Area Forecast Discussion
Issued by NWS Duluth, MN

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FXUS63 KDLH 281836
AFDDLH

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE DULUTH MN
136 PM CDT TUE JUL 28 2015

.UPDATE...
ISSUED AT 136 PM CDT TUE JUL 28 2015

REMOVED THE MENTION OF RAIN FOR THE REST OF THE AFTERNOON AS NOTED
BY RADAR. REST OF THE FORECAST UNCHANGED.

UPDATE ISSUED AT 1146 AM CDT TUE JUL 28 2015

SHOWERS CONTINUE TO WIND DOWN WITH SOME NEAR THE CANADIAN BORDER
AND OVER THE EASTERN EDGE OF THE WI FORECAST AREA. THIS ACTIVITY
WILL BE OUT OF THE AREA BY 1 PM. LATEST HIRES MODELS CONTINUE TO
INDICATE ALMOST NO ADDITIONAL DEVELOPMENT THIS AFTERNOON...BUT
WITH THE FRONT NOW INTO NW MN...WILL MONITOR FOR ADDITIONAL
DEVELOPMENT. REST OF THE FORECAST IN THE BALLPARK.

UPDATE ISSUED AT 939 AM CDT TUE JUL 28 2015

SCATTERED SHOWERS AND AN ISOLD STORM IN NW WI WILL DIMINISH
THROUGH THE REST OF THE MORNING. THE COLD FRONT REMAINS WELL TO
THE WEST OF THE FORECAST AREA AND IS JUST ENTERING THE RED RIVER
VALLEY OF THE NORTH AT 1430Z. THE PROGNOSIS FOR ADDITIONAL SHOWER
AND STORM ACTIVITY THIS AFTERNOON HAS DIMINISHED GREATLY PER THE
LATEST HRRR/RAP RUNS. HAVE REDUCED POPS/QPF CONSIDERABLY FOR THIS
AFTERNOON. HOWEVER...THE WARM AND HUMID CONDITIONS WILL PREVAIL
UNTIL THE FRONT ARRIVES. ADJUSTED FOR THESE TRENDS.

&&

.SHORT TERM...(TODAY THROUGH WEDNESDAY)
ISSUED AT 443 AM CDT TUE JUL 28 2015

A COMPLEX FORECAST IN THE SHORT TERM AS TWO ROUNDS OF SHOWERS AND
STORMS ARE EXPECTED TO MOVE ACROSS THE REGION TODAY...THEN BECOMING
VERY WINDY TOMORROW BEHIND A STRONG COLD FRONT.

AN AREA OF LOW PRESSURE CURRENTLY ALONG THE NORTH DAKOTA/CANADA
BORDER THIS MORNING WILL PROGRESS NORTHEASTWARD TODAY WITH A
SECONDARY LOW ALONG THE CENTRAL ND/SD BORDER THIS MORNING
PROGRESSING IN A SIMILAR FASHION TOWARDS NORTHEAST MINNESOTA
TONIGHT. FROM THIS SECONDARY LOW PRESSURE EXTENDS A WARM FRONT WHICH
BY 18Z WILL BE LIFTING NORTHEAST TOWARDS THE BRAINERD LAKES REGION.
AHEAD OF THIS WARM FRONT AN MCS WAS PROGRESSING EASTWARD OUT OF THE
DAKOTAS INTO WEST-CENTRAL TO SOUTHWEST MINNESOTA.

FOCUS FOR THIS MORNING WILL BE THE CONVECTION MOVING IN FROM THE
WEST AHEAD OF THE WARM FRONT...WITH THE QUESTION OF JUST HOW WELL
THESE STORMS HOLD UP AS THEY REACH THE NORTHLAND. SHORT-RANGE
GUIDANCE AND MESOANLYSIS INDICATE APPRECIABLE ELEVATED INSTABILITY
IS IN PLACE AS OF 09Z THIS MORNING ACROSS NORTH-CENTRAL MINNESOTA
WITH 500-1000 J/KG MUCAPE. SHOULD STORMS SUSTAIN...WHICH PER LATEST
RADAR/LIGHTNING THEY DO NOT SHOW SIGNS OF WEAKENING YET...WIDESPREAD
STRONG THUNDERSTORMS PRODUCING INTENSE RAINFALL WILL OVERSPREAD MUCH
OF NORTHEAST MINNESOTA THIS MORNING. THIS FIRST ROUND OF STORMS WILL
BE IN A VERY MOIST ENVIRONMENT WITH PWATS APPROACHING 2.0 INCHES
ACROSS THE REGION...WHICH IS IN THE 99TH PERCENTILE COMPARED TO
CLIMO FOR PARTS OF THE REGION. THINK THE QPF OUTPUT FROM MUCH OF THE
GUIDANCE IS A BIT UNDERDONE GIVEN THE POTENTIAL FOR DOWNPOURS. STORM
MOTIONS SHOULD BE SWIFT ENOUGH TO LIMIT FLOODING RISK...BUT
LOCALIZED FLOODING IS ALWAYS POSSIBLE WITH THIS TYPE OF ENVIRONMENT.

EARLY THIS AFTERNOON THIS CONVECTION IS EXPECTED TO RUN OUT OF STEAM
AS IT PROGRESSES INTO NORTHWEST WISCONSIN AND THE MINNESOTA
ARROWHEAD AS IT MOVES AHEAD OF THE BEST ELEVATED INSTABILITY. STILL
HAVE SOME CONCERNS WITH THIS...BUT THINK AS SOON AS IT CROSS THE
STATE LINE WE WILL SEE A RAPID DECREASE IN INTENSITY AS STORMS
WEAKEN. ACROSS THE REST OF THE REGION THE MORNING CONVECTION WILL
DIMINISH...THOUGH THE HOT AND HUMID CONDITIONS WILL MAKE FOR A MUGGY
AFTERNOON. CLOUDS ARE EXPECTED TO LINGER THROUGH THE DAY...THOUGH
ANY CLEARING THIS AFTERNOON ACROSS NORTH CENTRAL/NORTHEAST MINNESOTA
WILL INCREASE THE THREAT FOR SEVERE WEATHER THIS AFTERNOON.

THIS AFTERNOON...THE NORTH-SOUTH ORIENTED COLD FRONT WILL PROGRESS
EASTWARD ACROSS NORTHERN MINNESOTA. WHILE ISOLATED CONVECTION WILL
BE POSSIBLE ALONG THE FRONT...THERE WILL BE A STRONG CAP IN PLACE
DUE TO THE VERY WARM AIRMASS AHEAD OF THE FRONT. HOWEVER...STORMS
THAT DO BREAK THE CAP WILL RAPIDLY GROW DUE TO EXTREME
INSTABILITY...MLCAPE VALUES 2000-400 J/KG PER A BLEND OF SHORT-RANGE
GUIDANCE. WIND PROFILES ARE NOT ESPECIALLY SUPPORTIVE OF SUPERCELL
THUNDERSTORMS WITH ONLY 20-30KTS EFFECTIVE BULK SHEAR AND WEAK WINDS
AROUND 3-5KM PRODUCING A LESS-THAN-STELLAR HODOGRAPH. SHOULD STORMS
DEVELOP THINK THEY COULD QUICKLY BE CAPABLE OF PRODUCING LARGE
HAIL...BUT NOT FOR LONG GIVEN THE WIND PROFILES...WITH GUSTY WINDS
POSSIBLE AS STORMS COLLAPSE. THIS THREAT WILL NEED TO BE RE-
EVALUATED DEPENDING ON HOW STORMS PROGRESS THIS MORNING...BUT AT
THIS TIME THINK THERE IS A CONDITIONAL RISK FOR SEVERE THUNDERSTORMS
AS THE FRONT MOVES EAST ACROSS NORTHEAST MINNESOTA LATE THIS
AFTERNOON.

TONIGHT...FRONT WILL CLEAR THROUGH THE CWA BY THE EVENING HOURS WITH
A FEW ISOLATED SHOWERS/STORMS POSSIBLE ACROSS THE ARROWHEAD AND
NORTHWEST WISCONSIN AHEAD OF IT...WITH SKIES CLEARING BEHIND THE
FRONT. COLD AIR MOVING IN ALOFT SHOULD RESULT IN SOME LOWS REACHING
THE UPPER 50S IN NORTHEAST MINNESOTA...THOUGH WINDS ARE EXPECTED TO
BE 5 TO 10 MPH OUT OF THE SOUTHWEST THROUGHOUT THE NIGHT.

WEDNESDAY...WINDY WITH A CHANCE FOR SHOWERS ALONG THE INTERNATIONAL
BORDER. AS THE MAIN SFC LOW PROGRESS NORTHWARD THROUGH WESTERN
ONTARIO EXPECT SOME WRAP AROUND SHOWERS TO EFFECT THE INTERNATIONAL
BORDER REGION...BUT OTHERWISE MOSTLY TO PARTLY SUNNY ACROSS THE REST
OF THE REGION. WINDS WILL BE THE MAIN CONCERN...DEEP MIXING TO
AROUND 750MB WILL RESULT IN GUSTS TO 35-45 MPH BEING MIXED DOWN TO
THE SURFACE. HIGHS WILL BE CLOSE TO SEASONABLE IN THE MID 70S TO
NEAR 80...AND DOWN TO THE LOW 70S ACROSS THE INTERNATIONAL BORDER
INTO THE TIP OF THE MINNESOTA ARROWHEAD REGION.

.LONG TERM...(WEDNESDAY NIGHT THROUGH MONDAY)
ISSUED AT 443 AM CDT TUE JUL 28 2015

THE EXTENDED PERIOD WILL FEATURE A PACIFIC... ALMOST ZONAL FLOW
EARLY...THEN AS THE WESTERN RIDGE BUILDS EXPECT A MORE NORTHWESTERLY
FLOW. ALL THE WHILE A CLOSED UPPER LOW WILL BECOME SEMI-PERMANENT
OVER ONTARIO. IT IS THIS UPPER LOW THAT WILL PUSH EMBEDDED S/WVS
THROUGH THE REGION LATER IN THE WEEK. THE MN ARROWHEAD WILL HAVE A
CHANCE OF SOME SHOWERS THURSDAY NIGHT...BUT THE CHANCES OF MORE
WIDESPREAD SHOWERS AND THUNDERSTORMS WILL COME LATE IN THE WEEKEND
AND EARLY NEXT WEEK AS A STRONGER WAVE ROTATES ACROSS THE WESTERN
GREAT LAKES.

&&

.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z WEDNESDAY AFTERNOON)
ISSUED AT 1252 PM CDT TUE JUL 28 2015

MUCH OF NE MINNESOTA AND NW WISCONSIN HAD GUSTY SOUTHERLY WINDS
AND POCKETS OF LINGERING MVFR CEILINGS. OTHERWISE...BKN/OVC HIGH
CLOUD COVER COVERED THE REGION.

SHOWERS AND THUNDERSTORMS ARE POSSIBLE LATER THIS AFTERNOON AND
EARLY THIS EVENING. AN APPROACHING COLD FRONT FROM THE WEST WILL
POOL MOISTURE AHEAD OF THE FRONT...POSSIBLY ENOUGH TO DEVELOP SOME
THUNDER. THERE COULD BE BRIEF PERIODS OF MVFR CEILINGS/VISIBILITY
WITH THE PASSAGE OF THE SHOWERS AND STORMS. THE REGION SHOULD
QUICKLY CLEAR...GENERALLY FROM WEST TO EAST...IN THE WAKE OF THE
FRONT WHEN IT PASSES THROUGH THE REGION LATE THIS AFTERNOON AND
THIS EVENING.

GUSTY SW WINDS ARE LIKELY THROUGH LATE THIS EVENING. HOWEVER...THE
WINDS MAY WEAKEN LATER TONIGHT WHEN THE BOUNDARY LAYER DECOUPLES
WITH THE NOCTURNAL COOLING. THIS SITUATION MIGHT SET UP WIND SHEAR
ISSUES BECAUSE THERE WILL BE INCREASING WESTERLY WINDS IN THE 1000
TO 2000 FOOT LAYER OVERNIGHT. TAKE OFFS AND LANDINGS MIGHT BE
BUMPY AS PLANES MOVE THROUGH THAT LAYER BETWEEN THE LIGHTER WINDS
NEAR THE SURFACE AND THE WESTERLY WINDS OF 35 TO 50 KNOTS ALOFT.

THE WIND SHEAR ISSUES WILL LIKELY ABATE AROUND 14Z WEDNESDAY
MORNING WITH DAYTIME HEATING. HOWEVER...VERY GUSTY WESTERLY WINDS
WILL DEVELOP AS THE BOUNDARY LAYER MIXES OUT. WIND GUSTS COULD
APPROACH 40 KNOTS DURING THE LATE MORNING AND EARLY AFTERNOON.

THE KINL AREA WILL LIKELY SEE A PERIOD -RA AND MVFR CEILINGS LATE
TONIGHT AND TOMORROW MORNING DUE TO ITS PROXIMITY TO A DEEP AREA
OF LOW PRESSURE THAT WILL MOVE THROUGH SOUTHERN MANITOBA AND NW
ONTARIO.


&&

.PRELIMINARY POINT TEMPS/POPS...
DLH  60  78  59  82 /  40   0   0   0
INL  57  72  54  80 /  10  30  10  10
BRD  62  80  59  83 /   0   0   0   0
HYR  61  79  56  81 /  40   0   0   0
ASX  63  81  59  84 /  40   0   0   0

&&

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

$$

UPDATE...GSF
SHORT TERM...JJM
LONG TERM...CLC
AVIATION...GROCHOCINSKI


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