000
FXUS63 KMPX 170503 AAA
AFDMPX

AREA FORECAST DISCUSSION...UPDATED
NATIONAL WEATHER SERVICE TWIN CITIES/CHANHASSEN MN
1203 AM CDT FRI MAY 17 2013

.UPDATE...

UPDATED FOR THE 06Z AVIATION DISCUSSION BELOW.

.SHORT TERM...(THIS EVENING THROUGH FRIDAY)
ISSUED AT 207 PM CDT THU MAY 16 2013

TWO WEATHER CONCERNS FOR LATE TONIGHT...AND THRU FRIDAY AS
INITIAL VERY DRY ATMOSPHERE WILL SUPPRESS CONVECTIVE TO THE
SW THIS AFTN/EARLY EVENING. HOWEVER..A VERY POTENT DISTURBANCE
NOTED ON SATELLITE MOVING ACROSS NEBRASKA WILL EVENTUALLY MOISTEN
UP THE ATMOSPHERE...AND BASED ON THE AMOUNT OF ENERGY ASSOCIATED
WITH THE COMPLEX OF TSRA/SHRA ACROSS NEBRASKA...PRECIPITATION WILL
SPREAD ACROSS SW/SC MN BY MIDNIGHT. HOWEVER...DEPENDING UPON THE
LOW LEVEL JET ORIENTATION TONIGHT...AND THE INTERACTION OF THE
DISTURBANCE/PLUS HOW FAST THE ATMOSPHERE MOISTENS UP...WILL DEPEND
ON HOW FAR N/NW THIS AREA OF PRECIPITATION SPREADS ACROSS OUR FA.
BEST SCENARIO IS TO CONTINUE WITH HIGH POPS ALONG THE IA/MN
BORDER...NORTHWARD TO MSP/WC WI WHERE THE BEST MOISTURE ADVECTION
AND ENERGY WILL OCCUR. ELSEWHERE...PRECIPITATION WILL LIKELY OCCUR
BUT RAINFALL AMTS WILL BE SUPPRESS AND LIKELY MUCH LOWER THAN
EXPECTED. THIS AREA OF PRECIPITATION WILL LIKELY SPREAD NE OF THE
FA BY LATE FRIDAY AFTN...WITH MAINLY AFTN ISOLD CONVECTION
POSSIBLE IN SOUTHERN/CENTRAL MN DUE TO THE INCREASED INSTABILITY.

.LONG TERM...(FRIDAY NIGHT THROUGH THURSDAY)
ISSUED AT 344 PM CDT THU MAY 16 2013

THE LONG TERM PORTION OF THE FORECAST IS A DAMP ONE. A LARGE UPPER
TROUGH OVER THE INTER-MOUNTAIN REGION OF THE WEST AT THE START OF
THE PERIOD WILL BECOME NEGATIVE TILT THROUGH THE WEEKEND... AND
THEN TRANSITION INTO A CLOSED UPPER LOW OVER THE NORTHERN PLAINS
BY MONDAY. THE SLOW PROGRESSION OF THIS FEATURE IS TIED TO AN
OMEGA BLOCK THAT DEVELOPS OVER THE NORTH ATLANTIC. AS TIME
PROGRESSES NEXT WEEK...WE ACTUALLY HAVE A SMALL REX BLOCK OVER THE
NORTHERN PLAINS AND CENTRAL CANADA. TIMING BETWEEN THE MODELS
WITH THE UPPER LOW IS RATHER EXCEPTIONAL.

AT THE SURFACE...A WARM FRONT ACROSS FAR SOUTHERN MN AND WI FRIDAY
EVENING WILL LIFT SLOWLY NORTHWARD INTO CENTRAL MN AND WEST
CENTRAL WI BY SATURDAY EVENING AND INTO THE NORTHERN PORTIONS OF MN
AND WI BY SUNDAY MORNING. SHOWER AND THUNDERSTORM CHANCES WILL BE
BEST ALONG AND NORTH OF THE ADVANCING FRONT WITH HIGH CHANCE TO
LIKELY POPS IN PLACE. ONE CONCERN IS THAT A MID LEVEL CAP WILL DEVELOP
IN THE WAKE OF THE WARM FRONT...WITH LITTLE OR NO POPS ACROSS MUCH
OF THE AREA SATURDAY NIGHT AND EARLY SUNDAY. LATER SHIFTS MAY NEED
TO DRIVE DRY WEATHER FARTHER NORTH AND WEST THAN CURRENTLY
FORECAST. THE THREAT FOR SEVERE STORMS STILL HAS MERIT OVER WEST
CENTRAL MN AS THE NOSE OF THE LOW LEVEL JET PUSHES IN FROM
EASTERN SD DURING THE EVENING ALONG WITH MODEST SHEAR AND CAPE.

SUNDAY IS MORE PROBLEMATIC AS LITTLE WAVES RIDE NORTHWARD IN THE
UPPER FLOW ACROSS THE FA. LIKELY POPS IN PLACE FOR THE AFTERNOON.
SEVERE CHANCES ARE HIGHEST ACROSS SOUTHERN MN WHERE THE BEST CAPE
AND SHEAR ALIGN DURING THE AFTERNOON AND EVENING. EVENTUALLY A
COLD FRONT WILL PASS ACROSS THE FA FROM MONDAY INTO TUESDAY WITH
THE SURFACE LOW CAPTURED BY THE UPPER LOW IN THE EASTERN DAKOTAS.
THE VERTICALLY STACKED LOW WILL THEN MOVE SLOWLY EASTWARD ACROSS
THE FA THROUGH THURSDAY WITH DRY WEATHER NOT RETURNING UNTIL
PERHAPS FRIDAY. HIGH TEMPERATURES WILL BEGIN WELL ABOVE NORMAL FOR
THE WEEKEND BUT THEN TRANSITION TO AT OR BELOW SEASONAL VALUES
FROM TUESDAY ONWARD.

MODEL QPF FOR THE ENTIRE FORECAST PERIOD (SHORT AND LONG) IS WHERE
THE BIGGEST DISCREPANCIES EXISTS. THE TREND TODAY IS FOR THE
HEAVIER TOTAL AMOUNTS OF RAIN TO BE PROJECTED ACROSS OUR FAR
WESTERN AND NORTHERN FA AS WELL AS POINTS TO THE WEST AND NORTH
(EASTERN DAKOTAS/NORTHERN MN). SEVERAL INCHES OF RAIN ARE
POSSIBLE FROM TONIGHT THROUGH THE WEEKEND. FORTUNATELY...IT SHOULD
COME IN PIECES AND WE HAVE HAD A RECENT DRY SPELL. HOWEVER... QPF
AMOUNTS STILL BARE WATCHING.

&&

.AVIATION...(FOR THE 06Z TAFS THROUGH 06Z FRIDAY NIGHT)
ISSUED AT 1151 PM CDT THU MAY 16 2013

OUTSIDE OF FAR SOUTHERN MN...MOST OF MN/WI REMAINS QUITE DRY EARLY
THIS MORNING. AS A RESULT...JUST NOT CONFIDENT SHOWERS WILL BE
WIDESPREAD TOWARD SUNRISE. THE THUNDERSTORM ACTIVITY IN IA/NE/SD
EARLY THIS MORNING SHOULD CONTINUE TO SLIDE EAST WITH TIME. BACK
FARTHER TO THE WEST IN NE...THERE IS A SECOND BATCH OF SHOWERS
THAT COULD IMPACT KMSP/KRNH/KEAU LATER ON THIS MORNING. VIS AND
CIGS AREN`T A PROBLEM THIS MORNING...WITH JUST BRIEF PERIODS OF
MVFR RIGHT UNDER THUNDERSTORMS...AND MOST OF THESE WILL SLIDE
SOUTH OF THE TAF SITES. WINDS WILL REMAIN BREEZY THROUGH THE DAY.

KMSP...

LIGHT RAIN EXPECTED FOR A COUPLE HOURS VERY EARLY THIS
MORNING...UNTIL ABOUT 0730Z OR SO...THEN A BREAK...AND THEN THE
POTENTIAL FOR A FEW MORE SHOWERS LATER ON THIS MORNING. THE AMOUNT
OF INSTABILITY IS NOT AS GOOD HERE AS IN IA/NE. SO...THUNDER WILL
BE MUCH HARDER TO GET AT THE AIRPORT. BREEZY E-SE WINDS WITH
LITTLE CHANGE IN WIND DIRECTION THROUGH THE TAF PERIOD. ONLY SMALL
CHANCE OF MVFR CEILINGS/VISIBILITY...NOT ENOUGH CONFIDENCE TO
INCLUDE AT THIS POINT.

/OUTLOOK FOR KMSP/

SAT...VFR/MVFR CIGS. CHC IFR IN HEAVIER TSRA. SE-S WINDS 5-10 KTS.
SUN...VFR/MVFR CIGS. CHC IFR IN HEAVIER TSRA. S-SE WINDS 8-12 KTS.

&&

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

$$

SHORT TERM...JLT
LONG TERM...RAH
AVIATION...CLF