Area Forecast Discussion
Issued by NWS Twin Cities, MN

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FXUS63 KMPX 040422
AFDMPX

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE TWIN CITIES/CHANHASSEN MN
1122 PM CDT FRI JUL 3 2015

.SHORT TERM...(THIS EVENING THROUGH SATURDAY)
ISSUED AT 320 PM CDT FRI JUL 3 2015

THE SHORT TERM CONCERNS REMAIN EXTENT OF ANY CONVECTION ALONG THE
WEAK SURFACE BOUNDARY TONIGHT AND SMOKE/FOG ENCROACHMENT TONIGHT
INTO SATURDAY.

LATEST HIRES MODELS/CAMS CONTINUE INDICATE SOME SMALL CHANCE OF
ISOLATED/WIDELY SCATTERED TSRA OVER EASTERN PORTION OF THE CWA INTO
THE EVENING AS BOUNDARY SAGS IN.  WILL CONTINUE THIS THREAT THROUGH
ABOUT 03Z FROM EXTREME EAST CENTRAL MN INTO WEST CENTRAL WISCONSIN.
LATEST SPC MESOANALYSIS QUITE UNSTABLE ALONG THE BOUNDARY...NOW
MOVING INTO EXTREME NORTHEAST PORTION OF THE CWA. EXPECT THIS TO
GRADUALLY END AFTER SUNSET.

SMOKE IS GRADUALLY FILTERING INTO THE NORTHWEST CWA...AND IS
EXPECTED TO CONTINUE TO DO SO.  VSBY REDUCTION HAS BEEN MINOR THUS
FAR...AFTERNOON MIXING IS PROVIDING SOME IMPROVEMENT OVER NORTHWEST
MN.  STILL...AIR QUALITY MODEL DIAGNOSTICS SHOW SMOKE AREA DROPPING
OVER CENTRAL MN DURING THE NIGHT.  WILL MENTION AREAS/PATCHY SMOKE
OVER THE NORTHWEST CWA.  THEN SOME FOG POTENTIAL TO THE FAR
EAST...ALTHOUGH SREF PROBABILITIES ARE MARGINAL.  STILL...WITH SOME
ISOLATED SHOWER ACTIVITY INTO THE EVENING...AND LIGHT WINDS AND
BOUNDARY IN THE AREA...WE COULD SEE SOME FOG FORM INTO WEST CENTRAL
WISCONSIN.

NEXT PROBLEM IS EXTENT OF ANY REDEVELOPING SHRA/TSRA INTO EASTERN
AREAS SATURDAY AFTERNOON/EVENING.  SOME MODELS STILL TRY TO DEVELOP
SOME ISOLATED ACTIVITY OVER THIS REGION MONDAY/AFTERNOON.  STILL
WILL HAVE WEAK BOUNDARY IN THE VICINITY AND MUCAPES ARE FORECAST TO
INCREASE TO 1500-2000 J/KG IN THE AFTERNOON ALONG AND NORTH OF WEAK
WARM FRONT.  WILL HOLD ONTO SLIGHT CHANCE POPS FOR ISOLATED THREAT
IN THE AFTERNOON ACROSS THE FAR EAST FOR NOW.

.LONG TERM...(SATURDAY NIGHT THROUGH FRIDAY)
ISSUED AT 320 PM CDT FRI JUL 3 2015

THE LONG TERM PORTION OF THE FORECAST WILL FEATURE THE PASSAGE OF
A COLD FRONT EARLY ON WITH COOLER TEMPERATURES RESULTING AS A
BROAD AREA OF SURFACE HIGH PRESSURE BUILDS ACROSS THE REGION.

STILL EXPECT THE EVENING OF THE FOURTH TO BE DRY...ALTHOUGH HIGH
CLOUDS WILL BE ON THE INCREASE AHEAD OF THE NEXT APPROACHING
TROUGH AND THERE WILL STILL BE SOME RESIDUAL CANADIAN WILDFIRE
SMOKE AROUND. 12Z MODELS WERE FAIRLY AGREEABLE REGARDING TIMING
OF THE NEXT FRONT TO COME...WHICH SHOULD BE ENTERING FAR WEST CENTRAL
MINNESOTA AT 00Z MONDAY. WILL LIKELY SEE STORMS SNEAK INTO THE FAR
WESTERN PART OF THE FORECAST AREA ON SUNDAY AFTERNOON...WITH SHOWERS
AND THUNDERSTORMS EXPANDING EASTWARD AND BECOMING WIDESPREAD
BETWEEN 00Z AND 12Z MONDAY. GIVEN THE ORIENTATION OF THE TROUGH
WILL BE POSITIVELY TILTED IN NATURE...DEEP LAYER SHEAR AHEAD OF
THE FRONT WILL NOT BE IMPRESSIVE. HOWEVER...STEEP MID LEVEL LAPSE
RATES AND PROGGED MIXED LAYER CAPES NEAR 2000 J/KG WILL YIELD THE
POTENTIAL FOR A FEW SEVERE STORMS. MID LEVEL HEIGHT FALLS ARE
EXPECTED AS THE ATTENDANT SHORTWAVE PIVOTS FROM THE DAKOTAS
TOWARD WEST CENTRAL MN DURING THE AFTERNOON AS WELL...WHICH WILL
AID IN THE ATMOSPHERIC DESTABILIZATION PROCESS. AFTER THE EVENING
THREAT FOR SEVERE STORMS OVER WEST CENTRAL MINNESOTA...THE PRIMARY
CONCERN MAY TRANSITION TO A HEAVY RAINFALL THREAT...AS
PRECIPITABLE WATER VALUES FORECAST TO SOAR ABOVE 2 INCHES.
WIDESPREAD RAINFALL AMOUNTS IN THE 1-2 INCH RANGE APPEAR QUITE
LIKELY.

BY 18Z MONDAY...TODAY/S 12Z RUN OF MODEL SOLUTIONS GENERALLY
POSITIONED THE FRONT ALONG OR JUST WEST OF INTERSTATE 35. MOST OF
THE SHOWERS AND THUNDERSTORMS SHOULD BE LOCATED EAST OF THERE
MONDAY AFTERNOON...WITH PRECIP ENTIRELY OUT OF THE AREA BY LATE
MONDAY EVENING.

BEHIND THE FRONT...COOLER...LESS HUMID...AND DRY WEATHER SETS IN
FOR TUESDAY. HIGHS IN THE 70S AND LOWS IN THE 50S SHOULD GENERALLY
PREVAIL. WHILE THERE ARE NO MAJOR SYSTEMS PROGGED...SEMI-ZONAL
FLOW WILL KEEP THE OPPORTUNITY FOR WEAK SHORTWAVES TO PASS OVER.
THE FIRST IS PROGGED FOR WEDNESDAY INTO THURSDAY. HAVE INCLUDED 20
POPS AT THIS POINT DUE TO LOW CONFIDENCE IN TIMING AND OVERALL
EXISTENCE OF SAID FEATURE.

&&

.AVIATION...(FOR THE 06Z TAFS THROUGH 06Z SATURDAY NIGHT)
ISSUED AT 1125 PM CDT FRI JUL 3 2015

HAZY SKIES RESULTING FROM SMOKE OVER OUR REGION ARE STILL
PERSISTING OVER CENTRAL AND WESTERN MN. IFR CIGS WILL CONTINUE AT
AXN AND STC...AND WITH AN INVERSION EXPECTED TO STRENGTHEN NEAR
THE SURFACE...THE SMOKE COULD GET TRAPPED CLOSER TO THE SURFACE BY
THE EARLY MORNING ON SATURDAY. THEREFORE...IFR CONDITIONS WILL PERSIST
THROUGH AT LEAST SUNRISE AT THESE TERMINALS...WITH LIFR POSSIBLE UNTIL
MIXING OCCURS DUE TO DAYTIME HEATING. DESPITE LIGHT SOUTHERLY WIND
DEVELOPING AT THE SURFACE SATURDAY MORNING...WNW WINDS SLIGHTLY
HIGHER UP IN THE ATMOSPHERE COULD PUSH SOME OF THE HAZE/SMOKE OVER
THE REMAINDER OF OUR TERMINALS. CURRENTLY GOING WITH LOW END VFR
THROUGH THE AFTERNOON AND EVENING...BUT MVFR VISIBILITY COULD
DEVELOP DUE TO THE SMOKE.

KMSP...SMOKE/HAZE NEAR THE SURFACE IN CENTRAL MN WILL REMAIN IN
THAT AREA THROUGH SUNRISE...SO CIGS AND VIS WILL LIKELY REMAIN AT
VFR LEVELS OVERNIGHT AND EARLY SATURDAY MORNING. HOWEVER...LATEST
SMOKE DISPERSION MODELS SHOW THIS LOWER LEVEL SMOKE MOVING
SOUTHEAST OVER MSP LATER IN THE MORNING. FOR NOW KEEPING
VISIBILITY AT 6SM THROUGH THE DAYLIGHT HOURS...BUT MVFR VISIBILITY
IS POSSIBLE IF THE LOWER LEVEL SMOKE DOES MOVE OVER THE AIRPORT.

/OUTLOOK FOR KMSP/
SAT NIGHT...MVFR POSSIBLE LATE DUE TO SMOKE. WINDS S 5-10 KTS.
SUN...VFR. TSRA WITH MVFR/IFR LIKELY LATE. WINDS S 10-15 KTS.
MON...MVFR/IFR WITH TSRA EARLY THEN VFR. WINDS NW 10 KTS.

&&

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

$$

SHORT TERM...DWE
LONG TERM...LS
AVIATION...ADL



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