June 16-19th Plains/MW/GL/OV Severe Weather, SPC Risk Level: Day 1 Slight Risk - Forecasts & OBS Options

[SEMIweather]

Next system...

[snowlover2]

Day 3

DAY 3 CONVECTIVE OUTLOOK
NWS STORM PREDICTION CENTER NORMAN OK
0302 AM CDT TUE JUN 14 2011

VALID 161200Z - 171200Z



...THERE IS A SLGT RISK OF SVR TSTMS ACROSS PARTS OF THE CENTRAL
PLAINS...

...SYNOPSIS...
ALTHOUGH MODELS DIFFER SOMEWHAT WITH THE AMPLIFICATION OF A TROUGH
OVER THE ERN STATES...GENERAL AGREEMENT EXISTS WITH THE TIMING OF A
COUPLE OF EMBEDDED SHORTWAVE TROUGHS EXPECTED TO TRACK EWD ACROSS
THE MID ATLANTIC STATES THIS FORECAST PERIOD. MEANWHILE...HEIGHTS
ARE EXPECTED TO RISE UPSTREAM FROM THE LOWER MO TO UPPER MS VALLEYS
AS FURTHER AMPLIFICATION OCCURS WITH THE WRN TROUGH.

IN THE LOW LEVELS...A SURFACE LOW AND TRAILING COLD FRONT WILL
SPREAD EWD FROM THE OH/TN VALLEY...REACHING IN LEE OF THE CENTRAL
AND SRN APPALACHIANS BY 12Z FRIDAY. FARTHER W...A LEE CYCLONE WILL
DEEPEN ACROSS SERN CO BENEATH SWLY FLOW ALOFT AND THEN MOVE INTO WRN
KS THURSDAY NIGHT.



...PARTS OF THE CENTRAL PLAINS...
SLY LOW LEVEL FLOW EAST OF THE CO CYCLONE WILL SPREAD MOISTURE NWD
ACROSS THE PLAINS AND ALSO INTO THE MID MS VALLEY...WITH WNWWD
MOISTURE ADVECTION INTO WRN NEB/NERN CO. PLUME OF STEEP MIDLEVEL
LAPSE RATES/EML EXTENDING ACROSS THE MOISTURE RETURN WILL SUPPORT A
CORRIDOR OF STRONG INSTABILITY EXTENDING FROM CENTRAL/ERN OK/KS TO
THE CENTRAL DAKOTAS THURSDAY AFTERNOON...WITH WEAKER INSTABILITY
INTO THE NERN CO/WRN NEB.

UPSLOPE FLOW ALONG THE NRN PERIPHERY OF THE CO SURFACE LOW AND
FORCING FOR ASCENT ATTENDANT TO A MIDLEVEL IMPULSE INDICATED BY THE
14/00Z ECMWF SUGGESTS AFTERNOON TSTM DEVELOPMENT WILL BE POSSIBLE
OVER NERN CO/SERN WY INTO WRN NEB. DESPITE WEAKER INSTABILITY...
VERY STEEP MIDLEVEL LAPSE RATES AND EFFECTIVE BULK SHEAR OF 40-55 KT
WILL PROVE FAVORABLE FOR HIGH BASED SUPERCELLS. UPSCALE GROWTH OF
THE HIGH PLAINS ACTIVITY IS POSSIBLE AS LOW LEVEL WAA INCREASES
ACROSS THE CENTRAL PLAINS...WITHIN THE NOSE OF A STRENGTHENING
CENTRAL/SRN PLAINS SLY LLJ. THUS...THE SLIGHT RISK EXTENDS EWD TO
ACCOUNT FOR MAINLY ELEVATED STORMS PRODUCING HAIL AND SOME STRONGER
WIND GUSTS AS THE MIDLEVEL IMPULSE PROGRESSES TOWARD ERN NEB TO SRN
MN LATE IN THE PERIOD.

[wsushox1]

look sgood.

[snowlover2]

New day 2- Only plains threat should be discussed here on this day.

DAY 2 CONVECTIVE OUTLOOK
NWS STORM PREDICTION CENTER NORMAN OK
0104 AM CDT WED JUN 15 2011

VALID 161200Z - 171200Z

...THERE IS A SLGT RISK OF SVR TSTMS FROM CENTRAL/SERN VA TO
ERN/SERN GA...

...THERE IS A SLGT RISK OF SVR TSTMS ACROSS PARTS OF THE CENTRAL
PLAINS...

...SYNOPSIS...
MODELS ARE IN BETTER AGREEMENT WITH THE TRACK AND EVOLUTION OF THE
CURRENT NRN PLAINS SHORTWAVE TROUGH FOR THE DAY 2 PERIOD... WITH
THIS SYSTEM MOVING FROM THE WRN GREAT LAKES TO THE UPPER OH
VALLEY/CENTRAL APPALACHIANS BY 12Z FRIDAY. MEANWHILE...A COUPLE OF
MIDLEVEL SHORTWAVE TROUGHS WILL EJECT NEWD FROM THE BASE OF A
LONGWAVE TROUGH CONTINUING TO DEVELOP ACROSS THE FULL EXTENT OF THE
WRN STATES. THESE IMPULSES SHOULD REACH THE CENTRAL/NRN HIGH PLAINS
BY LATE THURSDAY AFTERNOON AND THEN PROCEED ACROSS THE DAKOTAS AND
CENTRAL PLAINS THURSDAY NIGHT. BETWEEN THE E AND W TROUGHS...A
RIDGE WILL BUILD NWD FROM THE LOWER MO VALLEY TO UPPER MS VALLEY/WRN
GREAT LAKES.

IN THE LOW LEVELS...A SURFACE LOW AND TRAILING COLD FRONT WILL
SPREAD EWD FROM THE OH/TN VALLEYS...WITH THE FRONT MOVING EAST OF
THE CENTRAL/SRN APPALACHIANS BY 17/00Z. FARTHER W...A LEE CYCLONE
WILL DEEPEN ACROSS ERN CO BENEATH SWLY FLOW ALOFT AND THEN MOVE INTO
WRN/CENTRAL KS THURSDAY NIGHT. MEANWHILE...A SURFACE FRONT EXPECTED
TO STALL FROM THE MID SOUTH WWD TO NORTH TX DURING DAY 1 WILL LIFT
NWD THURSDAY AS A WARM FRONT. THIS BOUNDARY SHOULD REACH NRN KS TO
SRN MO BY LATE THURSDAY AFTERNOON.

...MID-ATLANTIC AND SERN STATES...
A WEAKENING LEAD IMPULSE SHOULD BE MOVING ACROSS THE MID-ATLANTIC
STATES/DELMARVA REGION DURING THE EARLY PART OF DAY 2...WITH NEUTRAL
TO WEAK HEIGHT RISES IN ITS WAKE THROUGH THURSDAY AFTERNOON.
SHOWERS AND EMBEDDED TSTMS ARE FORECAST TO TRACK ACROSS MD/VA/DEL
AND NC THURSDAY MORNING/EARLY AFTERNOON...AND SHOULD TEND TO LIMIT
STRONGER DESTABILIZATION ACROSS THESE AREAS. MEANWHILE... SSWLY LOW
LEVEL WINDS WILL SPREAD MOISTURE NWD IN LEE OF THE SRN/CENTRAL
APPALACHIANS. THIS COMBINED WITH SURFACE HEATING IN THE WAKE OF
MORNING ACTIVITY AND AHEAD OF THE APPROACHING COLD FRONT SHOULD
SUPPORT A NARROW CORRIDOR OF MODERATE INSTABILITY FROM CENTRAL VA
INTO WRN NC...AND SWD ACROSS THE SERN STATES.

EFFECTIVE BULK SHEAR SHOULD BE STRONGER /UP TO 35 KT/ ACROSS VA/NC
SUPPORTIVE FOR POTENTIAL SUPERCELLS...WHILE FARTHER S...BULK SHEAR
SHOULD BE MORE FAVORABLE FOR MULTICELLS ACROSS SC/GA. GIVEN THESE
FACTORS COMBINED WITH SOME UNCERTAINTY IN DEGREE OF DESTABILIZATION
WITH NWD EXTENT DUE TO EARLY DAY CONVECTIVE CLOUDINESS...15 PERCENT
SEVERE PROBABILITIES WILL BE MAINTAINED WITH THIS OUTLOOK ISSUANCE.

...PLAINS STATES TO THE LOWER MO VALLEY...
SLY LOW LEVEL FLOW WILL RETURN MOISTURE NWD THROUGH THE CENTRAL
PLAINS TO THE MID MO VALLEY AND NEWD INTO THE LOWER MO/MID MS
VALLEYS. THIS MOISTURE COMBINED WITH DIABATIC HEATING BENEATH A
PLUME OF VERY STEEP MIDLEVEL LAPSE RATES EXTENDING NEWD ACROSS THE
PLAINS STATES TO LOWER MO VALLEY WILL RESULT IN STRONGLY UNSTABLE
AIR MASS. MLCAPE 2000-3000 J/KG IS EXPECTED TO EXTEND FROM NRN AR
NWWD INTO NRN KS TO SRN SD.

UPSLOPE FLOW ALONG THE NRN PERIPHERY OF THE CO SURFACE LOW AND
FORCING FOR ASCENT ATTENDANT TO A MIDLEVEL IMPULSE SUGGEST AFTERNOON
TSTM DEVELOPMENT WILL BE POSSIBLE OVER NERN CO INTO CENTRAL/ERN WY
AND THE NEB PANHANDLE. DESPITE WEAKER INSTABILITY WITH WWD
EXTENT...VERY STEEP MIDLEVEL LAPSE RATES AND EFFECTIVE BULK SHEAR OF
40-55 KT WILL PROVE FAVORABLE FOR HIGH BASED SUPERCELLS. UPSCALE
GROWTH OF THE HIGH PLAINS ACTIVITY IS POSSIBLE AS LOW LEVEL WAA
INCREASES ACROSS THE CENTRAL PLAINS...WITHIN THE NOSE OF A RATHER
BROAD STRENGTHENING CENTRAL/SRN PLAINS SLY LLJ. THUS...THE SLIGHT
RISK ALSO EXTENDS EWD TO ACCOUNT FOR OVERNIGHT ELEVATED STORMS
PRODUCING HAIL AND SOME STRONGER WIND GUSTS AS THE MIDLEVEL IMPULSE
PROGRESSES TOWARD ERN NEB TO SRN MN LATE IN THE PERIOD. A FEW
MODELS SUGGEST A SEPARATE TSTM INITIATION AREA ACROSS NRN KS/ERN NEB
WITH THIS ACTIVITY SPREADING INTO IA/SRN MN THURSDAY NIGHT. DEGREE
OF INSTABILITY AND DEEP LAYER SHEAR WILL SUPPORT A SEVERE THREAT
WITH THIS ACTIVITY.

...PARTS OF THE OH VALLEY...
FORCING FOR ASCENT ATTENDANT TO THE SHORTWAVE TROUGH AND EXIT REGION
OF ACCOMPANYING 50 KT WNWLY MIDLEVEL JET TRACKING ESEWD ACROSS THIS
REGION ON THURSDAY SHOULD SUPPORT TSTM DEVELOPMENT WITHIN A
MARGINALLY UNSTABLE ENVIRONMENT. WEAK MIDLEVEL LAPSE RATES AND SOME
RESIDUAL MOISTURE FROM DAY 1 COMBINED WITH DIABATIC HEATING SHOULD
RESULT IN MLCAPE OF 500-1000 J/KG. EFFECTIVE BULK SHEAR OF 30-35 KT
SUGGESTS A FEW ORGANIZED STORMS WILL BE POSSIBLE...THOUGH WEAK
INSTABILITY SHOULD LIMIT OVERALL SEVERE WEATHER THREAT.

[Gilbertfly]

not sure if this goes into this thread or the 19th+ thread. . .

LOT. . .

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE CHICAGO/ROMEOVILLE IL
334 PM CDT WED JUN 15 2011

.DISCUSSION...
328 PM CDT

BY FRIDAY NIGHT HOWEVER...DEEP CLOSED LOW OVER SRN SASKATCHEWAN WILL
ESTABLISH A BROAD SWLY LOW-MID LEVEL FLOW ACROSS THE PLAINS AND INTO
THE MID/UPPER MS VALLEY. AS THIS TAKES PLACE...A LINGERING FRONTAL
BOUNDARY FROM THE CENTRAL PLAINS...EWD THROUGH THE UPPER OH VALLEY
WILL BEGIN TO MOVE NWD AS A WARM FRONT. THIS INCREASING SURGE OF
TROPICAL AIR WILL AID IN THE DEVELOPMENT OF YET ADDITIONAL ROUNDS OF
ELEVATED THUNDERSTORMS AND CONVECTIVE COMPLEXES. THERE CONTINUES TO
BE SOME MODEL DIFFERENCES REGARDING THE TIMING OF WARM FRONTAL
PASSAGE OVER THE WEEKEND. THE GFS IS THE MOST AGGRESSIVE ON
BRINGING THIS FRONT THROUGH NRN IL/NWRN INDIANA...WHILE THE NAM/EURO
SOLUTIONS KEEP ELY SURFACE-BOUNDARY LAYER FLOW GOING THROUGH AT
LEAST SUNDAY. REGARDLESS OF THIS FRONTAL POSITION...WILL CONTINUE
A MENTION OF THUNDERSTORMS FROM FRIDAY NIGHT THROUGH THE EXTENDED
PERIOD. IF GFS TURNS OUT TO BE CORRECT...WE WILL BREAK INTO
TROPICAL AIR...BUT BE VERY UNSTABLE THROUGH THE PERIOD TO THE
POINT THAT A RANDOM SNEEZE MAY SET OFF THUNDERSTORMS. IF THE OTHER
SOLUTIONS ARE MORE ACCURATE...THEN WE WILL REMAIN IN A ZONE OF
STRONGER LOW LEVEL MOISTURE CONVERGENCE AND AN ONGOING RISK OF
MORE ORGANIZED THUNDERSTORM COMPLEXES. THE VARIATIONS IN MODEL
FORECAST FRONTAL POSITION PRESENT MORE INCONSISTENCY/UNCERTAINTY
IN MAX TEMPERATURE FORECASTS AS OPPOSED TO THE PRECIPITATION
OUTLOOK.

MERZLOCK

[snowlover2]

New day 1 - Plains threat only here


Tornado


Hail


Wind

DAY 1 CONVECTIVE OUTLOOK
NWS STORM PREDICTION CENTER NORMAN OK
1258 AM CDT THU JUN 16 2011

VALID 161200Z - 171200Z

...THERE IS A SLGT RISK OF SVR TSTMS TODAY AND TONIGHT ACROSS PARTS
OF THE CENTRAL PLAINS INTO THE MID/LOWER MISSOURI VALLEY REGION...

...THERE IS A SLGT RISK OF SVR TSTMS TODAY ACROSS PARTS OF THE UPPER
OHIO VALLEY AND MID ATLANTIC STATES...

...SYNOPSIS...
MODELS INDICATE LITTLE CHANGE TO THE LARGE-SCALE FEATURES WITHIN THE
PREVAILING SPLIT UPPER FLOW IMPACTING NORTH AMERICA THROUGH THIS
FORECAST PERIOD. WITHIN ONE BRANCH OF STRONGER FLOW TRAVERSING THE
NORTHERN AND CENTRAL TIER OF THE U.S...A BROAD CLOSED LOW APPEARS
LIKELY TO LINGER NEAR THE NORTHERN ROCKIES. BUT A SIGNIFICANT SHORT
WAVE IMPULSE IS PROGGED TO MIGRATE AROUND THE SOUTHERN PERIPHERY OF
ITS CIRCULATION CENTER...DIGGING ACROSS THE NORTHERN INTERMOUNTAIN
REGION DURING THE DAY...BEFORE TURNING EASTWARD INTO THE ROCKIES
TONIGHT. DOWNSTREAM...ANOTHER MUCH MORE COMPACT CLOSED LOW IS
EXPECTED PROGRESS ACROSS SOUTHERN PORTIONS OF THE GREAT LAKES
REGION...TOWARD THE UPPER OHIO VALLEY...TO THE SOUTH OF A YET
ANOTHER CLOSED LOW SHIFTING SOUTH SOUTHWESTWARD TOWARD SOUTHERN
HUDSON/JAMES BAY. FARTHER SOUTH...HIGH-LEVEL TROUGHING PROBABLY
WILL PERSIST OVER MUCH OF THE SOUTHEAST AND GULF OF MEXICO...BETWEEN
SUBTROPICAL HIGH CENTERS OVER THE NORTHERN MEXICAN PLATEAU AND OVER
THE LOWER LATITUDE ATLANTIC.

...CENTRAL PLAINS INTO MID/LWR MISSOURI VALLEY...
GUIDANCE CONTINUES TO SUGGEST THAT AN IMPULSE EMERGING FROM THE
WESTERN TROUGH MAY CONTRIBUTE TO INCREASING CONVECTIVE DEVELOPMENT
BY THE 15-18Z TIME FRAME...BASED WITHIN A ZONE OF ENHANCED LOWER/MID
TROPOSPHERIC WARM ADVECTION ACROSS NORTH CENTRAL AND NORTHEAST
KANSAS. THIS IS EXPECTED TO OCCUR COINCIDENT WITH A RETURN FLOW OF
MOISTURE NOW PRESENT ALONG AND SOUTH OF A WEAKENING FRONT ACROSS THE
RED RIVER VALLEY/OZARKS PLATEAU REGION. IN THE PRESENCE OF
MODERATELY STRONG SHEAR BENEATH 30-40 NORTHWESTERLY 500 MB
FLOW...POTENTIAL APPEARS TO EXIST FOR AN ORGANIZING MESOSCALE
CONVECTIVE SYSTEM BY MID DAY NEAR THE KANSAS CITY AREA...ON THE EDGE
OF VERY WARM...AND MORE STRONGLY CAPPING...ELEVATED MIXED LAYER AIR
ADVECTING ACROSS THE CENTRAL/SOUTHERN PLAINS. AS THE BOUNDARY LAYER
ACROSS THE MISSOURI OZARKS DESTABILIZES WITH MOISTURE
ADVECTION...DAYTIME HEATING AND STEEPENING MID-LEVEL LAPSE RATES...A
SIGNIFICANT CONVECTIVELY GENERATED COLD POOL MAY DEVELOP WITH A RISK
FOR STRONG DAMAGING WINDS. AS THIS ACTIVITY DEVELOPS SOUTHEASTWARD
THROUGH PARTS OF CENTRAL/SOUTHERN MISSOURI...A TRAILING OUTFLOW
BOUNDARY INTO PARTS OF SOUTHEAST AND CENTRAL KANSAS MAY REMAIN A
FOCUS FOR NEW STORM DEVELOPMENT...PARTICULARLY TONIGHT...AS A STRONG
SOUTHERLY LOW-LEVEL JET DEVELOPS ACROSS THE PLAINS.

ELSEWHERE...FORCING DOWNSTREAM OF THE MAIN UPPER IMPULSE OVER THE
INTERMOUNTAIN WEST MAY CONTRIBUTE TO ADDITIONAL STRONG/SEVERE STORM
DEVELOPMENT BY LATE THIS AFTERNOON...WITHIN A MOISTENING AND
DESTABILIZING UPSLOPE BOUNDARY LAYER FLOW ACROSS THE NORTH CENTRAL
HIGH PLAINS. VEERING WINDS WITH HEIGHT...FROM EASTERLY AT LOWER
LEVELS TO MODESTLY STRONG SOUTHWESTERLY AT MID-LEVELS... SHOULD
PROVIDE SUFFICIENT SHEAR FOR SUPERCELLS INITIALLY. UPSCALE GROWTH
INTO A MESOSCALE CONVECTIVE SYSTEM THEN APPEARS LIKELY THIS
EVENING...AS ACTIVITY DEVELOPS EASTWARD ACROSS WESTERN
NEBRASKA...AIDED BY STRONG INFLOW OF AIR WITH CAPE OF 2000-3000+
J/KG. THIS PROBABLY WILL BE ACCOMPANIED BY A SIGNIFICANT COLD POOL
WITH STRONG DAMAGING WIND GUSTS.

OTHER MORE ISOLATED STRONG/SEVERE STORM DEVELOPMENT MAY ALSO OCCUR
LATE THIS AFTERNOON AND EVENING ALONG THE DRY LINE ACROSS PARTS OF
WESTERN KANSAS INTO THE TEXAS/OKLAHOMA PANHANDLE REGION...WHERE A
HOT AND DEEPLY MIXED BOUNDARY LAYER WILL BE SUPPORTIVE OF STRONG
DOWNBURSTS...PERHAPS SOME HAIL.

[snowlover2]

New day 2

DAY 2 CONVECTIVE OUTLOOK
NWS STORM PREDICTION CENTER NORMAN OK
0103 AM CDT THU JUN 16 2011

VALID 171200Z - 181200Z

...THERE IS A SLGT RISK OF SVR TSTMS FROM ERN PARTS OF THE
NRN/CENTRAL PLAINS SEWD THROUGH THE OH VALLEY...

...THERE IS A SLGT RISK OF SVR TSTMS ACROSS PART OF THE MID-ATLANTIC
STATES...

...SYNOPSIS...
AN OMEGA BLOCK UPPER AIR PATTERN WILL PERSIST FROM THE NRN EXTENT OF
THE U.S. AND CANADA...WITH ATTENDANT CLOSED LOWS CENTERED OVER WRN
CANADA AND QUEBEC. GRADUAL HEIGHT RISES ARE EXPECTED FROM THE LOWER
MS VALLEY NEWD INTO THE OH VALLEY TO MID-ATLANTIC STATES.
A SHORTWAVE TROUGH...CURRENTLY TRACKING SSEWD THROUGH WA/ORE PER
WATER VAPOR IMAGERY...WILL ROTATE THROUGH THE BASE OF THE WRN CLOSED
LOW ON DAY 1 AND EMERGE FROM THE NRN HIGH PLAINS...TRACKING NNEWD
ACROSS THE DAKOTAS ON FRIDAY. IN THE EAST...A SHORTWAVE TROUGH
LOCATED OVER THE UPPER OH VALLEY/CENTRAL APPALACHIANS AT THE START
OF DAY 2 SHOULD WEAKEN/DE-AMPLIFY AS THIS PROGRESSIVE FEATURE
REACHES THE MID-ATLANTIC COAST BY EARLY FRIDAY EVENING.
MEANWHILE...WEAK PERTURBATIONS SHOULD MOVE ESEWD FROM THE MIDWEST
THROUGH THE OH VALLEY.

...PARTS OF CENTRAL/NRN PLAINS TO UPPER MS VALLEY...
SLY LOW LEVEL WINDS EXTENDING INTO THE DAKOTAS WILL SUPPORT NWD
MOISTURE RETURN BENEATH THE NRN EXTENSION OF STEEP MIDLEVEL LAPSE
RATES EXTENDING ACROSS THE MID MO TO UPPER MS VALLEYS. THIS WILL
CONTRIBUTE TO MODERATE TO VERY STRONG INSTABILITY ACROSS THE
CENTRAL/NRN PLAINS BY FRIDAY AFTERNOON.

AREAS OF ELEVATED TSTMS WILL LIKELY BE ONGOING FROM THE NRN PLAINS
SEWD INTO THE MIDWEST ALONG AND N OF A WARM FRONT AND WITHIN A LOW
LEVEL WAA REGIME. PERSISTENT WAA ALONG THE N/NEWD ADVANCING WARM
FRONT SHOULD SUPPORT CONTINUED CONVECTION SPREADING N/NEWD ACROSS
THE UPPER MS VALLEY.

FORCING FOR ASCENT ATTENDANT TO THE SHORTWAVE TROUGH MOVING ACROSS
THE DAKOTAS AND CONVERGENCE ALONG A COLD FRONT ADVANCING EWD THROUGH
THE NRN/CENTRAL PLAINS ARE EXPECTED TO SUPPORT NEW TSTM DEVELOPMENT
ALONG THE COLD AND WARM FRONTS...POSSIBLY AS FAR S AS ERN KS TO OK.
STRONG SHEAR VECTORS ORIENTED PARALLEL TO THE COLD FRONT SUGGESTS
ACTIVITY WILL TEND TO BE LINEAR...THOUGH SUPERCELLS WILL BE
POSSIBLE. A STRENGTHENING LLJ INTO THE MID-UPPER MS VALLEY SUGGESTS
UPSCALE GROWTH INTO ONE OR MORE MCS/S APPEARS LIKELY AS THE COLD
FRONT PROGRESSES EWD INTO THE UPPER MS AND LOWER MO VALLEYS. SOME
ACTIVITY MAY REMAIN SEVERE GIVEN MODERATE ELEVATED INSTABILITY.

...MID MS VALLEY SEWD THROUGH OH/TN VALLEYS...
A WARM FRONT AND RETURNING LOW LEVEL MOISTURE ARE EXPECTED TO SPREAD
NEWD INTO THIS REGION BENEATH THE EWD EXTENSION OF STEEP MIDLEVEL
LAPSE RATES. SOME MODEL UNCERTAINTY CONTINUES ACROSS IL/IND/OH ON
FRIDAY WITH RESPECT TO HOW FAR NE THE WARM FRONT REACHES AND THE
OVERALL DEGREE OF DESTABILIZATION DUE TO THE LIKELIHOOD FOR ONGOING
CONVECTION/TSTMS FRIDAY MORNING N/NE OF THE FRONT. HOWEVER...GIVEN
A NWLY FLOW REGIME ACROSS THIS REGION AND THE 12Z ECMWF/00Z GFS
INDICATING A MIDLEVEL IMPULSE MOVING THROUGH THE RIDGE ACROSS THE
MIDWEST AND OH VALLEY...CONFIDENCE IS HIGHER FOR GREATER STORM
COVERAGE FRIDAY AFTERNOON. MODERATE-VERY STRONG INSTABILITY SHOULD
DEVELOP ACROSS IL/IND /MLCAPE OF 2000-3000 J PER KG/ AND MODERATE
INSTABILITY ACROSS OH/KY. A 40-50 KT WNWLY MIDLEVEL JET
ACCOMPANYING THE IMPULSE INTO WILL RESULT IN EFFECTIVE BULK SHEAR
INCREASING TO 35-40 KT SUPPORTIVE OF ORGANIZED STORMS. SHEAR
VECTORS ORIENTED MORE PARALLEL TO THE WARM FRONT SUGGEST LINE
SEGMENTS SHOULD BE THE PRIMARY MODE...THOUGH SUPERCELLS WILL BE
POSSIBLE. GIVEN THESE FACTORS...A SLIGHT RISK AREA HAS BEEN
INTRODUCED WITH PRIMARY THREATS BEING DAMAGING WINDS AND HAIL.

[snowlover2]

New day 3

DAY 3 CONVECTIVE OUTLOOK
NWS STORM PREDICTION CENTER NORMAN OK
0240 AM CDT THU JUN 16 2011

VALID 181200Z - 191200Z

...THERE IS A SLGT RISK OF SVR TSTMS EXTENDING FROM THE NRN AND
CENTRAL HIGH PLAINS EWD THROUGH THE MID MS/OH VALLEYS TO THE LOWER
GREAT LAKES AND PA...

...SYNOPSIS...
A BLOCKING PATTERN EXTENDING FROM THE NWRN STATES AND ACROSS CANADA
WILL PERSIST INTO DAY 3 /SAT/. THE CLOSED LOW OVER ERN CANADA WILL
SHIFT SSEWD ACROSS QUEBEC TOWARD NRN NEW ENGLAND. MEANWHILE...IN
THE WEST A CLOSED LOW WILL RETROGRADE NWWD ACROSS SASKATCHEWAN/
ALBERTA AS A TROUGH DIGS SEWD ACROSS THE PACIFIC NW TO THE GREAT
BASIN...MAINTAINING THE LONGWAVE TROUGH OVER THE WRN STATES. WITH
MORE OF A FLAT RIDGE EXPECTED ACROSS THE SRN HALF OF THE CONUS BY
SATURDAY...MID-UPPER LEVEL FLOW FROM THE SWRN STATES TO THE OH
VALLEY AND MID-ATLANTIC STATES SHOULD BECOME GENERALLY WSWLY.

AT 12Z SATURDAY...MODELS ARE IN GENERAL AGREEMENT INDICATING A WARM
FRONT EXTENDING WNWWD FROM OH TO AN AREA OF LOW PRESSURE LOCATED
OVER ERN IA/NRN IL. A COLD FRONT SHOULD BE TRAILING SWWD FROM THE
LOW THROUGH ERN KS TO THE SRN HIGH PLAINS. THE SURFACE LOW SHOULD
MOVE EWD THROUGH THE OH VALLEY/SRN GREAT LAKES REGION WITH THE COLD
FRONT ADVANCING SLOWLY SEWD INTO THE OH AND MID MS VALLEYS.
MEANWHILE...THE WARM FRONT WILL MOVE EWD REACHING THE LOWER GREAT
LAKES TO MID-ATLANTIC STATES BY 12Z SUNDAY.

...LOWER MO/MID MS VALLEYS TO OH VALLEY/SRN GREAT LAKES...
SWLY LOW LEVEL WINDS ACROSS THE WARM SECTOR AND BENEATH A PLUME OF
STEEP MIDLEVEL LAPSE RATES SPREADING THROUGHOUT MUCH OF THIS REGION
WILL SUPPORT THE DEVELOPMENT OF MODERATE-VERY STRONG INSTABILITY
FROM THE UPPER OH VALLEY WSWWD TO KS/OK. THE STRONGEST INSTABILITY
SHOULD RESIDE FROM THE MID MS VALLEY INTO ERN KS/NERN OK WITH MLCAPE
OF 2500-3500 J/KG. MODELS SUGGEST SEVERAL MIDLEVEL IMPULSES SHOULD
TRAVERSE THE OH VALLEY/GREAT LAKES ON SATURDAY AIDING IN NEW TSTM
DEVELOPMENT WITHIN THE MOIST/UNSTABLE ENVIRONMENT. EFFECTIVE BULK
SHEAR SHOULD BE GREATEST FROM THE UPPER OH VALLEY INTO PA AND LOWER
GREAT LAKES WHERE ORGANIZED STORMS WILL BE POSSIBLE. ALTHOUGH BULK
SHEAR WILL BE WEAKER WITH WWD EXTENT INTO THE LOWER OH TO LOWER MO
VALLEYS...THE DEGREE OF INSTABILITY AND STEEP LAPSE RATES SUGGEST
SOME STORMS COULD BECOME SEVERE.

...CENTRAL/NRN HIGH PLAINS EWD ACROSS NEB/KS...
DESPITE GENERALLY WEAK LOW LEVEL MOISTURE RETURN INTO THE HIGH
PLAINS OF ERN CO TO SERN MT...STEEP MIDLEVEL LAPSE RATES AND STRONG
SURFACE HEATING ALONG A DEVELOPING LEE TROUGH WILL RESULT IN
MODERATE INSTABILITY /MLCAPE AROUND 1000 J PER KG/. MODELS TEND TO
AGREE WITH THE A MIDLEVEL IMPULSE OR TWO SPREADING NEWD ACROSS THE
CENTRAL/NRN HIGH PLAINS BY 19/00Z PROVIDING FORCING FOR ASCENT FOR
TSTM DEVELOPMENT. EFFECTIVE BULK SHEAR OF 40-50 KT COMBINED WITH
THE STEEP LAPSE RATE ENVIRONMENT SUGGESTS SUPERCELLS WILL BE
POSSIBLE. MODELS SUGGEST STORMS WILL MOVE OFF THE HIGHER TERRAIN
INTO THE WRN DAKOTAS...WITH GREATEST UPSCALE GROWTH INTO AN MCS OR
TWO ACROSS THE CENTRAL PLAINS WHERE INSTABILITY WILL BE STRONGER
INTO SATURDAY NIGHT TO MAINTAIN SOME SEVERE WEATHER THREAT.

[WEATHERNUT09]

The write up by SPC sounds promising for severe storms for southern Great Lakes region.

[SADBadger]

The write up by SPC sounds promising for severe storms for southern Great Lakes region.

not before 6PM on Saturday, please! It's Chicago Highland Games and I don't own a band cape! Not to mention we're in an open area and drones tend to be pretty high over one's head...

I'll wait and see what the new Day 2 will be tomorrow.

[The Snowman]

GEFS Probs of 4000+ CAPE above 90% tomorrow around 7 pm...

Attached thumbnail(s)

 

[Illinois blizzar...]

BULLETIN - EAS ACTIVATION REQUESTED
TORNADO WARNING
NATIONAL WEATHER SERVICE DODGE CITY KS
829 PM CDT THU JUN 16 2011

THE NATIONAL WEATHER SERVICE IN DODGE CITY HAS ISSUED A

* TORNADO WARNING FOR...
NORTH CENTRAL COMANCHE COUNTY IN SOUTH CENTRAL KANSAS...
SOUTHERN KIOWA COUNTY IN SOUTH CENTRAL KANSAS...

* UNTIL 900 PM CDT

* AT 824 PM CDT...NATIONAL WEATHER SERVICE DOPPLER RADAR INDICATED
VERY STRONG ROTATION ASSOCIATED WITH A POSSIBLE TORNADO 9 MILES
SOUTHEAST OF MULLINVILLE. THIS DANGEROUS STORM WAS MOVING SOUTHEAST
AT 30 MPH.

* LOCATIONS IMPACTED INCLUDE...
HAVILAND...WELLSFORD...WILMORE AND BELVIDERE.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

TAKE COVER NOW. MOVE TO AN INTERIOR ROOM ON THE LOWEST FLOOR OF A
STURDY BUILDING. AVOID WINDOWS. IF IN A MOBILE HOME...A VEHICLE OR
OUTDOORS...MOVE TO THE CLOSEST SUBSTANTIAL SHELTER AND PROTECT
YOURSELF FROM FLYING DEBRIS.

TO REPORT SEVERE WEATHER...CONTACT YOUR NEAREST LAW ENFORCEMENT
AGENCY. THEY WILL RELAY YOUR REPORT TO THE NATIONAL WEATHER SERVICE
IN DODGE CITY.

&&

[snowlover2]

New day 1


Tornado


Hail


Wind

DAY 1 CONVECTIVE OUTLOOK
NWS STORM PREDICTION CENTER NORMAN OK
1241 AM CDT FRI JUN 17 2011

VALID 171200Z - 181200Z

...THERE IS A SLGT RISK OF SVR TSTMS TODAY AND TONIGHT ACROSS THE
MID/LOWER MISSOURI AND MIDDLE MISSISSIPPI VALLEYS...

...SYNOPSIS...
MODELS INDICATE THAT A VIGOROUS SHORT WAVE IMPULSE WILL BECOME THE
PRIMARY LOW CENTER AS IT LIFTS NORTH OF THE NORTHERN ROCKIES THROUGH
SOUTHERN SASKATCHEWAN DURING THIS FORECAST PERIOD. BROADER SCALE
TROUGHING...WITHIN WHICH THIS FEATURE IS EMBEDDED...LIKELY WILL
PERSIST ACROSS MUCH OF THE WESTERN U.S...WHILE CONTINUING TO DEVELOP
EASTWARD THROUGH MUCH OF THE NORTHERN PLAINS. AS THIS OCCURS...AND
ANOTHER CLOSED LOW DIGS TO THE SOUTHEAST OF JAMES BAY...A REMNANT
DOWNSTREAM MID-LEVEL CIRCULATION IS EXPECTED TO MIGRATE ACROSS
NORTHERN MID ATLANTIC AND SOUTHERN NEW ENGLAND COASTAL AREAS.
MEANWHILE...MID-LEVEL SUBTROPICAL RIDGING MAY BECOME A BIT MORE
PROMINENT ACROSS THE SOUTHERN TIER STATES...BUT WEAK HIGH-LEVEL
TROUGHING PROBABLY WILL LINGER OVER THE EASTERN GULF OF
MEXICO...BETWEEN AN EXPANDING HIGH CENTER OVER THE MEXICAN
PLATEAU/RIO GRANDE VALLEY AND ANOTHER OVER THE LOWER LATITUDE
ATLANTIC.

...MID/LWR MISSOURI AND MIDDLE MISSISSIPPI VALLEYS...
AHEAD OF A WEAK COLD FRONT ADVANCING INTO THE NORTHERN AND CENTRAL
PLAINS...AND NORTH/EAST OF A DEEP THERMAL LOW CENTER OVER THE SOUTH
CENTRAL PLAINS...A MOIST BOUNDARY LAYER WITH 70F+ SURFACE DEW POINTS
IS EXPECTED TO OVERSPREAD THE REGION. THIS APPEARS LIKELY TO OCCUR
COINCIDENT WITH THE EASTWARD ADVECTION OF VERY WARM ELEVATED MIXED
LAYER AIR...AT LEAST AS FAR EAST AS THE MID AND LOWER MISSOURI
VALLEY REGION BY EARLY THIS AFTERNOON. AND A BROAD AREA OF MODERATE
TO STRONG INSTABILITY IS EXPECTED TO DEVELOP BY PEAK AFTERNOON
HEATING. MIXED LAYER CAPE PROBABLY WILL REACH 2000-4000 J/KG...WITH
HIGHEST VALUES CENTERED ACROSS PARTS OF EASTERN KANSAS INTO WESTERN
AND CENTRAL MISSOURI.

MID-LEVEL FORCING TO FOCUS STRONGER CONVECTIVE DEVELOPMENT REMAINS
UNCLEAR...BUT A BROAD LOW/MID-LEVEL WARM ADVECTION REGIME BENEATH
BROADLY DIFLUENT UPPER FLOW SEEMS LIKELY TO PROVIDE SUPPORT FOR
CONVECTIVE DEVELOPMENT. AND MOMENTUM/SHEAR ASSOCIATED WITH A BROAD
BELT OF 30-40+ KT SOUTHWESTERLY 500 MB FLOW NOSING ACROSS THE
CENTRAL PLAINS AND MID MISSOURI VALLEY...AS WELL AS A 30-40 KT
SOUTHERLY LOW-LEVEL JET FROM THE SOUTHERN PLAINS INTO THE LOWER
MISSOURI VALLEY...PROBABLY WILL CONTRIBUTE TO THE EVOLUTION OF
ORGANIZED MESOSCALE CONVECTIVE SYSTEMS CAPABLE OF PRODUCING DAMAGING
WIND GUSTS AND HAIL.

THE DETAILS OF THE CONVECTIVE EVOLUTION REMAIN FAR FROM CERTAIN.
HOWEVER...IT APPEARS POSSIBLE THAT A REMNANT IMPULSE OR MESOSCALE
CONVECTIVE VORTEX...ASSOCIATED WITH THE LARGE ONGOING CONVECTIVE
CLUSTER ACROSS THE MID MISSOURI VALLEY...COULD PROVIDE THE FOCUS FOR
NEW DEVELOPMENT THIS AFTERNOON FROM PARTS OF EASTERN
NEBRASKA/WESTERN IOWA INTO NORTHERN MISSOURI. ADDITIONAL
DEVELOPMENT MAY THEN OCCUR LATE THIS AFTERNOON AND EVENING ON ITS
WESTERN FLANK...ACROSS EASTERN KANSAS INTO WESTERN MISSOURI...AS
ANOTHER IMPULSE EMERGING FROM THE INTERMOUNTAIN WEST WEAKENS STRONG
INHIBITION ACROSS THE CENTRAL PLAINS.

[snowlover2]

New day2 - SE KS/NE OK to OV threat only. Western plains i believe is the begining of the next system.

DAY 2 CONVECTIVE OUTLOOK
NWS STORM PREDICTION CENTER NORMAN OK
1255 AM CDT FRI JUN 17 2011

VALID 181200Z - 191200Z

...THERE IS A SLGT RISK OF SVR TSTMS FROM PORTIONS OF OK/KS EWD INTO
THE OH VALLEY...

...THERE IS A SLGT RISK OF SVR TSTMS ACROSS PORTIONS OF THE NRN AND
CENTRAL HIGH PLAINS...

...SYNOPSIS...
A BLOCKING UPPER RIDGE FROM THE GREAT LAKES REGION NWWD INTO THE
CENTRAL CANADIAN PROVINCES WILL MAINTAIN A BROAD TROUGH OVER MOST OF
THE WRN/CENTRAL CONUS AND ANOTHER TOUGH ACROSS THE NERN STATES. THE
WRN/CENTRAL U.S TROUGH WILL FLATTEN THE RIDGE ACROSS THE SOUTH
STATES AND RESULT IN RELATIVELY STRONG WSWLY MID LEVEL WINDS FROM
THE CENTRAL ROCKIES/PLAINS EWD THROUGH THE OH VALLEY AND INTO NEW
ENGLAND. IN ASSOCIATION WITH THE TWO UPPER TROUGHS ...A WEAK COLD
FRONT IS FORECAST TO STRETCH FROM NEW ENGLAND SWWD THROUGH THE
OH/MID MS VALLEYS AND INTO CENTRAL OK/SRN TX PANHANDLE LATE SATURDAY
AFTERNOON.

...OH VALLEY REGION...
OPERATIONAL MODELS ARE SUGGESTIVE THAT AN MCS MAY BE LOCATED OVER
PORTIONS OF MO/IL AT THE START OF THE PERIOD...WITHIN ZONE OF LOW
LEVEL WARM ADVECTION. THIS ACTIVITY IS LIKELY TO SPREAD EWD THROUGH
THE OH VALLEY DURING THE DAY AND EITHER REINTENSIFY OR NEW STORMS
DEVELOP ALONG THE FRONT AND OUTFLOW BOUNDARIES. IN AREAS WHERE
STRONG HEATING OCCURS...THE COMBINATION OF DEWPOINTS IN THE UPPER
60S/LOWER 70S AND STEEP MID LEVEL LAPSE RATES WILL RESULT IN A VERY
UNSTABLE AIR MASS. GIVEN THAT THE EFFECTIVE BULK SHEAR WILL BE IN
THE 25-35 KT RANGE WITH MOSTLY UNIDIRECTIONAL WLY WINDS...A LINEAR
MCS OR TWO IS POSSIBLE WITH WIND DAMAGE THE PRIMARY SEVERE THREAT.

...OK/KS/MO AREA...
STORMS/CLOUDS ARE EXPECTED TO SHIFT EWD OUT OF MO IN THE MORNING
...WHICH SHOULD RESULT IN STRONG HEATING OF MOIST BOUNDARY
LAYER...ESPECIALLY NEAR THE FRONT IN KS/OK. MODELS INDICATE
THAT THE COMBINATION OF TEMPERATURE NEAR 100 AND DEWPOINTS IN THE
MID 60S WILL RESULT IN EXTREME INSTABILITY. HOWEVER...VERY WARM MID
LEVEL TEMPERATURES...14 TO 16C AT 700 MB... ARE EXPECTED TO INHIBIT
CONVECTION THROUGH MUCH OF THE DAY. HOWEVER...00Z NAM/GFS BOTH SHOW
THE SRN END OF A SHORTWAVE TROUGH MOVING THROUGH WRN KS/TX PANHANDLE
LATE IN THE DAY. FORCING AHEAD OF THIS FEATURE AND FRONTAL
CONVERGENCE MAY BE ENOUGH FOR HIGH BASED STORMS TO DEVELOP LATE IN
THE DAY...ESPECIALLY AS TEMPERATURES CLIMB ABOVE 100 DEGREES. MID
LEVEL WLY WINDS AT 35-45 KT WILL HELP ORGANIZE/SUSTAIN STORMS AND A
VERY FAVORABLE THERMODYNAMIC ENVIRONMENT WILL EXIST FOR HAIL AND
SEVERE WIND GUSTS...SOME WIND GUSTS WHICH MAY BE SIGNIFICANT. STORMS
MAY SPREAD OR REDEVELOP DURING THE EVENING INTO SRN MO AS THE UPPER
TROUGH SHIFTS EWD AND THE LOW LEVEL JET STRENGTHENS...WITH A
CONTINUED THREAT FOR WIND DAMAGE AND HAIL.

[snowlover2]

New day 3 - Believe OV threat is still part of this thread.

DAY 3 CONVECTIVE OUTLOOK
NWS STORM PREDICTION CENTER NORMAN OK
0223 AM CDT FRI JUN 17 2011

VALID 191200Z - 201200Z

...THERE IS A SLGT RISK OF SVR TSTMS FROM THE NRN/CENTRAL PLAINS EWD
THROUGH INTO THE MID MS AND OH VALLEYS...

...SYNOPSIS...
IMPRESSIVE SHORTWAVE TROUGH AND ASSOCIATED JET MAX ARE FORECAST TO
MOVE DOWN THE BACKSIDE OF THE WRN U.S UPPER TROUGH...RESULTING IN
THE LARGER SCALE TROUGH TO AMPLIFY WEST OF THE ROCKIES.
CONSEQUENTLY...IN AGREEMENT WITH GFS/EURO SOLUTIONS...SHORTWAVE
RIDGING AND STRONGER MID LEVEL WLY FLOW WILL BE PUSHED NWD ACROSS
THE PLAINS STATES...AND EXTEND FROM NM NEWD INTO KS/NEB AND THEN EWD
THROUGH THE LOWER OH VALLEY AND INTO THE MID ATLANTIC STATES. IN
RESPONSE TO THE AMPLIFYING UPPER TROUGH...SURFACE LOW PRESSURE
SHOULD DEVELOP IN ERN CO...WITH A WARM/STATIONARY FRONT EXTENDING
EWD ACROSS KS THROUGH SRN MO AND INTO THE OH VALLEY.

...MID MS AND OH VALLEY REGION...
SWLY LOW LEVEL JET IS FORECAST TO IMPINGE UPON FRONT ACROSS SRN
MO...WITH CONVECTION LIKELY TO BE ONGOING OVER PORTIONS OF ERN MO
EWD INTO INDIANA SUNDAY MORNING. WHILE THE SHEAR AND INSTABILITY
WOULD SUPPORT A MARGINAL SEVERE THREAT...THE STORMS SHOULD INTENSIFY
DURING THE AFTERNOON AS WARMING TEMPERATURES RESULT IN STRONGLY
UNSTABLE AIR MASS. THE DEEP WLY TROPOSPHERIC WINDS AND 30-40 KT MID
LEVEL FLOW SHOULD FAVOR AN ORGANIZED LINE OR TWO WITH WIND DAMAGE
THE MOST LIKELY THREAT.

[melissa from ill...]

Those storms in MO are lookin robust this morning!

[CentralIllinois]

HAZARDOUS WEATHER OUTLOOK
NATIONAL WEATHER SERVICE LINCOLN IL
601 AM CDT FRI JUN 17 2011

ILZ027-028-030-038-042>046-048-051>057-061>063-066>068-071>073-
181100-
CHAMPAIGN-CHRISTIAN-CLARK-CLAY-COLES-CRAWFORD-CUMBERLAND-DE WITT-
DOUGLAS-EDGAR-EFFINGHAM-JASPER-KNOX-LAWRENCE-LOGAN-MACON-MARSHALL-
MCLEAN-MENARD-MOULTRIE-PIATT-RICHLAND-SANGAMON-SHELBY-STARK-
VERMILION-
601 AM CDT FRI JUN 17 2011

THIS HAZARDOUS WEATHER OUTLOOK IS FOR PORTIONS OF CENTRAL
ILLINOIS...EAST CENTRAL ILLINOIS AND SOUTHEAST ILLINOIS.

.DAY ONE...TODAY AND TONIGHT

A WARM MOIST AIRMASS WILL INTERACT WITH A WARM FRONT TO THE WEST TO
BRING THUNDERSTORMS TO THE AREA FOR LATE THIS AFTERNOON AND TONIGHT.
THERE IS A SLIGHT RISK THAT SOME OF THESE STORMS COULD BECOME
SEVERE WITH DAMAGING WINDS AND LARGE HAIL.

.SPOTTER INFORMATION STATEMENT...

SPOTTER ACTIVATION MAY BE NEEDED LATER THIS AFTERNOON AND INTO
TONIGHT.

[SADBadger]

HAZARDOUS WEATHER OUTLOOK...UPDATED
NATIONAL WEATHER SERVICE MILWAUKEE/SULLIVAN WI
738 AM CDT FRI JUN 17 2011

WIZ046-047-051-052-056>060-062>072-181015-
MARQUETTE-GREEN LAKE-FOND DU LAC-SHEBOYGAN-SAUK-COLUMBIA-DODGE-
WASHINGTON-OZAUKEE-IOWA-DANE-JEFFERSON-WAUKESHA-MILWAUKEE-
LAFAYETTE-GREEN-ROCK-WALWORTH-RACINE-KENOSHA-
738 AM CDT FRI JUN 17 2011

THIS HAZARDOUS WEATHER OUTLOOK IS FOR PORTIONS OF EAST CENTRAL
WISCONSIN...SOUTH CENTRAL WISCONSIN AND SOUTHEAST WISCONSIN.

.DAY ONE...TODAY AND TONIGHT

PATCHY DENSE FOG IS EXPECTED TO LINGER ACROSS EASTERN
SHEBOYGAN...OZAUKEE AND MILWAUKEE COUNTIES UNTIL MID MORNING.

THERE IS A CHANCE OF THUNDERSTORMS THIS AFTERNOON SOUTHWEST OF
MADISON...AS AN UPPER LEVEL DISTURBANCE CROSSES THE REGION.
THUNDERSTORMS BECOME LIKELY TONIGHT FROM WEST TO EAST ACROSS THE
AREA...AS A WARM FRONT MOVES NORTH TOWARD THE AREA...AND ANOTHER
UPPER LEVEL DISTURBANCE CROSSES THE REGION.

THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS TONIGHT...MAINLY
SOUTHWEST OF A MINERAL POINT TO MONROE LINE. LARGE HAIL...DAMAGING
WINDS AND HEAVY RAINFALL WOULD BE POSSIBLE IN THIS AREA...AS A
POSSIBLE COMPLEX OF THUNDERSTORMS MOVES ACROSS THE REGION.

.DAYS TWO THROUGH SEVEN...SATURDAY THROUGH THURSDAY

CHANCES FOR THUNDERSTORMS WILL CONTINUE AT TIMES SATURDAY THROUGH
THURSDAY...AS THE WARM FRONT SLOWLY MOVES NORTH TOWARD AND THROUGH
THE AREA. SEVERAL UPPER LEVEL DISTURBANCES ARE EXPECTED TO SHIFT
ACROSS THE REGION DURING THIS TIME.

THE BEST CHANCES FOR THUNDERSTORMS WOULD BE SATURDAY...AS A
POSSIBLE THUNDERSTORM COMPLEX MOVES THROUGH THE REGION...AND
TUESDAY NIGHT...AS A COLD FRONT MOVES THROUGH. IF THE COMPLEX
MOVES THROUGH ON SATURDAY...HEAVY RAINFALL WOULD BE POSSIBLE.

.SPOTTER INFORMATION STATEMENT...

SPOTTER ACTIVATION MAY BE NEEDED TONIGHT SOUTHWEST OF MADISON...AND
AT TIMES LATER THIS WEEKEND INTO NEXT WEEK ACROSS THE AREA.

[WeatherMonger]

Cloud cover really needs to move out, but not looking likely.

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE LINCOLN IL
1134 AM CDT FRI JUN 17 2011

.DISCUSSION...
ISSUED 1123 AM CDT FRI JUN 17 2011
MINOR TWEAKS TO THE FORECAST TO COVER FOR THE PRECIP SHIELD AND
WEATHER ADVANCING FROM THE WEST. STILL CONCERN FOR AFTERNOON
THUNDERSTORMS...WITH IMPRESSIVE LAPSE RATES ON 12Z SOUNDING. THAT
BEING SAID...SHEAR IS MINIMAL AND SFC BASED INSTABILITY IS GETTING
LIMITED BY CLOUD COVER/PRECIP SHIELD FROM APPROACHING CONVECTION.
OUTFLOW FROM STORMS WILL HAVE TO BE WATCHED CLOSELY FOR ANY
AFTERNOON CONVECTION AHEAD OF THE WARM FRONT THIS EVENING.


HJS

[snowlover2]

Updated day 2(OV only)

DAY 2 CONVECTIVE OUTLOOK CORR 1
NWS STORM PREDICTION CENTER NORMAN OK
1235 PM CDT FRI JUN 17 2011

VALID 181200Z - 191200Z

...THERE IS A SLGT RISK OF SVR TSTMS ACROSS THE NRN AND CNTRL HIGH
PLAINS...KS/OK...AND THE MID MS VALLEY INTO THE OH/TN VALLEYS...

CORRECTED FOR GRAPHIC

...SYNOPSIS...
AN UPPER RIDGE OVER THE MO/MS VALLEY REGION WILL FLATTEN THROUGH THE
DAY AND SHIFT EWD A BIT AS MULTIPLE EMBEDDED SHORTWAVES ALOFT MOVE
INTO THE PLAINS. ONE SUCH SHORTWAVE TROUGH WILL MOVE FROM NM NEWD
ACROSS THE TX/OK PANHANDLES DURING THE DAY AND ACROSS KS/OK AND INTO
WRN MO BY SUN MORNING. ANOTHER WAVE WILL MOVE ACROSS WY/CO AND INTO
NEB DURING THE AFTERNOON AND EVENING.

AT THE SURFACE...A WEAK COLD FRONT WILL EXTEND FROM ERN KS INTO THE
TX PANHANDLE...WITH A DRYLINE EXTENDING SWWD FROM A WRN OK LOW INTO
TX. AS THE UPPER WAVES APPROACH...THE COOL AIR BEHIND THE OLD FRONT
WILL MIX AND WINDS WILL VEER TO ELY OVER KS...ALLOWING MOISTURE TO
BACK WWD AND RESULTING IN A WARM FRONT NEAR THE KS/OK BORDER.
MEANWHILE...A SHARP DRYLINE WILL EXIST ALONG THE I-35 CORRIDOR FROM
THE KS/OK BORDER SWD INTO NRN TX. BOTH THESE FEATURES WILL BE THE
FOCUS FOR SEVERE STORMS.

TO THE N...WEAK LEE TROUGHING WILL EXTEND NWD INTO WY...WRN SD AND
NEB BY AFTERNOON...HELPING TO FOCUS CONVECTION IN THIS AREA AS WELL.


TO THE E...MODERATE NWLY FLOW ALOFT WILL EXIST ON THE E SIDE OF THE
RIDGE AXIS ACROSS THE OH AND TN VALLEYS...WITH SIGNS OF WEAK
EMBEDDED FEATURES POSSIBLY ASSOCIATED WITH ONGOING CONVECTION.


...OH/TN VALLEY REGION...
CONSIDERABLE UNCERTAINTY EXISTS IN REGARD TO PLACEMENT AND EVOLUTION
OF MORNING CONVECTION...BUT CONSENSUS IS THAT A POSSIBLE MCS WILL BE
ONGOING OVER IND...KY...AND SWRN OH SAT MORNING...TIED TO A POSSIBLE
SHORTWAVE TROUGH ROUNDING THE RIDGE AND FORCED ON THE NOSE OF A SWLY
LOW LEVEL JET. THESE STORMS WILL HAVE MAINLY A WIND THREAT...AND MAY
REGENERATE/STRENGTHEN DURING THE DAY WITH AREAS OF HEATING TO THE S.
THERE MAY ALSO BE A MARGINAL HAIL THREAT ESPECIALLY ON THE SRN AND
WRN FLANK OF ANY STORM CLUSTER...IN CLOSE PROXIMITY TO BETTER LOW
LEVEL LAPSE RATES AND THUS STRONGER UPDRAFTS.