Severe Thunderstorm Warning 4, NWS Duluth, MN

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE DULUTH MN
315 PM CDT SAT APR 17 2004

.DISCUSSION...MAIN FOCUS IS ON SEVERE WEATHER POTENTIAL SUNDAY.

THE MODELS ARE INDICATING WHAT MIGHT BE A MAJOR SEVERE WEATHER
OUTBREAK ACROSS PORTIONS OF OUR CWA SUNDAY AND SUNDAY EVENING.
THE 12Z MODELS ARE FAIRLY SIMILAR IN THEIR HANDLING OF THE SURFACE
LOW EXPECTED TO MOVE INTO CENTRAL MINNESOTA BY SUNDAY EVENING.
WILL SIDE WITH ETA FOR THE DETAILS...GIVEN SOME POTENTIAL
CONVECTIVE FEEDBACK WITH THE GFS ON SUNDAY.

THE SYSTEM SHOULD HOLD OFF SOMEWHAT ON THE DEVELOPMENT OF
PRECIPITATION TONIGHT. THE LOW WILL NOT REALLY ADVANCE INTO THE
PLAINS STATES UNTIL AFTER MIDNIGHT...AND THE BEST OVERRUNNING
DOES NOT ARRIVE UNTIL LATER TONIGHT OR BETTER YET ON SUNDAY.
SHOULD BE SOME SCATTERED SHOWERS THIS EVENING...WITH THUNDERSTORMS
POSSIBLE AFTER MIDNIGHT AS H8 LI VALUES DROP TO BELOW ZERO.

STRONG OVERRUNNING WILL TAKE PLACE ON SUNDAY...BRINGING A SOAKING
RAIN TO MUCH OF THE CWA. THE LOW IS FORECAST TO MOVE INTO CENTRAL
MINNESOTA DURING THE LATE AFTERNOON...ALLOWING THE WARM FRONT
TO LIFT INTO NORTHWESTERN WISCONSIN. THE AIR SOUTH OF THE FRONT WILL
BE VERY UNSTABLE...AND ALL FORECAST PARAMETERS INDICATE THE
POTENTIAL FOR A FEW TORNADIC SUPERCELLS IN EC MN/NW WI DURING THE
LATE AFTERNOON AND EARLY EVENING. THE 0-2KM VGP IS FORECAST TO BE
AROUND 0.5...SWEAT IS FORECAST TO BE AROUND 500 AND THE 0-1KM SR
HELICITY IS FORECAST TO BE OVER 400 M2/S2 WITH A STRONGLY VEERING
HODOGRAPH PROFILE. STRONG CONVERGENCE AND OVERRUNNING ALSO EXPECTED
IN THE VICINITY OF THE FRONT. COOL NORTHEAST WINDS NORTH OF THE
FRONT WILL MEAN LOW LCLS JUST ALONG AND NORTH OF THE FRONT...
WHICH WILL FURTHER INCREASE THE POTENTIAL FOR ROTATING STORMS. WILL
ADD THE MENTION OF SEVERE STORMS TO THE SOUTHERN ZONES. NORTHERN
PORTIONS OF THE CWA COULD RECEIVE A SUBSTANTIAL AMOUNT OF PCPN
AS WELL...WITH STRONG OVERRUNNING AND PW AROUND 1.25 INCHES.

THE PRECIPITATION WILL CONTINUE INTO THE NIGHT SUNDAY NIGHT...
WITH STORMS CONTINUING INTO THE EVENING ACROSS AT LEAST THE
SOUTHEAST HALF OF THE CWA. THE PRECIPITATION SHOULD DIMINISH ON
MONDAY...LEAVING PARTLY SUNNY SKIES FOR TUESDAY. NO OTHER MAJOR
SYSTEMS ARE EXPECTED FOR THE DURATION OF THE EXTENDED.

TEMPS WILL BE MUCH COOLER NEAR LAKE SUPERIOR...AS LOW CLOUDS
DEVELOP AND WINDS STRENGTHEN. COULD ALSO BE SOME FOG AND DRIZZLE
AT TIMES AFTER THE RAIN INITIALLY MOVES IN. WILL STAY ON THE COOL
SIDE OF MOS DUE TO CLOUDS/PCPN EXPECTED FOR MOST AREAS. THE
ONLY EXCEPTION IS OUR SOUTHERN ZONES WHICH SHOULD SEE WARMER
TEMPS IN THE VICINITY OF THE WARM FRONT.

&&

.DLH...WATCHES/WARNINGS/ADVISORIES

MN...NONE.
WI...NONE.

DAP

HAZARDOUS WEATHER OUTLOOK...UPDATED
NATIONAL WEATHER SERVICE DULUTH MN
839 AM CDT SAT APR 17 2004

MNZ010>012-018>021-025-026-033>038-WIZ001>004-006>009-181230-
ASHLAND-BAYFIELD-BURNETT-C. ST. LOUIS-CROW WING-DOUGLAS-IRON-
KOOCHICHING-N. AITKIN-N. CASS-N. ITASCA-N. LAKE/N. COOK-N. ST. LOUIS-
PINE-PRICE-S. AITKIN-S. CASS-S. COOK/LAKESHORE-S. ITASCA-
S. LAKE/LAKESHORE-S. ST. LOUIS/CARLTON-SAWYER-WASHBURN-
839 AM CDT SAT APR 17 2004

...SLIGHT RISK OF SEVERE THUNDERSTORMS TONIGHT AND TOMORROW...

THIS HAZARDOUS WEATHER OUTLOOK IS FOR NORTHEASTERN MINNESOTA AND
NORTHWESTERN WISCONSIN.

.DAY ONE...TODAY AND TONIGHT

ISOLATED THUNDERSTORMS ARE EXPECTED LATE TONIGHT ACROSS
NORTHWEST WISCONSIN AND THERE IS A SLIGHT CHANCE THAT SOME MAY BE
SEVERE WITH HAIL GREATER THAN 3/4 INCH OR GUSTY WINDS GREATER
THAN 58 MPH...ESPECIALLY OVER PRICE COUNTY AND SOUTHERN PORTIONS OF
BURNETT...WASHBURN...AND SAWYER COUNTIES. NORTHEAST WINDS WILL
INCREASE LATE TONIGHT ON LAKE SUPERIOR. A SMALL CRAFT ADVISORY MAY
BE NEEDED ALONG THE NEARSHORE AREAS OF LAKE SUPERIOR.

.DAYS TWO THROUGH SEVEN...SUNDAY THROUGH FRIDAY.

THERE IS A SLIGHT CHANCE OF SEVERE THUNDERSTORMS SUNDAY AND SUNDAY
NIGHT. THE BEST CHANCE OF SEVERE WEATHER IS SOUTH OF LINE FROM
GRAND MARAIS...THROUGH THE IRON RANGE...TO BRAINERD...AND ACROSS ALL
OF NORTHWEST WISCONSIN. THE GREATEST THREAT WITH THESE SEVERE
STORMS IS LARGE HAIL AND DAMAGING WINDS...HOWEVER ISOLATED TORNADOES
MAY DEVELOP ACROSS NORTHWEST WISCONSIN. BRISK NORTHEAST WINDS WILL
OCCUR OVER LAKE SUPERIOR SUNDAY AND SUNDAY NIGHT. A SMALL CRAFT
ADVISORY MAY BE NEEDED ALONG THE NEARSHORE AREAS OF LAKE SUPERIOR.

.SPOTTER INFORMATION STATEMENT...

SKYWARN SPOTTER ACTIVATION MAY BE NEEDED LATE TONIGHT AND
TOMORROW.

&&

MORE INFORMATION MAY BE OBTAINED AT THE FOLLOWING URL:

HTTP://WWW.CRH.NOAA.GOV/DLH

LJT