419 
FXUS63 KMPX 070508 AAB
AFDMPX

AREA FORECAST DISCUSSION...UPDATED
NATIONAL WEATHER SERVICE TWIN CITIES/CHANHASSEN MN
1208 AM CDT MON JUL 7 2014

.SHORT TERM...(THIS EVENING THROUGH MONDAY)
ISSUED AT 328 PM CDT SUN JUL 6 2014

COLD FRONT HAS BEEN MAKING STEADY PROGRESS TO THE EAST AT ABOUT 20 
KTS ACROSS MN TODAY...AND AT 3PM WAS IN THE PROCESS OF WORKING 
ACROSS THE TWIN CITIES. MORNING CLOUDS SLOWED DOWN THE WARMING IN 
THE TWIN CITIES...BUT THERE IS STILL HOPE FOR OUR FIRST 90 DEGREE 
TEMP THIS YEAR AS THERE WILL BE ABOUT A 2 HOUR WINDOW WHERE WE CAN 
STILL WARM BEHIND THE FRONT BEFORE THE CAA KICKS IN. WE HAVE SEEN 
PLACES LIKE REDWOOD FALLS...GLENCOE...AND NEW ULM HIT 90 IN THIS
ZONE AND IT WILL BE HITTING THE TWIN CITIES STILL DURING PEAK
HEATING BETWEEN 3 AND 5 PM...SO DON/T GIVE UP HOPE ON THAT FIRST
90 JUST YET!

AS FOR STORM POTENTIAL...ACTIVITY OVER WI HAS BEEN ELEVATED...WITH 
THE ATMO STILL CAPPED WITH RESPECT TO SFC BASED CONVECTION PER THE 
STABLE CU FIELD /AT 230 PM/ STILL IN PLACE OVER WHAT IS A VERY JUICY 
WARM SECTOR...WHERE DEWPS HAVE BEEN COMMONLY RISEN UP INTO THE MID 
70S. STILL LOTS OF DISAGREEMENT WITH WHETHER OR NOT THIS FRONT WILL 
EVEN GENERATE CONVECTION...BUT GIVEN THE DEGREE OF INSTABILITY 
PRESENT...ALONG WITH THE SHORTWAVE MOVING INTO WRN MN AS EVIDENCED 
BY DRYING ON WATER VAPOR BACK ACROSS THE DAKOTAS...PREFER THE IDEA 
THE HRRR AND MEMBER1 OF THE 15Z HOPWRF SHOW WITH A SCT LINE OF 
STORMS DEVELOPING ALONG THE FRONT AROUND 20Z AND QUICKLY SPREADING 
EAST. THIS WOULD PLACE THE THUNDER THREAT MAINLY ALONG AND EAST OF 
AN ALBERT LEA TO RICE LAKE LINE. SFC WINDS HAVE VEERED CONSIDERABLY 
DURING THE DAY...WHICH WILL RESULT IN A MINIMAL TORNADO THREAT...BUT 
2K-4K J/KG OF MLCAPE...H7-H5 LAPSE RATES UP OVER 7 DEG C/KM...AND 
EFFECTIVE SHEAR AROUND 40 KTS WILL BE MORE THAN ENOUGH TO SUPPORT A 
WIND/HAIL THREAT...ESPECIALLY TOWARD THE IOWA BORDER WHERE 
INSTABILITY AND LAPSE RATES ARE BETTER.

WILL SEE SKIES CLEAR OUT TONIGHT...BUT CONSISTENT NW WINDS WILL 
BRING IN DEWPS IN THE LOWER/MID 60S...WHICH WILL LIMIT THE FOG 
POTENTIAL. IN ADDITION...A VERY POTENT SHORTWAVE CURRENTLY OVER NRN 
SASKATCHEWAN WILL DROP INTO NODAK TONIGHT...WITH ACTIVITY EXPECTED 
TO DEVELOP OVER CENTRAL NODAK THIS EVENING. THIS WILL LIKELY SEND 
SHOWERS/STORMS TOWARD CENTRAL MN LATE TONIGHT INTO MONDAY 
MORNING...THOUGH MORE ROBUST STORM COVERAGE OVER THE MPX CWA IS NOT 
EXPECTED UNTIL MONDAY AFTERNOON AS THAT STRONG SASKATCHEWAN WAVE 
MOVES INTO WRN MN. FOR THIS WAVE...PREFERRED A GEM/ECMWF/GFS BLEND 
FOR ITS TIMING. THE NAM IS ABOUT 6 HOURS FASTER WITH THE 
WAVE...PLACING IT OVER ERN MN BY THE END OF THE SHORT TERM AS 
OPPOSED TO WRN MN AS THE OTHER GUIDANCE SHOWS. DETERMINISTIC MODELS 
SHOW FAIRLY WIDESPREAD CONVECTION DEVELOPING BASED ON THEIR QPF 
FIELDS...BUT THE CAMS SHOW ACTIVITY BEING NOTICEABLY MORE SCATTERED 
OVER MN MONDAY AFTERNOON. THIS IS LIKELY DUE TO THE FACT THAT THERE 
REALLY IS NO STRONG SFC FEATURE TO FOCUS ACTIVITY DURING THE 
AFTERNOON...SO THE CAMS ARE SIMPLY GENERATING CONVECTION WHERE THEY 
CAN DEVELOP ENOUGH INSTABILITY.

THOUGH NW FLOW IS EXPECTED...1.5-2.5K J/KG OF MLCAPE COMBINED WITH 
50-60 KTS OF BULK SHEAR WILL BE MORE THAN ENOUGH TO SUPPORT A SEVERE 
THREAT. HODOGRAPHS FOR MONDAY ARE MOSTLY LONG STRAIGHT 
LINES...INDICATING THE MAIN THREAT WOULD BE LARGE HAIL FROM 
SPLITTING SUPERCELLS. IF ENOUGH STORMS CAN INITIATE...WE WOULD 
LIKELY END UP WITH A COMPLEX OF STORMS OR TWO THAT WOULD HAVE A WIND 
TREAT AS WELL. HIGHER LCLS /DUE TO THE DRIER BOUNDARY LAYER AIR 
EXPECTED/ ALONG WITH THE SHEAR BEING MAINLY OF THE SPEED VARIETY 
/WITH LITTLE DIRECTION CHANGE/ WILL GREATLY LIMIT ANY TORNADO 
THREAT.

.LONG TERM...(MONDAY NIGHT THROUGH SUNDAY)
ISSUED AT 328 PM CDT SUN JUL 6 2014

WHILE THE BEST STORM COVERAGE SHOULD GENERALLY BE BETWEEN 21-00Z
IN WESTERN MN...EASTERN MN WILL HAVE THE BEST SHOT AT THUNDER
BETWEEN 00-03Z...AND SHORTLY THEREAFTER IN WESTERN WI. THE MID-
LEVEL DRYING ARRIVES QUICKLY BETWEEN 03-06Z IN THE EASTERN
FORECAST AREA...SO THE PRECIP SHOULD GET QUICKLY SHUFFLED OFF TO
THE EAST LATE TOMORROW EVENING. 

DRIER AND SLIGHTLY COOLER AIR ARRIVES BEHIND THE STORM SYSTEM ON 
TUESDAY WITH SURFACE HIGH PRESSURE EXPANDING INTO THE PLAINS AND 
UPPER LEVEL NORTHWEST FLOW. NORTHWEST WINDS WILL BE A LITTLE 
BREEZY...OTHERWISE EXPECT MOSTLY SUNNY SKIES AND MILD TEMPERATURES 
IN THE 70S TO NEAR 80 DEGREES. UPPER LEVEL RIDGING FLATTENS AS IT
SHIFTS INTO THE HIGH PLAINS ON WEDNESDAY...HOWEVER WITH RETURN
FLOW DEVELOPING IN WESTERN MN IN THE AFTERNOON HIGH TEMPERATURES
WILL IMPROVE A FEW DEGREES. THE EAST WILL REMAIN ON THE FRINGE OF
AN 850MN COLD POCKET CENTERED ROUGHLY OVER LAKE SUPERIOR. MID AND
HIGH CLOUDS BUILDING INTO THE AREA FROM THE WEST. MODEL
CONSISTENCY ISN'T AS GOOD LATER IN THE WEEK WITH WEST TO NORTHWEST
UPPER FLOW AND THE POSSIBILITY OF A FEW WEAK WAVES TO TRACK
THROUGH THE AREA. THE TIMING OF THESE WAVES REMAIN TOO DIFFICULT
TO PINPOINT WITH EACH MODEL SHOWING SLIGHTLY DIFFERENT
TIMING AND LATITUDINAL PLACEMENT - DID NOT REALLY ALTER THE POPS
MUCH WEDNESDAY NIGHT AND BEYOND. TEMPERATURES ARE EXPECTED TO
REMAIN WITHIN A FEW DEGREES OF CLIMATE NORMALS DURING THE PERIOD.
AFTER MONDAY...THE NEXT SUBSTANTIAL PROBABILITY FOR PRECIP ARRIVES
ON THURSDAY WHEN THE FLOW BECOMES A LITTLE MORE W-SW AND WARM
ADVECTION ARRIVES FROM THE DAKOTAS.

&&

.AVIATION...(FOR THE 06Z TAFS THROUGH 06Z MONDAY NIGHT)
ISSUED AT 1155 PM CDT SUN JUL 6 2014

VFR CONDITIONS EXPECTED MOSTLY THROUGH THE PERIOD WITH BOUTS OF
DETERIORATING CONDITIONS POSSIBLE WITH SHOWER/THUNDERSTORM ACTIVITY
MONDAY AND MONDAY NIGHT. SKC IS FORECAST THROUGH MOST OF TONIGHT
WITH INCREASING CLOUDS LATE. A LEADING DISTURBANCE MAY BRING
SHOWERS INTO WESTERN MINNESOTA TOWARD DAWN...WITH ACTIVITY
BECOMING MORE WIDESPREAD AS THE AFTERNOON PROGRESSES. A LOT OF THE
HI RES MODELS KEEP THE TSRA SCATTERED WHICH MAKES IT DIFFICULT TO
FORECAST TIMING AT ANY GIVEN TAF LOCATION. WHILE IT IS LIKELY ALL
TAF SITES WILL EXPERIENCE THIS ACTIVITY AT SOME POINT MONDAY INTO
MONDAY EVENING...CONFIDENCE IS QUITE LOW ON MORE PRECISE DETAILS
AT THIS TIME.

KMSP...VFR CONDITIONS THROUGH THE PERIOD WITH THE POSSIBILITY OF
BRIEF INSTANCES OF IFR OR MVFR CONDITIONS IN SHRA/TSRA. KEPT MOST
OF THE PERIOD DRY UNTIL CONFIDENCE IN TIMING INCREASES.

/OUTLOOK FOR KMSP/
TUE...VFR. WIND NW 10 TO 20 KT. 
WED...VFR. WIND NW 5 TO 15 KT. 
THU...VFR. CHC TSRA OVERNIGHT. WIND S 10 TO 15 KT.

&&

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

$$

SHORT TERM...MPG
LONG TERM...CLF
AVIATION...BORGHOFF