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000
FXUS63 KDLH 192048
AFDDLH

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE DULUTH MN
348 PM CDT WED JUN 19 2013

.SHORT TERM...
FAIRLY QUIET WEATHER ACROSS THE REGION THIS AFTERNOON WITH A
TROUGH AXIS DROPPING SOUTHEAST FROM SRN CANADA INTO NORTHERN MN
THIS AFTERNOON. THIS TROUGH AXIS IS SOUTH OF A COLD FRONT THAT IS
DRAPED ACROSS BOTH MANITOBA AND ONTARIO THIS AFTERNOON. FARTHER
WEST IT HAS BEEN THE FOCUS FOR SHOWERS AND THUNDERSTORMS. IN
ADDITION THERE IS A DEVELOPING LOW PRESSURE SYSTEM OVER NORTHERN
WYOMING...WHICH HAS PRODUCED STRONG SOUTHERLY FLOW OVER MUCH OF
THEN PLAINS STATES THIS AFTERNOON. HERE IN NE MN WE ARE ON THE
EASTERN FRINGES OF THAT...AS WELL AS THE SOUTHERN FRINGES OF THE
INFLUENCE OF TROUGH AXIS. THIS HAS PRODUCED AN AREA OF LOCAL WEAK
CONVERGENCE ALONG THE MN/CANADA BORDER...WHERE SOME SHOWERS AND A
FEW THUNDERSTORMS HAVE DEVELOPED. TEMPS HAVE POPPED UP INTO THE
LOW-MID 70S NORTH AND ALONG THE LAKE...TO LOW 80S WEST AND
SOUTHWEST.

TONIGHT THIS TROUGH AXIS WILL CONTINUE TO SHIFT SOUTH TO DRAPE
ACROSS THE CWA BY THE EARLY MORNING HOURS.  EXPECT A NICE LITTLE
AREA OF FRONTOGENESIS TO DEVELOP IN THE VICINITY OF THE BOUNDARY AS
IT CONTINUES TO MOVE INTO THE AREA.  THIS SHOULD PRODUCE AN AREA
WHERE WE SHOULD GET SOME MORE SHOWER AND THUNDERSTORM DEVELOPMENT
DURING THE EVENING AND OVERNIGHT TIME RANGE.  THIS WILL BE MAINLY
CONFINED TO THE NORTHERN PORTIONS OF THE AREA...WITH MORE ISOLATED
ACTIVITY FARTHER SOUTH AWAY FROM THE AREA OF CONVERGENCE.

THURSDAY WE COME INTO THE INFLUENCE OF THE SURFACE LOW OVER WYOMING
AS A NICE SHORTWAVE ROTATES OUT OF THE PLAINS AND RIDES OVER THE
RIDGE AXIS AND ACROSS MN DURING THE AFTERNOON AND EVENING.  DURING
THIS TIME...THE TROUGH AXIS THAT MOVES INTO THE AREA OVERNIGHT WILL
STILL BE DRAPED ACROSS THE NORTHERN CWA...AND SHOULD ACT AS A FOCUS
FOR MORE SHOWER AND THUNDERSTORM ACTIVITY.  EXPECT THAT FOR A LEAST
A SHORT WHILE IN THE MORNING THIS WILL EAST OFF BEFORE THE MAIN WAVE
MOVES INTO THE AREA FROM THE WEST. WITH THE WARM AIR ADVECTION
CONTINUING OVER NIGHT AND THURSDAY WE WILL BE WARM AGAIN THURSDAY
WITH HIGHS IN THE MID AND UPPER 70S.  EXTRA CLOUD COVER WILL KEEP US
OUT OF THE 80S HOWEVER.

.LONG TERM... [THURSDAY NIGHT - TUESDAY]

THERE IS INCREASING CONCERN OF FLASH FLOODING OVER THE COMING DAYS.
THE NORTHLAND WILL BE IN AN WARM AND MOIST ACTIVE WEATHER PATTERN
LATE THIS WEEK AND THROUGH AT LEAST EARLY NEXT WEEK...WHICH COULD
BRING SEVERAL ROUNDS OF THUNDERSTORMS AND HEAVY RAIN. EACH ROUND OF
HEAVY RAIN COULD SIGNIFICANTLY REDUCE THE SOILS ABILITY TO
EFFICIENTLY ABSORB ADDITIONAL RAINFALL AND LEAD TO AN INCREASING
THREAT OF FLASH FLOODING...ESPECIALLY OVER THE WEEKEND AND INTO
EARLY NEXT WEEK. THE MODELS ARE LACKING AGREEMENT TO GET A GOOD IDEA
ON THE LOCATION AND TIMING OF THESE THUNDERSTORMS...BUT MUCH OF THE
NORTHLAND AND SURROUNDING REGION WILL BE UNDER THE GUN...SO TO SPEAK.

THE FIRST ROUND OF THUNDERSTORMS WILL LIKELY COME THURSDAY NIGHT
AND/OR FRIDAY MORNING. IT APPEARS A COMPLEX OF THUNDERSTORMS COULD
DEVELOP IN THE LOW PRESSURE AND WARM/MOIST SOUTHERLY FLOW IN THE
NORTHERN PLAINS THURSDAY AFTERNOON...AND THIS COMPLEX COULD SPREAD
THROUGH THE NORTHLAND THURSDAY NIGHT AND FRIDAY MORNING. HIGH
MOISTURE TRANSPORT OVER THE NORTHLAND...INCREASING PRECIPITABLE
WATER VALUES INCREASING TO 1.5 TO 2 INCHES...DEEP LAYER (0-6 KM)
BULK SHEAR OF MORE THAN 30 KNOTS...A LOW LEVEL JET OF 30 TO 40
KNOTS...AND MOST UNSTABLE CAPE OF 500 TO 1500 J/KG COULD RESULT IN
SEVERE WEATHER. LARGE HAIL...DAMAGING WINDS...AND HEAVY RAIN ARE
CERTAINLY POSSIBLE.

THERE COULD BE A BIT OF LULL IN SHOWER/STORM ACTIVITY FRIDAY
AFTERNOON BEFORE ANOTHER ROUND POTENTIALLY COMES LATE FRIDAY
AFTERNOON INTO FRIDAY NIGHT. A WARM FRONT MAY SET UP ALONG OR JUST
SOUTH OF THE SOUTHERN FORECAST AREA FRIDAY AND RESULT IN MORE
THUNDERSTORMS NEAR THE FRONT. THESE STORMS COULD ALSO BE
SEVERE...AND WITH HIGH PRECIPITABLE WATER VALUES OF 1.5 TO 2
INCHES...HEAVY RAIN IS POSSIBLE.

THE WARM FRONT COULD LINGER ACROSS THE SOUTHERN FORECAST AREA OR
ATTEMPT TO LIFT THROUGH THE NORTHLAND SATURDAY AND SUNDAY. THERE ARE
CONSIDERABLE DIFFERENCES IN THE MODELS AND CONFIDENCE IS NOT AS
GREAT. HOWEVER...THE NORTHLAND COULD GET ONE OR MORE ROUNDS OF
THUNDERSTORMS SATURDAY AND SATURDAY NIGHT...INCLUDING MORE SEVERE
WEATHER AND HEAVY RAIN. THE GFS EVEN KEEPS THE NORTHLAND UNDER THE
GUN FOR THUNDERSTORMS AND HEAVY RAIN THROUGH THE FIRST HALF OF NEXT
WEEK...BUT THE ECMWF SUGGEST MAYBE A BREAK WITH WEAK HIGH PRESSURE.

WE WILL NEED TO KEEP A CLOSE EYE ON THIS PATTERN OVER THE COMING
DAYS AND MAY NEED TO CONSIDER A FLASH FLOOD WATCH. THERE COULD BE
SIGNIFICANT CHANGES IN THE MODELS AFTER EACH ROUND OF THUNDERSTORMS
DUE TO ITS EFFECTS ON THE OVERALL PATTERN. IT WORTH NOTING THAT
PARTS OF THE NORTHLAND...INCLUDING THE TWIN PORTS...WAS FACED WITH
SEVERE FLASH FLOODING ONLY 1 YEAR AGO DUE TO MULTIPLE ROUNDS OF
HEAVY RAIN AND THUNDERSTORMS.

&&

.AVIATION...18Z TAF ISSUANCE...
THERE ARE ONLY FEW/SCT LOW AND/OR HIGH CLOUDS ACROSS NE MINNESOTA
AND NW WISCONSIN EARLY THIS AFTERNOON. WHILE VFR CONDITIONS WILL
LIKELY CONTINUE THROUGH TOMORROW MORNING...MUCH OF THE REGION HAS
A LOW THREAT OF SHOWERS AND THUNDERSTORMS LATER THIS AFTERNOON AND
THROUGH TOMORROW MORNING. EXPECT INCREASING LOW LEVEL CUMULUS
DEVELOPING THROUGH THE AFTERNOON. ANY SHOWERS AND STORMS COULD
BRING BRIEF MVFR CIGS AND VSBYS TO THE REGION...AND WE WILL NEED
TO MONITOR FOR DEVELOPMENT BEFORE ADDING MUCH MVFR TO THE
FORECASTS. ALSO...THERE IS A LOW THREAT OF BRIEF FOG LATE TONIGHT
AND TOMORROW MORNING...BUT CONFIDENCE AT THIS POINT IS TO
INTRODUCE IT.


&&

.POINT TEMPS/POPS...
DLH  56  76  56  75 /  30  70  70  50
INL  54  80  60  78 /  50  60  70  40
BRD  62  79  65  82 /  30  70  70  30
HYR  58  79  64  84 /  30  60  70  60
ASX  56  78  57  77 /  40  60  70  60

&&

.DLH WATCHES/WARNINGS/ADVISORIES...
MN...NONE.
WI...NONE.
LS...NONE.
&&

$$

SHORT TERM...LE
LONG TERM....GROCHOCINSKI
AVIATION...GROCHOCINSKI