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000
FXUS63 KMPX 172115
AFDMPX

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE TWIN CITIES/CHANHASSEN MN
415 PM CDT MON JUN 17 2013

.SHORT TERM...(TONIGHT AND TUESDAY)

COLD FRONT MOVING SOUTH ACROSS THE CENTRAL PORTION OF THE CWA THIS
AFTERNOON. LATEST MESOSCALE OBSERVATION SHOWING MUCAPE 500-1000
J/KG WITH EFFECTIVE SHEAR VALUES TO 35 KTS FROM EAST CENTRAL MN
INTO WESTERN WI. ALREADY GETTING SOME SMALL SUPERCELLS DEVELOPING
OVER THIS REGION...ALONG WITH SOME REPORTS OF LARGE HAIL. DCAPE
VALUES INCREASE OVER 800 J/KG...MAINLY ALONG AND SOUTH OF I94. IF
CELLS DO DROP INTO THIS REGION AND ARE ABLE TO DRAW IN SOME OF
THIS MORE UNSTABLE AIR...WE COULD GET SOME STRONG WINDS AS WELL.
ACTIVITY SHOULD REMAIN ISOLATED ENOUGH TO PREVENT WATCH ISSUANCE
PER LATEST MCD FROM SPC.

ACTIVITY WILL LINGER INTO EARLY EVENING AND OVERALL TREND WILL
LIKELY WANE. THEN THE MAIN UPPER TROUGH...OVER NORTH
DAKOTA...MOVES INTO WESTERN MN LATER TONIGHT. THIS WILL SPREAD
SOME CHANCE POPS OVER THE AREA LATER TONIGHT INTO TUESDAY. WILL
TRAIL POPS OFF OVER WEST CENTRAL MINNESOTA LATER TONIGHT AND WILL
LINGER LONGEST INTO SOUTH CENTRAL MN...TUESDAY AFTERNOON. DONT
ANTICIPATE ANYTHING SEVERE FOR TUESDAY.

CLOUDS WILL LINGER INTO TUESDAY AS WELL...WITH NEGATIVE CU RULES
OVER THE REGION. HOWEVER...SHOULD SEE OVERALL CLEARING DURING THE
AFTERNOON...FROM NORTHWEST TO SOUTHEAST. EXPECT TEMPERATURES TO
REMAIN IN THE 70S ACROSS THE CWA TUESDAY AFTERNOON.

.LONG TERM...(TUESDAY NIGHT THROUGH MONDAY)
ISSUED AT 411 PM CDT MON JUN 17 2013

THE EXTENDED PERIOD IS STILL LOOKING RATHER SUMMER-LIKE AND
POTENTIALLY ACTIVE AS THE MPX AREA FINDS ITSELF ON THE EDGE OF THE
SUBTROPICAL RIDE THAT WILL BE SLOWLY SHIFTING FROM THE SRN PLAINS
THIS WEEKEND OVER TO THE ROCKIES NEXT WEEK. THIS LOOKS TO BRING WITH
IT WARM AND HUMID CONDITIONS...ALONG WITH THE POTENTIAL FOR SEEING
SEVERAL ROUNDS OF MCS/S ACROSS THE UPPER MIDWEST.

THE DRY PERIOD DURING THE LONG TERM LOOKS TO BE SHORT-LIVED...
LASTING ALL OF TUESDAY NIGHT. BY WEDNESDAY AFTERNOON...ALL GUIDANCE
SHOW A SHORT WAVE WORKING ACROSS THE LARGE SCALE RIDGE CENTERED OVER
THE CENTER OF THE CONUS. MAIN LLJ WILL BE ORIENTED AT THIS TIME FROM
NEB UP ACROSS THE DAKOTAS INTO NE MONTANA. HOWEVER...ALL GUIDANCE
SHOWS A WEAKER FINGER OF THE LLJ EXTENDING NE FROM SW MN UP TOWARD
THE ARROWHEAD OF MN. COMBINE THIS LLJ WITH THE SHORTWAVE AND MUCAPES
INCREASING TO BETWEEN 1000 AND 2000 J/KG AND YOU HAVE MORE THAN
ENOUGH SUPPORT FOR THE CHANCE OF THUNDERSTORMS CURRENTLY IN THE
FORECAST.

WEDNESDAY NIGHT...THE LLJ FROM THE DAKOTAS BEGINS TO LAY OVER INTO
MN...AND WITH IT THE DEEP TROPICAL MOISTURE ARRIVES. BY THURSDAY
AFTERNOON...THE GFS BRINGS PWATS OF 1.5-2 INCHES UP INTO MN/WI
/BETTER THAN 150% OF NORMAL/ AND KEEPS THE PWATS UP THERE FROM
THURSDAY RIGHT THROUGH THE WEEKEND AND INTO NEXT WEEK. TO GO ALONG
WITH THIS...BY FRIDAY...BOTH THE GFS AND ECMWF SHOW DEWPOINTS
INCREASING INTO THE LOWER 70S THAT STAY THERE THROUGH THE WEEKEND.
THIS TYPE OF WEATHER PATTERN IS A CLASSIC SUMMERTIME MCS
SETUP...WITH MULTIPLE COMPLEXES LIKELY TO MOVE AROUND THE NRN EDGE
OF THE SUBTROPICAL RIDGE. THIS FAR OUT...VERY DIFFICULT TO FORECAST
EXACT TIMING/PLACEMENT OF ANY OF THIS ACTIVITY...AS STORMS ONE
NIGHT WILL PLAY A SIGNIFICANT ROLE IN WHERE STORMS THE NEXT DAY SHOW
UP AND SO ON. AS A RESULT...THE EXTENDED PERIOD IS FULL OF ENDLESS
CHANCE POPS OVER MOST OF THE AREA. THERE WILL CERTAINLY BE DRY
PERIODS IN THE EXTENDED...BUT STILL LOOK TO SEE A FEW ROUNDS OF
STORMS. WITH THE 17.12 MODEL RUNS...THE GFS HAS TOTAL QPF BY TUESDAY
OF 2-4 INCHES ACROSS THE NRN HALF OF MN...WHILE THE ECMWF HAS
SIMILAR AMOUNTS FOR THE SOUTHERN HALF OF THE STATE. WITH ALL OF
THIS...WILL HAVE TO KEEP AN EYE ON BOTH THE SEVERE WEATHER AND
FLOODING SIDE OF THINGS.

AS FOR TEMPERATURES...AT THE VERY LEAST TEMPERATURES WILL BE ABOVE
NORMAL IN THE EXTENDED...AS LOWS STRUGGLE TO GET OUT OF THE 70S. FOR
TEMPERATURES...THE BIG QUESTION WILL BE HOW MUCH CLOUD COVER IS
AROUND EACH DAY. BUT...BY FRIDAY...THE ECMWF/GFS SHOW 925 MB TEMPS
INCREASING INTO THE MID/UPPER 20S C. SO AS LONG AS THERE IS NOT TOO
MUCH CLOUD COVER HANGING AROUND...THEN FRIDAY THROUGH THE WEEKEND
WILL PROVIDE SOME OPPORTUNITIES TO TOP THE 90 DEGREE MARK...
ESPECIALLY SOUTH.

&&

.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z TUESDAY AFTERNOON)
ISSUED AT 128 PM CDT MON JUN 17 2013

SURFACE FRONT DROPPING SLOWLY SOUTH OVER THE REGION DURING THE
PERIOD. SCATTERED THUNDER ASSOCIATED...SHOULD GRADUALLY WANE THIS
EVENING...WITH A DIURNAL TREND. WILL MENTION THUNDER OVER WC
WISCONSIN THIS AFTERNOON. WILL HAVE TO MONITOR EAST CENTRAL
MN...AS SREF 1 HOUR THUNDER FORECAST INDICATED COULD SEE SOME
ISOLD ACTIVITY HERE AS WELL. HAIL AND STRONG WIND GUSTS REMAIN A
POSSIBILITY...WITH STEEP LOW LEVEL LAPSE RATES AHEAD OF FRONT AND
DCAPE INCREASING TO OVER 1000 J/KG.  WILL HOLD ONTO VFR FORECAST
DURING THE PERIOD...BUT IF A STRONGER CELL MOVES THROUGH...COULD
SEE BRIEF MVFR/IFR TREND. FRONT REMAINS OVER THE SOUTHEAST INTO
THURSDAY...AND MODELS TREND SOME SCATTERED SHOWERS MOVING BACK
INTO WESTERN MN LATER TONIGHT...SPREADING SOUTHEAST TUESDAY AS
UPPER TROUGH MOVES THROUGH. SURFACE WINDS BECOMING NORTH/NORTHEAST
WITH FROPA AND EVENTUALLY EAST ON TUESDAY.

KMSP...
WILL CONTINUE VFR TREND DURING THE PERIOD. CEILINGS WILL DROP TO
4-5K FEET AS FRONT MOVES THROUGH WITH SCATTERED SHOWERS. LOW
PROBABILITY OF THUNDER WITH SYSTEM...AND LOOK LIKE BEST SHOT WILL
BE FOUND OVER WEST CENTRAL WISCONSIN INTO EARLY EVENING...SO ;EFT
THUNDER OUT FOR NOW. CLOUDS WILL LINGER INTO TUESDAY WITH CLEARING
LATE AFTERNOON...AS SYSTEM EXITS THE AREA. NORTHWEST WINDS WILL
BECOME NORTH/NORTHEAST TONIGHT...AND MORE EAST IN THE WAKE OF THE
FRONT TUESDAY. COULD SEE SOME WIND GUTS EARLY THIS AFTERNOON AHEAD
OF THE COLD FRONT...BUT WILL DIMINISH TONIGHT.

/OUTLOOK FOR KMSP/
TUE...VFR. SLIGHT CHC SHRA EARLY. ESE WINDS 5 KTS.
WED...VFR. CHC OF MVFR AFTN/EVE SHRA/TS. S WINDS 5-10 KTS.
THU...VFR. CHC OF MVFR SHRA/TS. SSE WINDS 10 KTS.


&&

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

$$

SHORT TERM...DWE
LONG TERM...MPG
AVIATION...DWE