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000
FXUS63 KMPX 222223
AFDMPX

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE TWIN CITIES/CHANHASSEN MN
356 PM CDT WED MAY 22 2013

.SHORT TERM...(THIS EVENING THROUGH THURSDAY)
ISSUED AT 1219 PM CDT WED MAY 22 2013

WE ARE FINALLY SEEING SOME PROGRESSION... ALBEIT GRUDGINGLY
SLOW... IN THE UPPER LEVEL PATTERN OVER THE CONUS. THE UPPER LOW
WHICH HAS BEEN OVER OUR AREA FOR MANY MANY DAYS IS SLIDING EAST OF
THE REGION... GIVING WAS TO RIDGING WHICH WILL BRING FAIR SKIES
AND DRY WEATHER FOR AT LEAST A COUPLE OF DAYS. THE MODEL GUIDANCE
IS IN GOOD AGREEMENT ON THE ARRIVAL OF THE DRY AIR AND SEASONABLY
COOL TEMPERATURE FOR THE NEXT TWO DAYS... BUT CONTINUES TO SHOW
SOME VARIATION IN HOW THINGS WILL UNFOLD AFTER THAT. BUT... UNTIL
THEN THE OVERALL THEME WILL BE FOR THE DIURNALLY ENHANCED PCPN
CURRENTLY OVER THE AREA TO SHIFT SOUTHEAST OF THE AREA TONIGHT...
ALLOWING FOR SUBSIDENCE AND MUCH DRIER CONDITIONS TO MOVE IN FROM
THE NORTHWEST AS THE SURFACE HIGH OVER CENTRAL CANADA BUILDS INTO
THE REGION. THE UPSTREAM DEWPOINT DEPRESSIONS SUGGEST WE SHOULDN/T
HAVE TOO MUCH OF AN ISSUE WITH DEVELOPMENT OF FOG/STRATUS TONIGHT
ONCE THE CLOUD COVER IS SCOURED OUT... BUT THERE IS AT LEAST SOME
DEGREE OF CONCERN GIVEN HOW MUCH RAINFALL THE AREA HAS SEEN
LATELY. AT THIS POINT... IT LOOKS LIKE WE SHOULD HOLD ONTO ENOUGH
OF A GRADIENT AND SOME WINDS TO KEEP FOG LIMITED TO PATCHES IN LOW
LYING AREAS NEAR BODIES OF WATER... BUT WILL BE SOMETHING TO KEEP
AN EYE ON OVERNIGHT. THURSDAY SHOULD BRING MOSTLY SUNNY SKIES AND
DRY WEATHER TO THE AREA... WITH WARMER READINGS THAN TODAY DUE TO
THE SUNSHINE... ALTHOUGH THEY WILL STILL BE BELOW NORMAL.

.LONG TERM...(THURSDAY THROUGH TUESDAY)
ISSUED AT 410 AM CDT WED MAY 22 2013

LONG TERM FORECAST KICKS OFF WITH A GOOD LIKELIHOOD FOR AREAS OF
FROST OVER MUCH OF WEST CENTRAL WISCONSIN BY LATE THURSDAY NIGHT.
DOME OF SURFACE 1030MB HIGH PRESSURE PARKS ITSELF RIGHT OVER THIS
REGION BY FRI/12Z TIME FRAME. RADIATIONAL COOLING WILL COMBINE WITH
COLD POLAR AIR BEHIND THE EXITING 50H LOW AND MOSTLY CLEAR SKIES
TO PRODUCE GOOD SWATH OF TEMPS BOTTOMING OUT INTO THE LOWER TO
MID 30S ACROSS MUCH OF WEST CENTRAL WISCONSIN. AT THIS JUNCTURE
IT APPEARS MORE LIKELY THAT A FROST ADVISORY MAY NEED TO BE ISSUED
FOR THIS REGION EITHER LATE TONIGHT OR ON THURSDAY. BY THE WAY
...THE AVERAGE LOW TEMPERATURE FOR THIS TIME OF YEAR AT EAU IS
47 DEGREES. IN ADDITION...SCT FROST SHOULD ALSO OCCUR OVER FAR
EASTERN PORTIONS OF EAST CENTRAL MN TOMORROW NIGHT.

SHORT LIVED 50H RIDGE OVER MN/WI WILL BEGIN TO ERODE LATE FRIDAY
AS PACIFIC NORTHWEST STORM SYSTEM TREKS INTO THE FAR WESTERN
DAKOTAS. WARM FRONTAL BOUNDARY EMANATING FROM THIS SYSTEM WILL
OVERSPREAD MUCH OF SOUTHERN HALF OF MN BY LATE FRIDAY NIGHT INTO
LATE SATURDAY MORNING. THIS WILL BE CATALYST FOR LIKELY CONVECTIVE
ACTIVITY OVER MUCH OF WESTERN HALF OF FA DURING THIS TIME FRAME.
BOTH GFS40 AND EUROPEAN HAVE SUPPORTING SOLUTIONS FOR THIS INITIAL
WAVE OF ACTIVITY. EUROPEAN CONTINUES TO TREND TOWARD KEEPING MUCH
OF THE NORTHEASTERN PORTION OF MN AND WEST CENTRAL WISCONSIN DRY
INTO EARLY SUNDAY AFTN. DECIDED TO RUN WITH THE GFS40 SOLUTION DUE
TO ITS PLACEMENT OF THE CLOSED 50H LOW OVER THE WA/OREGON REGION
AT 18Z TODAY...AND ITS CURRENT HANDLING OF PCPN OVER OUR CWA.

WITH THAT SAID SCATTERED SHOWERS AND THUNDERSTORMS WILL PREDOMINATE
OVER THE REGION THROUGH THE WEEKEND...WITH A BROAD AREA OF SURFACE
HIGH PRESSURE POISED TO INFILTRATE WESTERN SODAK BY LATE SATURDAY
NIGHT...BUT MOVE LITTLE INTO EARLY MONDAY MORNING. STRONG THETA
E ADVECTION ANTICIPATED OVER SW AND SOUTH CENTRAL MN MONDAY
MORNING...COUPLED WITH STRONG 250MB DIVERGENCE COUPLETS...AND
MODERATE LOW LEVEL JET. IF THINGS PAN OUT...COULD BE A CHANCE
FOR ISOLATED TO SCT SEVERE STORMS SUNDAY EVENING. BROAD SFC CYCLONE
NOTED ABOVE FORGES INTO A STRONG 995MB SURFACE LOW OVER WESTERN
KANSAS BY MONDAY EVENING. INVERTED TROUGH FROM THIS SYSTEM WILL
BE SEEN THROUGH EASTERN DAKOTAS INTO WESTERN HALF OF MN TUESDAY
THROUGH THURSDAY. INSTABILITY ASSOCIATED WITH THIS FEATURE DEMANDED
CHANCE POPS THROUGH END OF PERIOD. MOISTURE VALUES AT LEAST THROUGH
NEXT TUESDAY SHOULD BE AROUND 1/2 OF AMOUNTS EXPERIENCED WITH CURRENT
STORM SYSTEM. THUS EXPECT ANOTHER THREE QUARTERS OF AN INCH TO
NEAR ONE AND ONE HALF INCHES FRIDAY NIGHT THROUGH TUESDAY...WITH
SOMEWHAT HEAVIER AMOUNTS THEREAFTER. VERY EARLY TO BE SURE...BUT
CURRENT ANALYSIS PORTENDS POSSIBLE STRONG COLD FRONT PUNCHING
THROUGH OUR REGION NEXT FRIDAY NIGHT INTO SATURDAY...WITH DECENT
POTENTIAL FOR MORE WIDESPREAD SEVERE WEATHER.









&&

.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z THURSDAY AFTERNOON)
ISSUED AT 1219 PM CDT WED MAY 22 2013

THE MAIN THEME FOR THE FORECAST WILL BE IMPROVING CONDITIONS FOR A
CHANGE AS THE RIDGE TO OUR NORTHWEST FINALLY WORKS INTO THE
REGION. UNTIL THAT OCCURS... HOWEVER... WE WILL CONTINUE TO DEAL
WITH MVFR AND LOCAL IFR CEILINGS THIS AFTERNOON INTO THIS
EVENING... WITH VISIBILITIES ALSO DROPPING INTO MVFR WITH RAIN AT
TIMES. CONFIDENCE IN THE OVERALL TREND OF THE FORECAST IS FAIRLY
HIGH... BUT THERE COULD STILL BE SOME SLIGHT DIFFERENCES IN TIMING
OF THINGS AND CEILINGS/VISIBILITIES COULD VARY A BIT MORE THAN
FORECAST. HOWEVER... DO NOT ANTICIPATE AS MUCH VARIABILITY OR NEED
FOR AMENDMENTS AS THE PAST FEW DAYS.

KMSP...TAF REFLECTS EXPECTED TRENDS WITH A REASONABLE DEGREE OF
CONFIDENCE OVERALL. CEILINGS THIS AFTERNOON COULD IMPROVE A BIT
QUICKER THAN SUGGESTED... BUT IT IS ALSO POSSIBLE THAT THEY WILL
STAY DOWN NEAR 1000 FT AGL THROUGH THE AFTERNOON. VISIBILITIES
SHOULD BE VFR EXCEPT WITH PATCHES OF RAIN WHEN THEY COULD DROP AS
LOW AS 3-4SM FOR A BRIEF TIME. WINDS WILL BE CONSISTENT FROM THE
N/NNE THROUGH THE PERIOD. TIMING OF THE BIG IMPROVEMENT TO VFR
TONIGHT MAY DIFFER BY +/- 2 HOURS OR SO FROM FORECAST.

/OUTLOOK FOR KMSP/
THURSDAY NIGHT...VFR CONDITIONS EXPECTED. EAST WIND LESS THAN 10
KT BECOMING SOUTHEAST.
FRIDAY AND FRIDAY NIGHT...VFR CONDITIONS EXPECTED. SOUTHEAST WIND
5 TO 15 KT.
SATURDAY...BRIEF MVFR CEILINGS POSSIBLE WITH A CHANCE OF
SHRA/TSRA. SOUTHEAST WIND 10 TO 20 KT.
SATURDAY NIGHT...MVFR CEILINGS AND VISIBILITIES POSSIBLE WITH A
CHANCE OF SHRA/TSRA. SOUTHEAST WIND 10 TO 20 KT.
SUNDAY...MVFR CEILINGS AND VISIBILITIES POSSIBLE WITH A CHANCE OF
SHRA/TSRA... BRIEF IFR CONDITIONS POSSIBLE. SOUTHEAST WIND 10 TO
20 KT.


&&

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

$$

SHORT TERM...
LONG TERM...RAH
AVIATION...