National Weather Service Raw Text Product

777 
ACUS01 KWNS 111304
SWODY1
SPC AC 111302

DAY 1 CONVECTIVE OUTLOOK  
NWS STORM PREDICTION CENTER NORMAN OK
0702 AM CST WED NOV 11 2015

VALID 111300Z - 121200Z

...THERE IS AN ENH RISK OF SVR TSTMS ACROSS PORTIONS OF IA/MO/IL...

...THERE IS A SLGT RISK OF SVR TSTMS FROM THE MO VALLEY/MIDWEST
SOUTHWARD TO THE ARKLATEX...

...THERE IS A MRGL RISK OF SVR TSTMS SURROUNDING THE ENH/SLGT RISK
AREAS...

...SUMMARY...
STRONG TO SEVERE THUNDERSTORMS ARE EXPECTED TO DEVELOP DURING THE
AFTERNOON ACROSS PARTS OF THE MISSOURI VALLEY SOUTH-SOUTHWESTWARD
INTO EASTERN TEXAS. THE GREATEST CONCENTRATION OF POTENTIALLY SEVERE
STORMS THIS AFTERNOON AND EVENING SHOULD EXIST ACROSS PARTS OF IOWA
AND NORTHERN MISSOURI INTO NORTHERN AND CENTRAL ILLINOIS.

...SYNOPSIS...
A DEEP UPPER TROUGH CENTERED OVER THE CENTRAL/SOUTHERN ROCKIES AND
ADJACENT HIGH PLAINS EARLY THIS MORNING WILL ACCELERATE
EAST-NORTHEASTWARD OVER THE PLAINS TODAY AND REACH THE UPPER GREAT
LAKES BY LATE TONIGHT/EARLY THURSDAY. THIS SYSTEM IS BEING
ACCOMPANIED BY VERY STRONG DEEP-TROPOSPHERIC FLOW...HIGHLIGHTED BY A
100-130 KT MID/HIGH-LEVEL SOUTHWESTERLY JET WITH AN INCREASINGLY
STRONG /50-75 KT/ LOW-LEVEL JET INTO TONIGHT. 

STEADY SURFACE CYCLOGENESIS WILL CONTINUE TO OCCUR OVER KS EARLY
TODAY...WITH THE SURFACE LOW DEEPENING NORTHEASTWARD INTO IA/WI THIS
AFTERNOON AND EVENING. A COLD FRONT ACROSS THE SOUTH-CENTRAL PLAINS
EARLY TODAY WILL ACCELERATE GENERALLY EASTWARD...REACHING THE OH/TN
RIVER VALLEYS AND LOWER MS VALLEY/COASTAL TX LATE TONIGHT/EARLY
THURSDAY.

...MO VALLEY/MIDWEST INCLUDING IA/MO/IL/SOUTHERN WI...
IN SPITE OF AMPLE MOISTURE FLUXES TODAY...MARGINAL MOISTURE QUALITY
INTO THE REGION SHOULD PRECLUDE WHAT WOULD OTHERWISE LIKELY BE A
MORE CONSEQUENTIAL SEVERE WEATHER RISK IN THE PRESENCE OF ROBUST
FORCING FOR ASCENT/VERTICAL SHEAR. NONETHELESS...SEVERE
THUNDERSTORMS INCLUDING THE POTENTIAL FOR WIND DAMAGE AND A FEW
TORNADOES CAN BE EXPECTED THIS AFTERNOON INTO TONIGHT WITHIN A
HIGHLY SHEARED/WEAKLY UNSTABLE ENVIRONMENT. 

WITH THE LOW-LEVEL MOIST AXIS EXTENDING FROM OK INTO EAST-CENTRAL
KS/NORTHWEST MO EARLY THIS MORNING...A NARROW CORRIDOR OF 50S F
SURFACE DEWPOINTS WILL BECOME INCREASINGLY ESTABLISHED THIS
AFTERNOON ACROSS THE REGION...RESULTING IN A MODESTLY MOIST/UNSTABLE
WARM SECTOR NEAR/AHEAD OF THE DEEPENING SURFACE CYCLONE AND THE
EASTWARD-ACCELERATING COLD FRONT. VARIOUS CONVECTION-ALLOWING MODELS
SUCH AS EARLY-MORNING HRRR/HRRR-ESRL RUNS AND 00Z WRF-NSSL SUGGEST
THAT INITIAL SURFACE-BASED STRONG TO SEVERE THUNDERSTORM
DEVELOPMENT...LIKELY AS SEMI-DISCRETE LOW-TOPPED STORMS...MAY OCCUR
AS EARLY AS NOON-2PM CST NEAR THE MISSOURI RIVER ACROSS
SOUTHWEST/SOUTH-CENTRAL IA AND NORTHERN MO. LOW-LEVEL
MOISTURE/BUOYANCY IN THE PRESENCE OF 200+ 0-1 KM SRH SHOULD BE
SUFFICIENT FOR A FEW TORNADOES ASIDE FROM SOME HAIL/WIND DAMAGE THIS
AFTERNOON.

STORMS SHOULD CONTINUE TO INCREASE/RACE EAST-NORTHEASTWARD ACROSS
IA/PARTS OF MO AND INTO IL/SOUTHERN WI...EVOLVING INTO FAST-MOVING
BANDS OF CONVECTION POSING AN INCREASING POTENTIAL FOR DAMAGING
WINDS BY LATE AFTERNOON/EVENING. EVEN WHILE SURFACE-ROOTED BUOYANCY
WILL BECOME LIMITED/SCANT TONIGHT AND LIGHTNING WILL GRADUALLY
DECREASE...INCREASINGLY INTENSE TROPOSPHERIC FLOW...ACCENTUATED BY
60-75 KT SOUTH-SOUTHWESTERLY WINDS WITHIN THE LOWEST 2-3 KM
AGL...SUGGESTS THAT THE POTENTIAL FOR A FEW DAMAGING WIND GUSTS MAY
PERSIST INTO THE LATE EVENING/OVERNIGHT HOURS...POSSIBLY AS FAR
EAST-NORTHEAST AS PORTIONS OF THE GREAT LAKES/UPPER OH VALLEY.

...MID-SOUTH/OZARKS/ARKLATEX/EAST TX...
ISOLATED/WIDELY SCATTERED THUNDERSTORMS MAY BEGIN TO
DEVELOP/GRADUALLY INTENSIFY BY EARLY/MID-AFTERNOON...INITIALLY
WITHIN A CORRIDOR SPANNING FAR SOUTHERN MO...FAR SOUTHEAST OK...AND
WESTERN/CENTRAL AR SOUTHWESTWARD TO NORTHEAST/EAST TX. THIS
DEVELOPMENT SHOULD OCCUR WITHIN A MODESTLY MOIST/UNSTABLE
PRE-FRONTAL WARM SECTOR AMID WEAK LOW-LEVEL CONFLUENCE. EFFECTIVE
BULK SHEAR OF 40-55 KT WOULD SUPPORT SOME SUPERCELLS. WHILE WINDS IN
THE 1-3 KM AGL LAYER WILL BE TENDING TO VEER THIS
AFTERNOON...SUFFICIENT SPEED SHEAR COULD YIELD A TORNADO ASIDE FROM
ISOLATED WIND DAMAGE. WHILE A FEW INSTANCES OF SEVERE HAIL MAY BE
POSSIBLE THROUGH MID/LATE AFTERNOON...THE OVERALL HAIL POTENTIAL
SHOULD BE TEMPERED BY WEAK MID-LEVEL LAPSE RATES.

..GUYER/MARSH.. 11/11/2015

$$