SPC AC 051729
DAY 2 CONVECTIVE OUTLOOK
NWS STORM PREDICTION CENTER NORMAN OK
1229 PM CDT THU JUN 05 2008
VALID 061200Z - 071200Z
...THERE IS A MDT RISK OF SVR TSTMS ACROSS SOUTHEAST WI/FAR EASTERN
IA/EASTERN MO/NORTHERN AND CENTRAL IL/NORTHERN IND/SOUTHWEST LOWER
MI...
...THERE IS A SLGT RISK OF SVR TSTMS FROM THE UPPER MIDWEST/WESTERN
GREAT LAKES INTO THE SOUTHERN PLAINS...
...SYNOPSIS...
ANOTHER ACTIVE DAY WITH WIDESPREAD SEVERE STORMS IS ANTICIPATED
ACROSS THE UPPER MIDWEST AND OHIO/MIDDLE MISSISSIPPI VALLEYS FRIDAY
AND FRIDAY NIGHT...WITH POTENTIAL FOR DAMAGING WINDS AND
TORNADOES...A FEW OF WHICH COULD BE STRONG.
NEARLY STACKED/NEGATIVELY TILTED UPPER TROUGH WILL LIFT
NORTHEASTWARD OVER THE NORTHERN PLAINS/UPPER MIDWEST ON
FRIDAY...ACCOMPANIED BY A 70-80 KT SOUTHWESTERLY MID LEVEL JET AND A
CONTINUALLY DEEPENING SURFACE LOW /990-985 MB/. IN ASSOCIATION WITH
THIS SURFACE LOW...PRIMARY SYNOPTIC COLD FRONT WILL CONTINUE TO
SHIFT EASTWARD ACROSS THE UPPER MIDWEST/WESTERN GREAT LAKES
REGION...WITH THE SOUTHERN PORTION OF THE FRONT LIKELY RETREATING
WESTWARD ACROSS THE CORN BELT AND CENTRAL/SOUTHERN PLAINS IN
RESPONSE TO ROCKIES LEE SIDE PRESSURE FALLS LATE IN THE PERIOD. A
VERY MOIST/UNSTABLE AIRMASS WILL CONTINUE TO ADVECT NORTHWARD
THROUGH THE CENTRAL STATES AMIDST A STRONG LOW LEVEL JET/MOISTURE
TRANSPORT REGIME.
...UPPER MIDWEST INTO THE OZARKS/SOUTHERN PLAINS...
STRONG/SEVERE STORMS ARE LIKELY TO BE ONGOING AT THE BEGINNING OF
THE PERIOD ACROSS THE MIDWEST/WESTERN GREAT LAKES REGION INCLUDING
PORTIONS OF MN/WI/UPPER MI/IA/MO. DESTABILIZATION/STORM
INTENSIFICATION IS LIKELY ON THE EASTERN/SOUTHERN PERIPHERY OF THIS
ACTIVITY...WITH ADDITIONAL DEVELOPMENT ALONG/AHEAD OF THE COLD FRONT
WITHIN A RATHER MOIST/UNSTABLE AND WEAKLY CAPPED BOUNDARY LAYER.
WITH UPPER 60S/LOWER 70S F DEWPOINTS ALREADY IN PLACE IN MOST
LOCALES...DIURNAL HEATING WILL CONTRIBUTE TO MODERATE/STRONG
INSTABILITY WITH MLCAPES OF 1500-2500 J/KG WITHIN THE PRE-COLD
FRONTAL WARM SECTOR. BENEATH THE STRONG MID/UPPER JET...STRONG LOW
TO MID LEVEL TROPOSPHERIC WIND PROFILES WILL FAVOR BOTH
QUASI-DISCRETE SUPERCELLS/DEVELOPMENT OF BOWING STRUCTURES...WITH
POTENTIAL FOR WIDESPREAD DAMAGING WINDS AND TORNADOES ESPECIALLY IN
THE MODERATE RISK AREA THROUGH FRIDAY EVENING.
THE SOUTH/SOUTHWEST EXTENT OF AN APPRECIABLE SEVERE THREAT WILL BE
MORE CONDITIONAL ACROSS PORTIONS OF THE OZARKS/SOUTHERN
PLAINS...OWING TO RISING UPPER HEIGHTS/LIMITED LARGE SCALE SUPPORT
AND A RETREATING COLD FRONT AND MOIST/UNSTABLE SECTOR. WHILE THE
SEVERE THREAT WILL LIKELY BE MORE CONDITIONAL/RELATIVELY MORE
SCATTERED/ISOLATED IN NATURE...A THREAT FOR LARGE HAIL/DAMAGING
WINDS AND PERHAPS A FEW TORNADOES WILL EXIST.
...PORTIONS OF NY/PA INTO WESTERN NEW ENGLAND...
DIURNAL TSTM DEVELOPMENT APPEARS LIKELY WITHIN LOW-LEVEL WAA
REGIME ACROSS PORTIONS OF NY/PA INTO WESTERN NEW ENGLAND ON FRIDAY.
THE AIRMASS IN WAKE OF WARM FRONTAL PASSAGE IS EXPECTED TO BECOME
MODERATELY UNSTABLE WITH MLCAPES OF 1500-2000 J/KG. OWING TO MODEST
LOW TO MID TROPOSPHERIC FLOW...VERTICAL SHEAR IS NOT FORECAST TO BE
PARTICULARLY STRONG /GENERALLY 30 KT OR LESS/...ALTHOUGH SOME
SUPERCELL STRUCTURES CANNOT BE RULED OUT NEAR THE WARM FRONT IN A
SOMEWHAT HIGHER SRH ENVIRONMENT. OVERALL...THE STRONGEST STORMS WILL
BE CAPABLE OF SEVERE HAIL AND DAMAGING WIND GUSTS FRIDAY
AFTERNOON/EVENING.
...NORTHERN HIGH PLAINS...
A SHORTWAVE TROUGH ROUNDING THE BASE OF UPPER LOW CENTERED OVER
BRITISH COLUMBIA INTO THE PACIFIC NORTHWEST IS FORECAST TO LIFT
NORTHEASTWARD INTO THE NORTHERN HIGH PLAINS THIS PERIOD. A FEW
STRONG TO LOCALLY SEVERE STORMS WITH THE THREAT FOR DAMAGING WINDS
AND SEVERE HAIL WILL BE POSSIBLE GIVEN INCREASINGLY STRONG VERTICAL
SHEAR AND RATHER STEEP LAPSE RATES WITH MUCAPE OF 500-1000 J/KG.
..GUYER.. 06/05/2008
CLICK TO GET WUUS02 PTSDY2 PRODUCT
NOTE: THE NEXT DAY 2 OUTLOOK IS SCHEDULED BY 0800Z
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