000
FXUS63 KMPX 251100
AFDMPX

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE TWIN CITIES/CHANHASSEN MN
600 AM CDT SAT MAY 25 2013

.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 344 AM CDT SAT MAY 25 2013

INITIAL SHIELD OF WAA SHOWERS THAT WAS DEPICTED WELL ON 310K
ISENTROPIC SFC ON THE NAM/GFS IS FADING AWAY ACROSS WRN WI AS THIS
BATCH OF FORCING WEAKENS AND DIVES SOUTHEAST. IN ITS WAKE...WE HAVE
WAA AT H85...BUT THE DEEPER MOISTURE HAS PUSHED EAST...SO PRECIP HAS
CUT OFF PRETTY QUICK. WITH THE WAA AND WEAK MOISTURE
TRANSPORT...SHOULD BE ABLE TO GET SOME LIGHT SHOWERS/SPRINKLES
ACROSS MN THIS MORNING...BUT NOT MUCH MORE THAN THAT.

BEST CHANCE FOR RAIN TODAY WILL BE ACROSS SRN MN. WARM FRONT NOW CAN
BE FOUND ACROSS SOUTH CENTRAL NEB INTO NE KAN...WITH A STRONG LLJ
OVERRUNNING IT. THIS HAS GENERATED AN MCS OVER ERN NEB THIS MORNING.
THUNDER STARTING TO INCREASE ACROSS IA AS WELL AS THE LLJ HAS SLOWLY
WORKED EAST. MOST OF THIS THUNDERSTORM ACTIVITY WILL REMAIN SOUTH OF
MN THROUGH THE DAY...BUT ALL HI-RES MODELS SHOW SOME OF THIS
MOISTURE FROM IA SNEAKING UP INTO SOUTH CENTRAL MN THROUGH
MORNING...WHERE SOME HIGH CHANCE/LIKELY POPS ARE CONTINUED THROUGH
THE MORNING HOURS. FOR THE AFTERNOON...PRECIP LOOKS TO SHUT
OFF...BUT WE WILL BE STUCK WITH FAIRLY BROAD CLOUD COVER...WITH THE
ONLY HOPE FOR SOME BREAKS ACROSS THE NE MPX CWA THANKS TO THE
INFLUENCE OF A DRY SFC HIGH THAT WILL BE SPLAYED OUT ACROSS THE
GREAT LAKES. GIVEN THE CLOUD COVER WILL BE A COOL DAY...WITH
TEMPERATURES IN SOUTH CENTRAL MN LIKELY STAYING IN THE 50S THANKS TO
BETTER RAIN CHANCES AND THICKER CLOUD COVER.

FOR TONIGHT...ALL MODELS SHOW ANOTHER ROUND OF CONVECTION RIDING
ALONG NORTH OF THE WARM FRONT...KIND OF LIKE WHAT WE HAVE SEEN
OVERNIGHT TO OUR SOUTHWEST. QUESTION BECOMES HOW FAR NORTH DOES THE
ACTIVITY MAKE IT. CONSENSUS PLACEMENT FROM THE WARM FRONT PLACES IT
BY 12Z SUNDAY MORNING FROM THE BLACK HILLS...DOWN THROUGH
YANKTON...SD AND THEN DOWN TO THE CENTRAL IA/MO BORDER. ONCE
AGAIN...WILL SEE A LLJ OVERRUNNING THIS FRONTAL FEATURE...WHICH
SHOULD GENERATE YET ANOTHER MCS. GIVEN THE FRONTS PLACEMENT TO OUR
SOUTHWEST...BEST CHANCES FOR THUNDERSTORMS TONIGHT WILL BE SOUTH OF
THE UPPER MN RIVER IN SW MN INTO SC MN. FOR TIMING...FAVORED HIGHEST
POPS TO AFTER 6Z...AS CONVECTION SHOULD FIRE THIS EVENING OVER SE
SODAK INTO NE NEB...THEN HEAD TOWARD SW/SC MN. ALL OF THIS ACTIVITY
WOULD BE ELEVATED...SO SEVERE THREAT LOOKS MINIMAL...WITH THE MAIN
IMPACT BEING THE POTENTIAL FOR HEAVY RAIN...AS WE HAVE SEEN THIS
EVENING IN NEB.

.LONG TERM...(SUNDAY THROUGH FRIDAY)
ISSUED AT 344 AM CDT SAT MAY 25 2013

THE LONG TERM PERIOD CONTINUES TO LOOK INCREASINGLY WET AND
STORMY. THIS IS DUE TO THE REGION BEING SANDWICHED BETWEEN A
BUILDING UPPER HIGH ALONG THE EASTERN SEABOARD... WHILE A VERY
DEEP TROUGH PUSHES INTO THE WESTERN HALF OF THE UNITED STATES.
THERE SHOULD BE A ROUND OF CONVECTION PASS ACROSS SOUTHERN MN
SUNDAY MORNING...VERY SIMILAR TO WHAT HAS BEEN ONGOING OVERNIGHT
ACROSS NE/IA. THE STORMS TO OUR SOUTH CURRENTLY HAVE BEEN BASICALLY
SUB SEVERE... BUT VERY EFFICIENT RAIN PRODUCERS... WITH UPWARDS OF
1.75 INCHES OF RAIN IN THREE HOURS. THIS IS THE TREND EXPECTED
SUNDAY MORNING ACROSS SOUTHERN MN... ESPECIALLY THE I-90
CORRIDOR. THEREAFTER... A SIGNIFICANT DIMINISHING TREND IN THE
PRECIPITATION FOR SUNDAY AFTERNOON AND EVENING WITH THE NMM/ARW
WRF/S IN AGREEMENT.

MEMORIAL DAY IS LOOKING A LITTLE WORSE NOW WITH EVEN THE ECMWF
DRIVING A WAVE OF CONVECTION ACROSS THE FA DURING THE DAY AND
EVENING. JUST GENERAL THUNDER INDICATED ON SWODY2 WHICH SEEMS
REASONABLE WITH THE MAIN WARM FRONTAL BOUNDARY MEANDERING FROM THE
CENTRAL PLAINS TO THE LOWER OHIO VALLEY. AGAIN... THE CONCERN WILL
BE LOCALIZED HEAVY RAINFALL. THE DETERMINISTIC RUNS WOULD ALSO
SUGGEST ANOTHER ROUND OF CONVECTION FOR US LATE MONDAY NIGHT AND
TUESDAY MORNING... ESPECIALLY ACROSS SOUTHERN MN.

THIS REPEATING ROUNDS OF POTENTIAL CONVECTION IS DISTURBING WITH
AREAS OF SOUTHERN AND ESPECIALLY SOUTHEAST MN RUNNING WELL ABOVE
NORMAL ON RAINFALL FOR THE MONTH OF MAY. THE THREAT FOR FLASH
FLOODING WILL BE ON THE INCREASE. IT WAS POINTED OUT ON FRIDAY
IN THE WEATHERTALK FROM DR SEELY AT THE UMN THAT SINCE MARCH
1ST...(METEOROLOGICAL SPRING) IT HAS BEEN ONE OF THE WETTEST IN
HISTORY FOR MANY AREAS OF MN. ADD THIS TO THE CIPS ANALOGS
FOR 5 DAYS FROM NOW AND ONE SEES A VERY WET PATTERN ACROSS ALL OF
THE REGION WITH 2 INCHES OF RAINFALL EXCEEDING 30 PERCENT
PROBABILITY WITH EVEN WIDESPREAD 3 INCHES HAVING A 10 PERCENT
PROBABILITY. THIS IS IN ADDITION TO THE RAINS SUNDAY THROUGH
TUESDAY. NOT SURPRISING THEN ARE THE RUN TOTALS FROM THE GFS AND
ECMWF THROUGH NEXT FRIDAY WHICH PAINT THE LANDSCAPE WITH 2 TO 4
INCHES OF RAIN... WITH 4 INCHES OR MORE SOUTH OF US. DIGRESSING
FOR A MOMENT... ONE OF THE MONTHS/YEARS THAT HAS SHOWN UP IN THE
CIPS ANALOGS RECENTLY IS JULY 1993... WITH RECORD FLOODING IN THIS
PART OF THE COUNTRY. A REVIEW FROM NCDC SHOWED LOW PRESSURE ALOFT
OVER THE WESTERN HIGH PLAINS WITH A STRONG SW JET AT 250 MB ACROSS
OUR AREA. THE BERMUDA HIGH HAD PUSHED INTO THE SOUTHEAST UNITED
STATES WITH ORGANIZED 850 MB WINDS FROM THE WESTERN GULF OF MEXICO
TO THE WESTERN GREAT LAKES. HENCE... THE FLOODING POTENTIAL IS A
BIG CONCERN FOR THE WEEK AHEAD AS THE PATTERN IN THE SUMMER OF
1993 MIMICS OUR WEEK AHEAD QUITE WELL.

FINALLY... AND JUST AS IMPORTANT... WILL BE THE THREAT FOR SEVERE
WEATHER NEXT WEEK AS THE WARM FRONT LIFTS NORTH INTO OUR AREA
BEGINNING ON TUESDAY. NOT TOO CONCERN ABOUT SEVERE ON SUNDAY. THE
CHANCE INCREASES SOME ON MONDAY (ISOLATED)...ESPECIALLY IF
AFTERNOON CONVECTION DEVELOPS AS DEEP LAYER SHEAR RISES. THEN FROM
TUESDAY ONWARD THERE IS SEVERE POTENTIAL EACH DAY. THE CIPS
ANALOGS CONTAIN MANY SEVERE REPORTS FOR US FOR THE MIDDLE OF NEXT
WEEK WITH SEVERE PROBABILITIES FROM 15 TO 30 PERCENT FOR THE
ENTIRE FA USING THE TOP 8 ANALOGS. A COLD FRONT MAY MOVE ACROSS
THE FA FROM FRIDAY INTO SATURDAY...DIMINISHING THE SEVERE WEATHER
THREAT.

&&

.AVIATION...(FOR THE 12Z TAFS THROUGH 12Z SUNDAY MORNING)
ISSUED AT 600 AM CDT SAT MAY 25 2013

LOTS OF CONVECTION ON THE RADAR...BUT IT IS ALL WELL TO THE SOUTH.
MAY SEE A FEW SPRINKLES/LIGHT SHOWERS ACROSS MN THROUGH THE
MORNING...WITH ANYTHING MORE SUBSTANTIAL STAYING CONFINED TO THE
I-90 CORRIDOR. FOR THE REST OF THE DAY...WILL HAVE TO TRACK MVFR
CIGS EMANATING FROM THE TSRA ACTIVITY IN IOWA. CONTINUED TO FAVOR A
HRRR/RAP DEPICTION FOR THE HANDLING OF THESE LOW CLOUDS...KEEPING
MVFR CIGS DURING THE DAY CONFINED TO RWF. WITH SE FLOW...NAM ALONG
WITH THE RAP SHOW MVFR CIGS WORKING NW INTO NODAK...WHICH SHOULD
BRING MVFR CIGS TO AXN THIS AFTERNOON OR EVENING. MSP/STC LOOK TO BE
SITTING ON THE EDGE OF THE MVFR CIGS BY THE END OF THE TAF PERIOD
AND AT THIS POINT...STUCK WITH VFR CONDITIONS AT BOTH LOCATIONS
THROUGHOUT...THOUGH CERTAINLY SOME MVFR CIGS COULD BE SEEN AFTER
06Z. EXPECT ANOTHER ROUND OF THUNDERSTORMS TONIGHT...THOUGH WITH
WARM FRONT DRIFTING NORTH...STORMS SATURDAY NIGHT SHOULD BE A BIT
FARTHER NORTH OF WHERE THEY ARE NOW. BEST CHANCE FOR THUNDER LOOKS
TO BE ALONG/SOUTH OF THE MN RIVER...SO INTRODUCED SOME VCTS TO THE
END OF THE RWF TAF. FOR WINDS...THEY WILL BE REMARKABLY PERSISTENT
THIS PERIOD OUT OF THE SOUTHEAST...WITH WINDS TODAY EXPECTED TO
INCREASE TO NEAR WHAT WAS SEEN FRIDAY ACROSS MN.

KMSP...CONFIDENCE HIGH IN TAF THROUGH 06Z. AFTER 06Z...MVFR CIGS
THAT WILL BE SOUTHWEST OF THE FIELD WILL START TO PUSH NORTHEAST AND
COULD BEGIN TO IMPACT THE FIELD. HOWEVER...STICKING WITH THE THEME
OF THE GFS...WITH CIGS REMAINING ABOVE 4K FT. WILL ALSO HAVE TO
WATCH HOW ACTIVITY EVOLVES TO THE SOUTHWEST LATE TONIGHT...AS THERE
ARE INDICATIONS FROM THE GFS/ECMWF THAT SOME LIGHT ACTIVITY COULD
APPROACH THE FIELD SUNDAY MORNING. HOWEVER...AT THIS TIME...WITH THE
WARM FRONT EXPECTED DOWN ACROSS CENTRAL IOWA...FEEL BETTER SHRA/TSRA
CHANCES SUNDAY MORNING WILL BE DOWN ACROSS SOUTH CENTRAL MN...SO
KEPT ANY SORT OF PRECIP MENTION OUT OF THE TAF.

/OUTLOOK FOR KMSP/
SUN...CHC MVFR OR LOWER CIGS. CHC SHRA/TSRA. WINDS SE 10-15 KTS.
MON...CHC MVFR OR LOWER CIGS. CHC SHRA/TSRA. WINDS SE 10 KTS.
TUE...CHC MVFR OR LOWER CIGS. TSRA LIKELY. WINDS SSE 5-10 KTS.

&&

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

$$

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