM WARNING REMAINS IN EFFECT UNTIL 100 AM CDT
FOR EASTERN CARROLL COUNTY...

AT 1207 AM CDT...NATIONAL WEATHER SERVICE DOPPLER RADAR CONTINUED TO
INDICATE A SEVERE THUNDERSTORM CAPABLE OF PRODUCING DAMAGING WINDS IN
EXCESS OF 60 MPH. THIS STORM WAS LOCATED APPROXIMATELY NEAR HITT...
OR 14 MILES EAST OF MOUNT CARROLL...MOVING EAST AT 60 MPH.

[Dave]

BULLETIN - IMMEDIATE BROADCAST REQUESTED
SEVERE THUNDERSTORM WARNING
NATIONAL WEATHER SERVICE OMAHA/VALLEY NEBRASKA
1232 AM CDT TUE APR 6 2010

THE NATIONAL WEATHER SERVICE IN OMAHA HAS ISSUED A

* SEVERE THUNDERSTORM WARNING FOR...
SOUTHEASTERN BURT COUNTY IN EAST CENTRAL NEBRASKA...
EASTERN DODGE COUNTY IN EAST CENTRAL NEBRASKA...
WESTERN WASHINGTON COUNTY IN EAST CENTRAL NEBRASKA...

* UNTIL 100 AM CDT

* AT 1227 AM CDT...NATIONAL WEATHER SERVICE METEOROLOGISTS DETECTED A
SEVERE THUNDERSTORM CAPABLE OF PRODUCING QUARTER SIZE HAIL. THIS
STORM WAS LOCATED NEAR ARLINGTON...OR 24 MILES NORTHWEST OF
OMAHA...AND MOVING NORTHEAST AT 50 MPH.

* LOCATIONS IMPACTED INCLUDE...
CRAIG...TEKAMAH...HERMAN AND SUMMIT LAKE STATE RECREATION AREA.

[Dave]

BULLETIN - IMMEDIATE BROADCAST REQUESTED
SEVERE THUNDERSTORM WARNING
NATIONAL WEATHER SERVICE DES MOINES IA
1233 AM CDT TUE APR 6 2010

THE NATIONAL WEATHER SERVICE IN DES MOINES HAS ISSUED A

* SEVERE THUNDERSTORM WARNING FOR...
GUTHRIE COUNTY IN WEST CENTRAL IOWA...

* UNTIL 115 AM CDT

* AT 1230 AM CDT...NATIONAL WEATHER SERVICE DOPPLER RADAR INDICATED A
SEVERE THUNDERSTORM CAPABLE OF PRODUCING QUARTER SIZE HAIL. THIS
STORM WAS LOCATED 13 MILES SOUTHEAST OF AUDUBON...OR 60 MILES WEST
OF DES MOINES...AND MOVING EAST AT 45 MPH.

* LOCATIONS IMPACTED INCLUDE...
GUTHRIE CENTER...PANORA...CASEY...MENLO AND YALE.

[Dave]

BULLETIN - IMMEDIATE BROADCAST REQUESTED
SEVERE THUNDERSTORM WARNING
NATIONAL WEATHER SERVICE CHICAGO/ROMEOVILLE IL
1236 AM CDT TUE APR 6 2010

THE NATIONAL WEATHER SERVICE IN CHICAGO HAS ISSUED A

* SEVERE THUNDERSTORM WARNING FOR...
EASTERN BOONE COUNTY...
NORTHWESTERN COOK COUNTY...
DEKALB COUNTY...
KANE COUNTY...
WESTERN LAKE COUNTY...
LEE COUNTY...
MCHENRY COUNTY...

* UNTIL 130 AM CDT

* AT 1231 AM...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 CLINTON TO 7 MILES EAST OF
STILLMAN VALLEY TO 6 MILES NORTHEAST OF DEER GROVE...AND MOVING
EAST AT 55 MPH.

* LOCATIONS IMPACTED INCLUDE...
BELVIDERE...HARVARD...GENOA...MARENGO...SYCAMORE...DE KALB...
WOODSTOCK...WONDER LAKE...SHABBONA...MCHENRY...ALGONQUIN...PISTAKEE
HIGHLANDS...SLEEPY HOLLOW...FOX LAKE...CARPENTERSVILLE...ISLAND
LAKE...EAST DUNDEE...LONG LAKE...ELGIN AND WAUCONDA.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

THESE STORMS HAVE A HISTORY OF PRODUCING DESTRUCTIVE WINDS AND LARGE
HAIL. SEEK SHELTER NOW INSIDE A STURDY STRUCTURE AND STAY AWAY FROM
WINDOWS!

[Bunkertor]

NOTE: THE NEXT DAY 1 OUTLOOK IS SCHEDULED BY 0600Z
CURRENT UTC TIME: 0625Z (8:25AM), RELOAD THIS PAGE TO UPDATE THE TIME

Uhm ? 25 minutes delayed ?

[Bunkertor]

MESOSCALE DISCUSSION 0263
NWS STORM PREDICTION CENTER NORMAN OK
0120 AM CDT TUE APR 06 2010

AREAS AFFECTED...ERN NEB...IA

CONCERNING...SEVERE THUNDERSTORM WATCH 52...

VALID 060620Z - 060745Z

THE SEVERE WEATHER THREAT FOR SEVERE THUNDERSTORM WATCH 52
CONTINUES.

A LARGE HAIL THREAT WILL LIKELY CONTINUE ACROSS FAR ERN NEB AND
CNTRL IA AS STORMS MOVE NNEWD OVER THE NEXT FEW HOURS. THE SEVERE
THREAT WILL LIKELY DEVELOP A LITTLE NORTH OF THE WATCH AREA AND A
LOCAL EXTENSION OF THE WATCH ONE OR TWO TIERS OF COUNTIES TO THE
NORTH MAY BE APPROPRIATE.

A CLUSTER OF STRONG THUNDERSTORMS IS LOCATED FROM NEAR OMAHA EWD TO
WEST OF DES MOINES ON THE NORTH SIDE OF A STATIONARY FRONTAL
BOUNDARY. THE ACTIVITY IS LOCATED ALONG THE NRN EDGE OF A LOW-LEVEL
JET WHICH IS FORECAST TO DEVELOP AND STRENGTHEN NWD PROVIDING
SUPPORT FOR CONTINUED STORM INITIATION AND DEVELOPMENT. OBJECTIVE
ANALYSIS SHOWS A POCKET OF MODERATE INSTABILITY WITH MUCAPE VALUES
FROM 1500 TO 2500 J/KG ACROSS SE NEB. THE STORMS ARE FEEDING OFF OF
THIS INSTABILITY IN A STEEP LAPSE RATE ENVIRONMENT SUGGESTING THE
LARGE HAIL THREAT WILL CONTINUE WITH SUPERCELLS OVER THE NEXT FEW
HOURS.

[KWT]

Here is todays updated outlook, a pretty large zone of slight warnings!

DAY 1 CONVECTIVE OUTLOOK
NWS STORM PREDICTION CENTER NORMAN OK
0100 AM CDT TUE APR 06 2010

VALID 061200Z - 071200Z

...THERE IS A SLGT RISK OF SVR TSTMS FROM OK TO THE MIDWEST/UPPER
GREAT LAKES VICINITY...

...THERE IS A SLGT RISK OF SVR TSTMS ACROSS THE NORTHEAST STATES...

...SYNOPSIS...
A PROGRESSIVE LARGE SCALE REGIME...WITH SPLIT UPPER FLOW ALONG THE
NORTH AMERICAN ROCKIES...WILL EXIST THROUGH THE PERIOD. A
STRENGTHENING SOUTHWESTERLY BELT OF MID/UPPER FLOW...AHEAD OF A
NEUTRAL TO POSITIVE TILT UPPER TROUGH SPREADING EASTWARD FROM THE
ROCKIES TO THE PLAINS...WILL CONTRIBUTE TO A BROAD SPATIAL EXTENT OF
SEVERE POTENTIAL COINCIDENT WITH A MODERATELY MOIST WARM SECTOR
ACROSS THE PLAINS/MIDWEST TO NORTHEAST STATES.

...OK/LOWER MO VALLEY TO MIDWEST/UPPER GREAT LAKES..
ONGOING EARLY DAY STRONG/SEVERE TSTMS WITH MAINLY HAIL POTENTIAL
SEEM LIKELY TO BE ONGOING ACROSS IA/SURROUNDING AREAS TO THE LAKE MI
VICINITY ON THE EDGE OF A STRONG ELEVATED MIXED LAYER. ISOLATED
DAMAGING WIND POTENTIAL CANNOT BE RULED IF ORGANIZED
QUASI-LINEAR/BOWING SYSTEMS PERSIST DURING THE MORNING.

OTHERWISE...THE NORTHWARD PROGRESSION OF THE WARM FRONT ACROSS THE
MIDWEST/UPPER GREAT LAKES VICINITY MAY BE IMPEDED/CONVECTIVELY
REINFORCED BY THE EARLY DAY SHOWERS/TSTMS...BUT OTHERWISE WILL
CONTINUE TO RETREAT A BIT NORTHWARD FROM NORTHERN IL/NORTHERN
INDIANA INTO FAR SOUTHERN WI AND LOWER MI. LOWER 60S F SURFACE
DEWPOINTS WILL BE COMMON ACROSS THE MAJORITY OF THE WARM
SECTOR...WITH THE POSSIBILITY OF WEAKLY CAPPED 1000-2000 J/KG MLCAPE
/ESPECIALLY FROM SOUTHERN IA TO OK/ BY MID/LATE AFTERNOON.

AS THE PARENT UPPER TROUGH CROSSES THE PLAINS AND MID/UPPER FLOW
STRENGTHENS/BACKS...A COLD FRONT SHOULD GRADUALLY OVERTAKE THE
OTHERWISE QUASI-STATIONARY SW-NE ORIENTED FRONT ACROSS THE LOWER MO
RIVER VALLEY. THIS SHOULD LEAD TO SURFACE BASED TSTM DEVELOPMENT
DURING THE AFTERNOON...INITIALLY FROM PORTIONS OF IA TO W/NW MO AND
EASTERN KS. QUASI-DISCRETE SUPERCELLS CAPABLE OF LARGE HAIL/SOME
TORNADOES WILL BE POSSIBLE EARLY IN MODAL EVOLUTIONS THROUGH LATE
AFTERNOON/EARLY EVENING...BUT DEEP LAYER SHEAR LARGELY PARALLEL TO
THE COLD FRONT IMPLIES AN EVENING EVOLUTION TO LINE SEGMENTS WITH
SOME INCREASE IN DAMAGING WIND POTENTIAL.

FARTHER SOUTH FROM SOUTHEAST KS INTO OK...TIMING OF CONVECTIVE
INITIATION AND/OR PROSPECTS FOR NEAR-PEAK HEATING TSTM DEVELOPMENT
IS MORE UNCERTAIN WITH SOUTHWARD EXTENT ACROSS THE DRYLINE.
HOWEVER...AT LEAST A CONDITIONAL-TYPE SEVERE RISK WILL INITIALLY
EXIST GIVEN A RELATIVELY MOIST/WEAKLY CAPPED AND POTENTIALLY
MODERATELY UNSTABLE BOUNDARY LAYER. WITH MID LEVEL FLOW SOMEWHAT
MORE NORMAL TO THE DRYLINE /AS COMPARED TO LOCATIONS FARTHER
NORTHEAST/...QUASI-DISCRETE SUPERCELLS CAPABLE OF LARGE
HAIL/TORNADOES ARE POSSIBLE. TSTM DEVELOPMENT/COVERAGE INCLUDING
SEVERE WILL BE BECOME MORE PROBABLE/GREATER BY EARLY/MID EVENING AS
THE COLD FRONT GRADUALLY OVERTAKES THE DRYLINE ACROSS SOUTHEAST KS
AND OK.

...NORTHEAST STATES...
RELATIVELY COMPLEX SCENARIO ACROSS THE NORTHEAST STATES TODAY
INCLUDING SOUTHERN NY/NORTHERN PA...AND PERHAPS NORTHERN NJ INTO
PORTIONS OF SOUTHERN NEW ENGLAND. EARLY DAY UPSTREAM STORMS /SOME
POSSIBLY STRONG/ MAY SPREAD INTO THE REGION THIS MORNING ON THE NOSE
OF A STRONG WSW LOW LEVEL JET/ELEVATED MOISTURE TRANSPORT REGIME.
ALTHOUGH AN INITIALLY DRY/RELATIVELY STABLE AIRMASS WILL EXIST
ACROSS THE REGION...THE NORTHWARD PROGRESSION OF A WARM
FRONT/ATTENDANT 50S F SURFACE DEWPOINTS AND A WARMING BOUNDARY LAYER
MAY CONTRIBUTE TO A DAYTIME UPSWING AND/OR RENEWED STRONG/SEVERE
DEVELOPMENT ALONG THE SURFACE FRONTAL ZONE. IN ALL...SEVERE
HAIL/DAMAGING WINDS WILL BE THE PRIMARY CONCERNS.

...TX...
INITIALLY WELL SOUTH OF THE UPPER JET AXIS...IT SEEMS PROBABLE THAT
CAPPING WILL LARGELY LIMIT TSTM DEVELOPMENT UNTIL TONIGHT ACROSS
MUCH OF NORTH CENTRAL/NORTHEAST TX TO CENTRAL TX/TX BIG BEND.
GREATEST CONFIDENCE IN ISOLATED TO SCATTERED TSTM DEVELOPMENT /AND
ASSOCIATED SEVERE THREAT/ WILL EXIST THIS EVENING AND ESPECIALLY
OVERNIGHT...AS GRADUAL HEIGHT FALLS OCCUR AND THE COLD FRONT
GRADUALLY OVERTAKES THE DRYLINE/ASSOCIATED MOIST SECTOR. ALTHOUGH A
CATEGORICAL SLIGHT RISK DOES NOT APPEAR TO BE
WARRANTED...STRENGTHENING FLOW ALOFT COUPLED WITH MODERATE
INSTABILITY IMPLIES SEVERE HAIL/PERHAPS DAMAGING WINDS WILL BE
POSSIBLE WITH THE STRONGEST STORMS.

[KWT]

Plus here is the day two risk:

SPC AC 060558

DAY 2 CONVECTIVE OUTLOOK
NWS STORM PREDICTION CENTER NORMAN OK
1258 AM CDT TUE APR 06 2010

VALID 071200Z - 081200Z

...THERE IS A SLGT RISK OF SVR TSTMS FROM THE MIDWEST TO THE WRN
GULF COASTAL REGION...

...SYNOPSIS...
UPR TROUGH EVOLVING OVER THE WRN STATES WILL AMPLIFY OVER THE PLAINS
TUESDAY NIGHT AND THEN MIGRATE INTO THE GRTLKS...MIDWEST AND
LWR/MID-MS VLY BY 12Z THURSDAY. SFC LOW...INITIALLY OVER NCNTRL MO
WILL TRANSLATE INTO SRN ONTARIO DURING THE DAY TUESDAY WITH A CDFNT
SWEEPING SEWD. THE FRONT WILL REACH OH...WRN TN...LA BY EARLY
THURSDAY MORNING. MEANWHILE...A WRMFNT WILL DEVELOP NWD INTO CNTRL
NEW ENGLAND AND CNTRL/NRN NY DURING WEDNESDAY AFTN.

...MIDWEST TO THE WRN GULF COASTAL REGION...
CORRIDOR OF GULF MOISTURE ARCING AROUND THE SFC HIGH OVER THE SWRN
ATLC WILL MAINTAIN A MODESTLY UNSTABLE ENVIRONMENT IN A NARROW ZONE
ALONG/AHEAD OF THE CDFNT ON WEDNESDAY. CINH WILL BE QUITE
ROBUST...BUT APPROACH OF ASCENT TIED WITH THE UPR TROUGH WILL WEAKEN
THE EML. THUS...BANDS OF TSTMS WILL INTENSIFY WITHIN EXISTING
MORNING CONVECTION AND JUST AHEAD OF THE FRONT FROM IL SWWD TO E TX
BY MID-AFTN.

SSWLY DEEP-LAYER FLOW WILL LARGELY BE ALIGNED WITH THE FRONT BUT
CONTAIN STRONG SPEED SHEAR. THUS...WHILE LINEAR STORM MODES WILL BE
FAVORED...EMBEDDED SUPERCELLS WILL BE POSSIBLE ALONG WITH LEWPS/BOWS
WITH DMGG WINDS AND LARGE HAIL. ISOLD TORNADOES WILL BE
POSSIBLE...PARTICULARLY ALONG THE TRACK OF THE SFC LOW OVER PARTS OF
IL NEWD INTO SRN LWR MI AND NRN IND. COMPARATIVELY MORE ROBUST
MOISTURE AND SLIGHTLY HIGHER PROBABILITY FOR LONGER-LIVED DISCRETE
CELLS WILL BE SUPPORTIVE OF TORNADOES ACROSS THE MID-SOUTH SWWD INTO
PARTS OF LA/E TX AS WELL.

STRONGER ACTIVITY WILL LIKELY TRACK ENE INTO THE OH VLY WEDNESDAY
NIGHT WHILE WEAKENING. SVR THREATS WILL CONTINUE ALL NIGHT FARTHER
TO THE S FROM WRN TN SWWD INTO THE LWR MS VLY WHERE HIGH WINDS/HAIL
AND ISOLD TORNADOES WILL BE POSSIBLE.

...S TX...
PRECEDING THE SEWD SURGING CDFNT...BOUNDARY LAYER ACROSS THE REGION
WILL BECOME MODERATELY UNSTABLE OWING TO MID/UPR 60S SFC DEW POINTS
BENEATH STEEP MID-LVL LAPSE RATES. TSTMS WILL LIKELY BUILD SWWD
FROM THE UPR TX COAST SWWD ALONG THE FRONT INTO S TX DURING THE
AFTN. CAP WILL BE AN ISSUE AND STORM COVERAGE SHOULD REMAIN ISOLD.
HOWEVER...DMGG WIND GUSTS/HAIL MAY ACCOMPANY ANY STORM THAT DOES
MANAGE TO BECOME ESTABLISHED.

...CNTRL/NRN NY...
BUILDING HEIGHTS AND INCREASING CINH WILL OCCUR IN ADVANCE OF THE
PLAINS UPR TROUGH ACROSS THE ERN SEABOARD ON WEDNESDAY. CORRIDOR OF
MID-UPR 50S SFC DEW POINTS...EXPECTED HEATING AND LLVL CONVERGENCE
INVOF THE WRMFNT MAY BE SUFFICIENT FOR ISOLD TSTMS ACROSS CNTRL/NRN
NY. SHOULD A STORM FORM...PRESENCE OF STEEP MID-TROPOSPHERIC LAPSE
RATES AND CLOSE PROXIMITY OF 50 KTS OF WLY MID-LVL FLOW WILL BE
FAVORABLE FOR ORGANIZED SVR STORMS. ATTM...STORM COVERAGE IS
EXPECTED TO REMAIN ISOLD.

[srainhoutx]

[srainhoutx]

We will need to keep an eye on E OK to NW IL today for the main action IMHO...







DAY 1 CONVECTIVE OUTLOOK
NWS STORM PREDICTION CENTER NORMAN OK
0758 AM CDT TUE APR 06 2010

VALID 061300Z - 071200Z

...THERE IS A SLGT RISK OF SVR TSTMS THROUGH TONIGHT FOR LOWER MI
WWD TO NRN IL/ERN IA AND MO...ERN KS...ERN OK...

...THERE IS A SLGT RISK OF SVR TSTMS THIS AFTERNOON ACROSS A NARROW
STRIP OF NY/PA INTO WRN MA/CT...

...OH VALLEY/GREAT LAKES TO ERN KS/OK THROUGH TONIGHT...
THE SURFACE CYCLONE IN SE NEB AS OF 12Z WILL PROGRESS GENERALLY
ENEWD TO S CENTRAL IA THIS AFTERNOON AND NW IL OVERNIGHT...ALONG A
SLOW-MOVING WARM FRONT ACROSS SRN IA/NRN IL/LOWER MI AND IN ADVANCE
OF A MIDLEVEL SHORTWAVE TROUGH MOVING EWD FROM CO. DESPITE SOME
APPARENT SUBSIDENCE AND DRYING ACROSS THE LOWER OH/MS VALLEY REGION
PER GOES PW IMAGERY AND REGIONAL SOUNDINGS...A NARROW CORRIDOR OF
BOUNDARY LAYER DEWPOINTS IN THE UPPER 50S TO LOW 60S PERSISTS ALONG
THE STALLED FRONT FROM OH WWD TO SRN IA. SOMEWHAT RICHER MOISTURE
IS PRESENT TO THE E OF THE DRYLINE IN KS/OK...WHERE LOW-MID 60S
DEWPOINTS ARE COMMON. THIS MOISTURE...ALONG WITH DAYTIME
HEATING...WILL AGAIN SUPPORT A NARROW SWATH OF MODERATE INSTABILITY
/MLCAPE VALUES OF 1500-2500 J PER KG/ IN ADVANCE OF THE SURFACE LOW
ACROSS SRN IA/NRN MO/NRN IL...AND IN ADVANCE OF THE DRYLINE ACROSS
ERN KS AND CENTRAL OK THIS AFTERNOON.

THE SHRINKING MOIST SECTOR AND PRESENCE OF A SUBSTANTIAL EML BOTH
SUGGEST THAT DEEP CONVECTION WILL BE FOCUSED IMMEDIATELY ALONG THE
SURFACE BOUNDARIES TODAY. THE ONGOING ELEVATED STORMS OVER NE IL
WILL SPREAD EWD TOWARD SRN LOWER MI...THOUGH SOME WEAKENING IS
EXPECTED LATER THIS MORNING. ADDITIONAL DEVELOPMENT WILL LIKELY BE
DELAYED UNTIL MID-LATE AFTERNOON INVOF THE SURFACE CYCLONE WHERE THE
CAP WILL FIRST WEAKEN. SUBSEQUENT SWD DEVELOPMENT OF STORMS IS
EXPECTED ALONG THE COLD FRONT/DRYLINE ACROSS NW MO AND ERN KS LATE
THIS AFTERNOON...AND LATE THIS EVENING OR EARLY TONIGHT FARTHER S
INTO CENTRAL/ERN OK ALONG THE DRYLINE.

THE MAGNITUDE OF INSTABILITY...IN COMBINATION WITH STRONG DEEP-LAYER
VERTICAL SHEAR /0-6 KM BULK SHEAR OF 50-70 KT/...SHOULD FAVOR
SUPERCELLS WITH THE INITIAL STORM DEVELOPMENT NEAR/E OF THE SURFACE
LOW...AND ALONG THE FRONT/DRYLINE TO THE S. WITH
TIME...HOWEVER...INCREASINGLY LINE-PARALLEL SHEAR VECTORS AND FLOW
ALOFT SHOULD PROMOTE UPSCALE GROWTH INTO LINE SEGMENTS. THE
SEMI-DISCRETE INITIAL CONVECTIVE MODES AND MODEST LOW-LEVEL
SHEAR/MOISTURE WILL CONTRIBUTE TO A THREAT FOR A FEW
TORNADOES...ALONG WITH LARGE HAIL. BY LATE EVENING AND EARLY
OVERNIGHT...THE DAMAGING WIND THREAT WILL BECOME A LITTLE MORE
PROMINENT...BEFORE THE SEVERE THREAT DIMINISHES LATE TONIGHT IN
CONJUNCTION WITH WEAKENING INSTABILITY.

...CENTRAL/SRN NY AND NRN PA TODAY...
A BELT OF ELEVATED CONVECTION ASSOCIATED WITH LOW-LEVEL WAA WILL
CONTINUE TO SPREAD EWD ACROSS ERN PA/CENTRAL NY AND WEAKEN LATER
THIS MORNING. IN THE WAKE OF THIS CONVECTION...SOME LOW-LEVEL
DESTABILIZATION AND NWD RETREAT OF THE BAROCLINIC ZONE WILL
CONTRIBUTE TO A MORE FAVORABLE ENVIRONMENT FOR SURFACE-BASED STORMS
ACROSS NRN PA AND SRN NY TOWARD MIDDAY/AFTERNOON. AN INITIAL SPEED
MAX/REMNANT MCV WILL MOVE OVER NY THIS MORNING...LIKELY BEFORE THE
LOW LEVELS WARM/MOIST SUFFICIENTLY. THIS LEAVES THE ARRIVAL OF
ANOTHER UPSTREAM MCV /NOW OVER NRN IL/ AS A POTENTIAL AID TO
THUNDERSTORM DEVELOPMENT ALONG THE RETREATING BOUNDARY BY LATE
AFTERNOON. IF SURFACE-BASED STORMS DO DEVELOP...INSTABILITY AND
VERTICAL SHEAR WILL BE SUFFICIENT FOR SUPERCELLS AND AT LEAST A
MARGINAL SEVERE HAIL/WIND THREAT.

..THOMPSON/ROGERS.. 04/06/2010

[Dave]

I'll be on between 6 & 10 pm edt tonight but am watching the E OK thru IL throughout the day also. Just checking in for a few right now.

[srainhoutx]

I'll be on between 6 & 10 pm edt tonight but am watching the E OK thru IL throughout the day also. Just checking in for a few right now.

VIS Imagery suggests it may take some time to get going, but worth watching this afternoon/evening.

[Dave]

This watch was issued at 9:30 am EDT this morning...goes until 3 pm edt.



SEVERE THUNDERSTORM WATCH NUMBER 55
NWS STORM PREDICTION CENTER NORMAN OK
930 AM EDT TUE APR 6 2010

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

NORTHERN INDIANA
SOUTHERN LOWER MICHIGAN
LAKE MICHIGAN

EFFECTIVE THIS TUESDAY MORNING AND AFTERNOON FROM 930 AM UNTIL
300 PM EDT.

WIDELY SCATTERED DAMAGING WINDS TO 70 MPH
WIDELY SCATTERED LARGE HAIL TO 2.0 INCHES IN DIAMETER

THE SEVERE THUNDERSTORM WATCH AREA IS APPROXIMATELY ALONG AND 55
STATUTE MILES NORTH AND SOUTH OF A LINE FROM 30 MILES WEST
NORTHWEST OF BENTON HARBOR MICHIGAN TO 10 MILES NORTH OF ANN
ARBOR MICHIGAN. FOR A COMPLETE DEPICTION OF THE WATCH SEE THE
ASSOCIATED WATCH OUTLINE UPDATE (WOUS64 KWNS WOU5).

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 54...

DISCUSSION...CLUSTER OF INTENSE THUNDERSTORMS OVER SOUTHERN LAKE
MICHIGAN WILL TRACK EASTWARD THIS MORNING ACROSS SOUTHERN LOWER MI
AND NORTHERN IND. STORMS ARE MOVING ALONG A SURFACE WARM
FRONT...AND ARE PRIMARILY ELEVATED. THE MAIN THREAT APPEARS TO BE
SEVERE HAIL IN THE STRONGEST CELLS.

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 27045.

[KWT]

Yeah got some severe storms already over MI, however the main area that needs watching (the southern part of the zone) as has been said has a cap in place and so may take some time to get things really going!

[srainhoutx]

SPC keep a Slight Risk, bit upgrades the tornado threat to 10% hatched and an impressive hail threat for NE KS/IA...







DAY 1 CONVECTIVE OUTLOOK
NWS STORM PREDICTION CENTER NORMAN OK
1129 AM CDT TUE APR 06 2010

VALID 061630Z - 071200Z

...THERE IS A SLGT RISK OF SVR TSTMS FROM PARTS OF THE CENTRAL
PLAINS INTO THE UPPER MS VALLEY AND GREAT LAKES...

...THERE IS A SLGT RISK OF SVR TSTMS OVER PARTS OF PA/NY...

A SHORTWAVE TROUGH CURRENTLY DIGGING ACROSS CO/NM WILL TRACK
EASTWARD INTO THE PLAINS TODAY...AND ACROSS THE MS VALLEY TONIGHT.
AS IT DOES SO...SCATTERED SEVERE THUNDERSTORMS ARE EXPECTED TO
DEVELOP ALONG A SURFACE COLD FRONT/DRYLINE FROM IA INTO OK.

...IA/MO/KS...
16Z SURFACE ANALYSIS SHOWS A LOW NEAR OMA WITH WARM FRONT EXTENDING
EASTWARD ACROSS CENTRAL IA...AND COLD FRONT EXTENDING SOUTHWESTWARD
INTO CENTRAL KS. THIS LOW IS EXPECTED TO BE JUST WEST OF DSM BY
LATE THIS AFTERNOON...AND WILL LIKELY BE THE FOCUS FOR RAPID
THUNDERSTORM DEVELOPMENT. FORECAST SOUNDINGS SHOW STRONG EFFECTIVE
SHEAR SUGGESTING SUPERCELL STRUCTURES WILL BE DOMINANT.
THERMODYNAMIC PROFILES ARE ALSO QUITE FAVORABLE FOR LARGE HAIL DUE
TO STEEP MID LEVEL LAPSE RATES AND AMPLE CAPE. STORMS WILL LIKELY
SPREAD INTO EASTERN IA AND NORTHERN IL DURING THE EVENING WITH A
CONTINUED SEVERE THREAT. DUE TO ENHANCED LOW LEVEL SHEAR IN
PROXIMITY OF SURFACE LOW AND WARM FRONT...PARTS OF CENTRAL IA AND
NORTHERN MO HAVE BEEN HIGHLIGHTED WITH 10% PROBABILITY OF TORNADOES.


FARTHER SOUTH...STORMS WILL DEVELOP LATER THIS AFTERNOON ALONG THE
SURFACE COLD FRONT INTO EASTERN KS/WESTERN MO. THESE STORMS WILL
ALSO LIKELY BE SUPERCELLULAR AND TRACK NORTHEASTWARD ACROSS OUTLOOK
REGION WITH A THREAT OF RELATIVELY WIDESPREAD LARGE HAIL. IF
DISCRETE EVOLUTION CAN BE SUSTAINED...ISOLATED TORNADOES WILL BE
POSSIBLE ACROSS THIS REGION AS WELL THROUGH THE EVENING.

...OK...
ALL MODEL GUIDANCE SUGGESTS CONVECTIVE INITIATION WILL BE RETARDED
UNTIL NEAR/AFTER DARK ACROSS OK DUE TO STRONG CAPPING INVERSION.
HOWEVER...LOW LEVEL AND DEEP LAYER VERTICAL SHEAR WILL BE QUITE
FAVORABLE FOR SUPERCELL STRUCTURES ONCE STORMS FORM. STRENGTH OF
CAP SUGGESTS STORMS WILL BE FOCUSED ALONG FRONT/DRYLINE WITH A QLCS
EVOLUTION LIKELY THROUGH THE NIGHT INTO EASTERN OK.

...PA/NY...
A FAST-MOVING MCS OVER LOWER MI HAS BECOME VERY ORGANIZED AT THE
MESOSCALE...AND IS LIKELY TO PERSIST THROUGH THE DAY. THESE STORMS
WILL TRACK EASTWARD ALONG WARM FRONT AND BEGIN AFFECTING WESTERN NEW
YORK BY MID AFTERNOON. IF SUFFICIENT BREAKS IN THE CLOUDS CAN
FORM...THESE STORMS MAY POSE A THREAT OF LARGE HAIL AND DAMAGING
WINDS.

..HART/HURLBUT.. 04/06/2010

[KWT]

Yeah 45% is pretty impressive it has to be said for a slight severe threat, seems to me once again like yesterday at least a risk of an upgrade to moderate if things go bang.

[srainhoutx]

Things are about to get popping...notice the CU development in S Central KS...





MESOSCALE DISCUSSION 0270
NWS STORM PREDICTION CENTER NORMAN OK
0132 PM CDT TUE APR 06 2010

AREAS AFFECTED...PARTS OF ERN KS...NWRN MO INTO SRN IA

CONCERNING...SEVERE POTENTIAL...TORNADO WATCH LIKELY

VALID 061832Z - 061930Z

TORNADO WATCH ISSUANCE WILL BE NEEDED THIS AFTERNOON FROM PARTS OF
ERN KS/NWRN MO INTO SRN IA.

OBJECTIVE ANALYSES INDICATED A RATHER NARROW CORRIDOR OF LOW LEVEL
MOISTURE EXTENDING 75-90 MILES E OF THE DRY LINE. 12Z WRF-NMM 4KM
FORECAST SOUNDINGS SUGGEST THE CAP WILL WEAKEN SUFFICIENTLY FOR
SURFACE BASED STORMS TO DEVELOP BETWEEN 19-20Z ALONG THE DRY LINE IN
SRN-ERN KS TO SWRN-SRN IA. TRENDS IN OBJECTIVE ANALYSES INDICATED
SBCINH WAS ALMOST COMPLETELY DIMINISHED IN THE VICINITY AND E/SE OF
ICT AND ALSO ACROSS NWRN MO/SWRN IA WHICH IS INDICATIVE OF THE
INCREASING CU FIELD ALONG THE DRY LINE IN SRN KS TO NWRN MO AND
CLOSER TO THE SURFACE LOW/WARM FRONT IN SWRN IA. ADDITIONAL SURFACE
HEATING /TEMPERATURES INTO AT LEAST THE MID 80S/ PER MODIFIED 12Z
TOP SOUNDING...CONVERGENCE ALONG THE DRY LINE AND FORCING FOR ASCENT
SPREADING EWD WITH APPROACHING CENTRAL HIGH PLAINS SHORT WAVE TROUGH
SUGGEST TSTMS WILL DEVELOP THIS AFTERNOON.

FORECAST SOUNDINGS E OF THE MOISTURE PLUME SUGGEST THE CAP WILL
REMAIN TOO STRONG TO ALLOW FOR MUCH DEVELOPMENT TOO FAR EAST OF THE
DRY LINE. THUS...GIVEN EXPECTED NEWD STORM MOTION OF 40-50
KT...INITIAL SEVERE WEATHER THREAT AREA SHOULD BE IN A 75-90 MILE
WIDE CORRIDOR ALONG AND E OF THE DRY LINE...WHICH AT 18Z EXTENDED
SWWD FROM A LOW IN SWRN IA THROUGH NERN TO SOUTH CENTRAL KS TO WRN
OK. DEEP LAYER SHEAR VECTORS HAVE GREATER CROSS ANGLE OVER NWRN
MO/SRN IA AND THUS SUGGEST GREATER TORNADO THREAT WITH NWD EXTENT IN
THE DISCUSSION AREA. HOWEVER...TORNADO AND LARGE HAIL THREAT ALSO
EXTENDS SWD INTO SRN KS GIVEN STRENGTH OF DEEP LAYER SHEAR
SUPPORTING SUPERCELLS.

..PETERS.. 04/06/2010


ATTN...WFO...DVN...DMX...EAX...TOP...ICT...

[KWT]

Yeah nice little CU field there, now all it needs is the cap to be broken and things will become severe pretty quickly!

[srainhoutx]

URGENT - IMMEDIATE BROADCAST REQUESTED
SEVERE THUNDERSTORM WATCH NUMBER 56
NWS STORM PREDICTION CENTER NORMAN OK
210 PM CDT TUE APR 6 2010

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

EASTERN KANSAS
WESTERN AND NORTHERN MISSOURI

EFFECTIVE THIS TUESDAY AFTERNOON AND EVENING FROM 210 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 60
STATUTE MILES EAST AND WEST OF A LINE FROM 45 MILES SOUTH
SOUTHEAST OF WICHITA KANSAS TO 45 MILES NORTHWEST OF KIRKSVILLE
MISSOURI. 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 FORM THIS
AFTERNOON OVER ALONG SURFACE COLD FRONT OVER EASTERN KS AND
NORTHWEST MO...AND TRACK NORTHEASTWARD ACROSS WATCH AREA. FAVORABLE
EFFECTIVE SHEAR PROFILES AND SUFFICIENT CAPE WILL PROMOTE A RISK
SUPERCELLS CAPABLE OF LARGE HAIL AND DAMAGING WINDS ALONG THIS ZONE.
VEERED LOW LEVEL WINDS AND RELATIVELY HIGH LCLS SUGGEST THAT
TORNADO THREAT WILL REMAIN QUITE ISOLATED THROUGH THE AFTERNOON AND
EARLY EVENING.

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.


...HART

[srainhoutx]

Storms firing rapidly NW of Wichita, KS...

http://radar.weather.gov/radar.php?rid= ... 1&loop=yes