[SWODY2] SWODY2

[Severe Weather Outlook - Day 2]

ACUS02 KWNS 190538
SWODY2
SPC AC 190537

DAY 2 CONVECTIVE OUTLOOK  
NWS STORM PREDICTION CENTER NORMAN OK
1237 AM CDT MON JUN 19 2006

VALID 201200Z - 211200Z

...THERE IS A SLGT RISK OF SVR TSTMS TUE/TUE NIGHT ACROSS PARTS OF
THE N CNTRL PLAINS INTO THE UPPER GREAT LAKES REGION....

MODELS CONTINUE TO INDICATE LITTLE CHANGE TO THE LARGE-SCALE PATTERN
THROUGH THIS FORECAST PERIOD AND BEYOND.  A SPLIT FLOW REGIME WILL
PERSIST IN THE HIGHER LATITUDES...WITH THE SOUTHERN BELT REMAINING
GENERALLY ZONAL ALONG/OR JUST SOUTH OF THE CANADIAN/U.S. BORDER. 
WITHIN THIS STREAM...A SERIES OF BROADER SCALE TROUGHS ARE FORECAST
TO REMAIN PROGRESSIVE TUESDAY. THIS INCLUDES ONE PROGGED TO SHIFT
EAST OF THE LOWER GREAT LAKES INTO NORTH ATLANTIC COASTAL
AREAS...AND ANOTHER PROGGED EASTWARD ALONG THE CENTRAL CANADIAN/U.S.
BORDER.

...N CNTRL PLAINS THRU THE UPPER GREAT LAKES REGION...
STRONG DESTABILIZATION STILL APPEARS LIKELY BY EARLY TUESDAY ACROSS
THE NORTH CENTRAL PLAINS/MID MISSOURI VALLEY REGION...WHERE BOUNDARY
LAYER IS FORECAST TO MOISTEN CONSIDERABLY...BENEATH CAPPING
MID-LEVEL THERMAL RIDGE NOSING NORTHEASTWARD OUT OF THE
CENTRAL/SOUTHERN ROCKIES.  SURFACE DEW POINTS ARE EXPECTED TO CLIMB
THROUGH THE LOWER/MID 60S AS MID-LEVEL LAPSE RATES STEEPEN.  THIS
WILL CONTRIBUTE TO STRONG CONDITIONAL AND CONVECTIVE
INSTABILITY...WHICH SHOULD YIELD MIXED LAYER CAPE ON THE ORDER OF
2000 TO 4000 J/KG BY PEAK HEATING TUESDAY AFTERNOON.

VIGOROUS CONVECTIVE DEVELOPMENT COULD BE ONGOING AT 12Z TUESDAY IN
FAVORABLE LOW/MID-LEVEL WARM ADVECTION REGIME ON NORTHERN/EASTERN
PERIPHERY OF STRONGER CAP...FROM PARTS OF THE DAKOTAS SOUTHEASTWARD
INTO IOWA.  THIS ACTIVITY IS EXPECTED TO DEVELOP EASTWARD AND WEAKEN
THROUGH THE DAY.  THE FOCUS FOR PRIMARY CONVECTIVE DEVELOPMENT
DURING THE LATE AFTERNOON...THEN...IS EXPECTED TO BE FORCING EAST OF
WEAK FRONTAL WAVE...FORMING ON THE SOUTHERN FRINGE OF THE STRONGER
WESTERLIES.  THIS APPEARS MOST LIKELY FROM PARTS OF EASTERN NEBRASKA
INTO CENTRAL IOWA.

MODELS STILL INDICATE SEASONABLY STRONG WIND FIELDS WILL ACCOMPANY
UPPER TROUGH THROUGH THE MID MISSOURI VALLEY...WITH THE NOSE OF A
30-40 KT SOUTHERLY LOW-LEVEL JET FORECAST BENEATH 40-50 KT WESTERLY
MID-LEVEL FLOW...NEAR/EAST OF SURFACE WAVE.  GIVEN PRESENCE OF LARGE
CAPE...AND THERMODYNAMIC PROFILES SUPPORTING POTENTIAL FOR STRONG
EVAPORATIVE COOLING NEAR HEAVY PRECIPITATION CORES...CONDITIONS SEEM
LIKELY TO FAVOR RAPID TRANSITION FROM SUPERCELLS TO AN EXPANDING
SEVERE MESOSCALE CONVECTIVE SYSTEM... BENEATH RELATIVELY WEAK BUT
DIVERGENT UPPER FLOW.  STRONG DAMAGING WINDS AND LARGE HAIL ARE
EXPECTED...AND A SIGNIFICANT COLD POOL COULD DEVELOP TUESDAY EVENING
AS ACTIVITY SPREADS ACROSS THE CORN BELT INTO THE UPPER MISSISSIPPI
VALLEY.  THIS COULD REACH THE UPPER GREAT LAKES REGION WITH
CONTINUING SEVERE POTENTIAL BY THE END OF THE FORECAST PERIOD.

FARTHER TO THE SOUTH/WEST...MODELS ARE SUGGESTIVE THAT AN IMPULSE IN
THE SUBTROPICAL STREAM COULD WEAKEN INHIBITION SUFFICIENTLY FOR
INITIATION OF CONVECTION NEAR FRONT/PRE-FRONTAL TROUGH ACROSS
EASTERN COLORADO INTO CENTRAL KANSAS BY EARLY TUESDAY EVENING. IF
THIS OCCURS...ANOTHER CLUSTER OF STORMS PROBABLY WILL EVENTUALLY
EVOLVE IN ENVIRONMENT FAVORABLE FOR DOWNBURSTS AND SOME HAIL.

...SOUTHERN MID ATLANTIC COASTAL AREAS INTO NEW ENGLAND...
STRONGER LOW-LEVEL FLOW FIELDS ARE PROGGED TO LIFT AWAY FROM NORTH
ATLANTIC COASTAL AREAS BY EARLY TUESDAY...WITH AN ASSOCIATED TONGUE
OF HIGHER PRECIPITABLE WATER GENERALLY SHIFTING OFFSHORE. 
HOWEVER...LINGERING LOW-LEVEL MOISTURE MAY SUPPORT SUFFICIENT
DESTABILIZATION WITH DAYTIME HEATING FOR LOCALIZED HAIL/WIND EVENTS
IN SCATTERED AFTERNOON THUNDERSTORMS.  ACTIVITY IS EXPECTED TO
DEVELOP AHEAD OF MID-LEVEL TROUGH AXIS...NEAR SURFACE FRONT
ADVANCING TOWARD COASTAL NEW ENGLAND AND THE LOWER HUDSON
VALLEY...AND NEAR LEE SURFACE TROUGH ACROSS MIDDLE/NORTHERN ATLANTIC
COASTAL AREAS.

..KERR.. 06/19/2006