Severe Thunderstorm Warning 165, NWS Twin Cities, MN

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE TWIN CITIES/CHANHASSEN MN
259 AM CDT WED AUG 23 2006

.DISCUSSION...TODAY THROUGH FRIDAY NIGHT

A CONVECTIVE SYSTEM CONTINUES TO PUSH ACROSS CENTRAL MINNESOTA
EARLY THIS MORNING...IN RESPONSE TO STRONG LOW LEVEL WARM AIR
ADVECTION. THIS ACTIVITY WILL GRADUALLY SLIDE EAST AND SLIGHTLY
SOUTH ACROSS THE FORECAST AREA THROUGH MID MORNING. THE RESULTANT
AIRMASS WILL BE FAIRLY STABILIZED ACROSS THE WESTERN CWA THIS
AFTERNOON...ALTHOUGH THUNDERSTORM REDEVELOPMENT IS POSSIBLE ACROSS
THE EASTERN HALF ALONG THE NORTHEASTERN EDGE OF THE CAP. WHILE
LARGE SCALE FORCING WILL BE LACKING...LOW LEVEL CONVERGENCE ALONG
THE FRONT COMBINED WITH DIURNAL HEATING MAY BE SUFFICIENT FOR
CONVECTIVE DEVELOPMENT. HAVE THEREFORE RETAINED CHANCE POPS ACROSS
THE EASTERN HALF OF THE FORECAST AREA FOR THIS AFTERNOON. IF
THUNDERSTORM INITIATION OCCURS...THUNDERSTORMS THAT DEVELOP WILL
HAVE THE POTENTIAL TO BECOME SEVERE...GIVEN GFS/NAM PROGGED 0-6KM
BULK SHEAR VALUES IN EXCESS OF 40 KNOTS.

A FRONTAL BOUNDARY WILL LINGER ACROSS SOUTHERN MINNESOTA ON
THURSDAY NIGHT...CONTRIBUTING TO THE POTENTIAL FOR ANOTHER ROUND
OF NOCTURNAL THUNDERSTORM DEVELOPMENT. HAVE RETAINED 30-40 POPS
ACROSS THE SOUTHERN HALF OF THE CWA.

THE SURFACE TROUGH ASSOCIATED WITH A DECENT SHORTWAVE TRACKING
ACROSS SOUTHERN SASKATCHEWAN/MANITOBA WILL REACH WESTERN MINNESOTA
LATE THURSDAY AFTERNOON. STRONG SYNOPTIC FEATURES /TRIPLE POINT
ACROSS THE EASTERN DAKOTAS/ AND DECENT INSTABILITY PARAMETERS
INDICATE SUPERCELL DEVELOPMENT IS LIKELY...WITH A POTENTIAL FOR
TORNADOGENESIS ACROSS SOUTHERN MINNESOTA. WARM AIR ADVECTION AND
RESULTANT THUNDERSTORM ACTIVITY WILL SPREAD ACROSS CENTRAL
MINNESOTA AND WEST CENTRAL WISCONSIN THURSDAY NIGHT INTO FRIDAY.
HAVE INCREASED POPS TO 50 PERCENT CWA-WIDE.

THUNDERSTORM ACTIVITY SHOULD TEMPORARILY WIND DOWN ON FRIDAY AS THE
LOW SHIFTS EASTWARD TO THE GREAT LAKES...BUT HAVE RETAINED A
SLIGHT CHANCE OF THUNDERSTORMS ACROSS THE SOUTHEAST IN RESPONSE TO
A SYSTEM FORECAST TO LIFT FROM THE CENTRAL PLAINS TO THE MID
MISSISSIPPI RIVER VALLEY.

ONLY MINOR TWEAKS WERE MADE TO TEMPERATURES DURING THE SHORT TERM
PERIOD...WITH PREVAILING NEAR TO SLIGHTLY ABOVE NORMAL VALUES
ANTICIPATED.

LONGER TERM...SATURDAY THROUGH THURSDAY
SATURDAY FORECAST STILL FULL OF UNCERTAINTY. LARGE UPPER TROF STILL
INFLUENCING THE WEATHER OVER THE AREA WITH UPPER JET POSITIONED
ACROSS NORTH CENTRAL MN NORTHEASTWARD TOWARDS THE EASTERN LK
SUPERIOR SHORE. SFC LOW MOVING ACROSS THE MID MISSISSIPPI RIVER
VALLEY NOW PRESENT ON GFS AND ECMWF SOLUTIONS. FORCING SUGGESTED BY
THIS PATTERN /RIGHT ENTRANCE OF UPPER JET...H5 TROF AXIS SWINGING
ACROSS...AND DEFORMATION TYPE FORCING ON NORTHWEST FLANK OF SFC LOW
TRACK/ YIELDS POTENTIAL FOR PRECIPITATION. SOUTHERN MN AND AND
PORTION OF WI COUNTIES WOULD BE MOST LIKELY AREAS TO BE
AFFECTED BY PRECIPITATION SATURDAY. THIS HIGHLY DEPENDENT ON
DEVELOPMENT AND TRACK OF LOW. HAVE TWEAKED POP GRIDS TO REFLECT THIS
POTENTIAL BUT KEPT IN SLIGHT CATEGORY. AS THE WEEKEND PROGRESSES
HIGH PRESSURE BUILDS IN AS UPPER LEVEL FLOW BECOMES MORE AMPLIFIED
WITH RIDGE BUILDING IN ACROSS THE NORTHERN PLAINS TOWARDS THE END OF
THE PERIOD.

&&

.MPX WATCHES/WARNINGS/ADVISORIES...
MN...NONE.
WI...NONE.
&&

LS/MDB

HAZARDOUS WEATHER OUTLOOK
NATIONAL WEATHER SERVICE TWIN CITIES/CHANHASSEN MN
532 AM CDT TUE AUG 22 2006

MNZ041>045-047>070-073>078-082>085-091>093-WIZ014>016-023>028-
231100-
DOUGLAS-TODD-MORRISON-MILLE LACS-KANABEC-STEVENS-POPE-STEARNS-
BENTON-SHERBURNE-ISANTI-CHISAGO-LAC QUI PARLE-SWIFT-CHIPPEWA-
KANDIYOHI-MEEKER-WRIGHT-HENNEPIN-ANOKA-RAMSEY-WASHINGTON-
YELLOW MEDICINE-RENVILLE-MCLEOD-SIBLEY-CARVER-SCOTT-DAKOTA-
REDWOOD-BROWN-NICOLLET-LE SUEUR-RICE-GOODHUE-WATONWAN-BLUE EARTH-
WASECA-STEELE-MARTIN-FARIBAULT-FREEBORN-POLK-BARRON-RUSK-
ST. CROIX-PIERCE-DUNN-PEPIN-EAU CLAIRE-
532 AM CDT TUE AUG 22 2006

THIS HAZARDOUS WEATHER OUTLOOK IS FOR PORTIONS OF CENTRAL AND
SOUTH CENTRAL MINNESOTA...AND WEST CENTRAL WISCONSIN.

.DAY ONE...TODAY AND TONIGHT

SHOWERS AND THUNDERSTORMS ARE EXPECTED TO DEVELOP AS A WARM FRONT
LIFTS NORTH ACROSS CENTRAL MINNESOTA AND WEST CENTRAL WISCONSIN
TONIGHT INTO WEDNESDAY. A FEW OF THESE THUNDERSTORMS MAY BECOME
STRONG ENOUGH TO PRODUCE LARGE HAIL...MAINLY WEST OF THE
INTERSTATE 35 CORRIDOR FROM MORA TO LAKEVILLE.

.DAYS TWO THROUGH SEVEN...WEDNESDAY THROUGH MONDAY

NOCTURNAL SHOWER AND THUNDERSTORM ACTIVITY FROM TUESDAY NIGHT IS
EXPECTED TO BECOME ORGANIZED INTO A THUNDERSTORM COMPLEX...AND
MOVE ACROSS CENTRAL MINNESOTA AND WEST CENTRAL WISCONSIN ON
WEDNESDAY. THERE IS A SLIGHT RISK OF LARGE HAIL AND DAMAGING WINDS
WITH THIS ACTIVITY ON WEDNESDAY.

THE WEATHER PATTERN WILL REMAIN UNSETTLED THROUGH FRIDAY. MONITOR
FUTURE OUTLOOKS FOR ADDITIONAL DETAILS ON SEVERE WEATHER
POTENTIAL.

.SPOTTER INFORMATION STATEMENT...

SKYWARN SPOTTER ACTIVATION MAY BE NEEDED THIS EVENING AND TONIGHT
ACROSS WEST CENTRAL AND CENTRAL MINNESOTA.

SPECIAL WEATHER STATEMENT
NATIONAL WEATHER SERVICE TWIN CITIES/CHANHASSEN MN
131 AM CDT WED AUG 23 2006

MNZ042-043-048-049-230730-
MORRISON-POPE-STEARNS-TODD-
131 AM CDT WED AUG 23 2006

...SIGNIFICANT WEATHER ALERT FOR TODD...MORRISON...STEARNS AND POPE
COUNTIES UNTIL 230 AM CDT...

AT 124 AM CDT...NATIONAL WEATHER SERVICE DOPPLER RADAR WAS TRACKING
STRONG THUNDERSTORMS ALONG A LINE EXTENDING FROM 5 MILES NORTHEAST OF
LONG PRAIRIE TO 10 MILES NORTHWEST OF SAUK CENTRE TO 12 MILES
SOUTHWEST OF GLENWOOD...AND MOVING SOUTHEAST AT 55 MPH.

WINDS AROUND 50 MPH ARE EXPECTED WITH THESE STORMS.

THESE STORMS WILL BE...
  NEAR LITTLE FALLS BY 145 AM.
  NEAR ALBANY BY 155 AM.
  NEAR PAYNESVILLE BY 205 AM.

PRELIMINARY LOCAL STORM REPORT
NATIONAL WEATHER SERVICE TWIN CITIES/CHANHASSEN MN
322 AM CDT WED AUG 23 2006

..TIME...   ...EVENT...      ...CITY LOCATION...     ...LAT.LON...
..DATE...   ....MAG....      ..COUNTY LOCATION..ST.. ...SOURCE....
            ..REMARKS..

0320 AM     TSTM WND DMG     CAMBRIDGE               45.56N 93.23W
08/23/2006                   ISANTI             MN   LAW ENFORCEMENT

            TREE BLOWN DOWN.

&&

RAH