Lightning Strike in Minnesota, June 19, 2002

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE DULUTH MN
255 PM CDT TUE JUN 18 2002

FORECAST FOCUS IS ON THUNDERSTORM DEVELOPMENT...AND HEAVY RAIN
POTENTIAL.

MODELS IN DECENT AGREEMENT. MODEL QPF IS ALSO IN THE BALLPARK
AMONGST EACH OTHER TONIGHT. HAVE FOLLOWED THE ETA FOR MOST OF
DETAILS...BUT IT IS TOO HIGH ON PRECIP WATER AND A BIT HIGH ON
SURFACE DEWPOINTS.

VORT MAX...DIVERGENCE AHEAD OF JET AND THETA-E ADVECTION CAUSING
THUNDERSTORMS TO BREAK OUT ACROSS FAR WESTERN ZONES THIS AFTERNOON.
850MB THETA-E RIDGE TO NOSE INTO CWA TONIGHT...WITH 40-45KT FLOW BY
06Z WED. SHORTWAVE AND CONTINUED THETA-E ADVECTION TO BRING
THUNDERSTORMS TO REST OF CWA OVERNIGHT. PRECIP WATER VALUES AT 12Z AT
DDC/OAX/TOP WERE AROUND 1.25 INCHES AND MODELS FORECAST 1.5-1.75 BY
00Z THU OVER CWA. WILL KEEP HEAVY RAIN WORDING IN ZONES...BUT WITH
FLASH FLOOD GUIDANCE HIGH WILL NOT ISSUE ANY HEADLINE ATTM. I WILL
KEEP THE HEAVY RAIN WORDING THOUGH...AS HIGH MOISTURE CONTENT AND
CORFIDI VECTORS DECREASING TO 15 KT OR LESS TONIGHT SUPPORT IT. A
FEW CELLS THIS AFTERNOON HAVE PRODUCED SMALL HAIL. LIFTED INDEX AT
SURFACE AND 850MB DROPS FURTHER THIS AFTERNOON AND EVENING...BUT
FREEZING LEVELS ON THE RISE AND 0-6KM SHEAR DECREASE...AND THAT
SHOULD LIMIT SEVERE THREAT. SEE SWOMCD 1159 FOR FURTHER DETAILS.

FRONT AND THETA-E RIDGE WILL KEEP THUNDERSTORMS IN THE FORECAST INTO
THURSDAY MORNING...BUT CHANCES WILL BE DECREASING WEDNESDAY NIGHT.
CWA IS UNDER THE THETA-E RIDGE WEDNESDAY AND 500MB WINDS INCREASE
TO 50-65 KNOTS BY WEDNESDAY AFTERNOON...WITH THE 850MB FLOW 40-50
KNOTS. 0-6KM SHEAR 50-55 KNOTS BY 00Z THU...SO POTENTIAL FOR SEVERE
EXISTS AND NEW SWODY2 PUTS ALL OF CWA IN SLIGHT RISK. ONE OF THE
LIMITING FACTORS WILL BE AMOUNT OF INSTABILITY REALIZED IN THE
AFTERNOON DUE TO CLOUDS FROM OVERNIGHT CONVECTION. THE CLOUDS WILL
ALSO HAVE A BIG IMPACT ON HIGHS. WILL EXPECT SOME CLEARING...AND GO
WITH PREVIOUS ZONE PACKAGE...ABOVE GUIDANCE HIGHS.

COORD WITH FGF AND MPX.

.DLH...NONE.

MELDE