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000
FXUS63 KMPX 180848
AFDMPX

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE TWIN CITIES/CHANHASSEN MN
348 AM CDT SAT MAY 18 2013

.SHORT TERM...(THIS EVENING THROUGH SATURDAY)

TODAY-TONIGHT...BROAD-SCALE RIDGE AXIS JUST E OF THE AREA THIS
MRNG...AND WILL CONTINUE TO SHIFT E WHILE A LARGE BROAD-SCALE TROUGH
SHIFTS E THROUGH THE 4-CORNERS REGION. THOUGH OVERALL RIDGING HAS
SHIFTED E...MINOR BUBBLE RIDGES WITHIN THE DEVELOPING SW FLOW WILL
PREVENT FAIRLY WIDESPREAD PRECIPITATION FROM DEVELOPING DURG THE DAY
TDA. HOWEVER...THAT DOES NOT RULE OUT ISOLD TO SCATTERED CONVECTION
FROM THIS MRNG THROUGH THE DAY TDA. HAVE ALREADY SEEN A HANDFUL OF
SEVERE TSTM WRNGS...INCLUDING SOME VERIFYING WITH HAIL AS LARGE AS
1.5 INCHES. STORM INTENSITY WILL GENERALLY STAY ON THE TAME SIDE OF
SEVERE THRU MUCH OF THE DAY TDA WHILE CONDITIONS RAMP UP FOR THE
POTENTIAL FOR ISOLD SEVERE TSTMS LATER THIS EVE AND TNGT. ONE LOW
PRES CENTER IDENTIFIED OVER THE WRN DAKOTAS THIS MRNG WILL WORK IN
TANDEM WITH ANOTHER LOW PRES CENTER OVER WRN NE/KS. AS THE NRN LOW
SHIFTS NE...IT WILL HELP DRAG A WMFNT NE THRU SRN AND CENTRAL MN.
THIS WILL NOT ONLY ALLOW A SURGE OF WARM AIR INTO LOWER MN...PUSHING
HIGH TEMPS INTO THE LOW-MID 80S...BUT ALSO MAINTAIN DEWPOINTS INTO
THE 60S. THEN...AS THE UPPER RIDGE SHIFTS FURTHER TO THE E...MORE
PRONOUNCED MERIDIONAL FLOW WITH LOWERING HEIGHTS WILL ENHANCE LIFT.
STEEP LAPSE RATES ALONG WITH A TONGUE OF MUCH HIGHER INSTABILITY
WILL SURGE INTO WRN MN TNGT...HELPING ENHANCE THE COVERAGE AND
INTENSITY OF TSTMS TNGT. SPC MAINTAINS A SLGT RISK OF SEVERE TSTMS
IN ITS SWODY1...BUT THE TIMING IS STILL A LITTLE UNCERTAIN.
HOWEVER...LOOKING AT THE EVOLUTION OF THE TROUGH AND THE MAINTENANCE
OF RIDGING THRU THE FIRST HALF OF THE DAY...WILL HIGHLIGHT THIS EVE
THRU TNGT AS THE PERIOD WHERE SEVERE TSTMS LOOK TO OCCUR. MAIN
HAZARDS WOULD BE LARGE HAIL AND DMGG WINDS...WITH ISOLD TORNADOES AS
A SECONDARY HAZARD SINCE CONDS ARE LESS FAVORABLE FOR TORNADOES.

.LONG TERM...(SUNDAY THROUGH FRIDAY)

THE MORE SIGNFICANT THREAT FOR SEVERE WEATHER AFFECTS THE REGION
SUNDAY AND SUNDAY NIGHT. SOUTHERLY FLOW WILL BE IN PLACE ACROSS THE
AREA AS THE UPPER LEVEL TROUGH DIGS INTO THE SOUTHERN AND CENTRAL
PLAINS. THE SURFACE CYCLONE IS FORECAST TO DEEPEN AS IT MOVES
TOWARD NORTHEAST NEBRASKA BY SUNDAY EVENING. WILL LIKELY SEE
ACTIVITY WANE FROM THE SATURDAY NIGHT CONVECTION OVER THE CWA INTO
SUNDAY MORNING. WITH THE UNSTABLE AIRMASS IN PLACE..REDEVELOPMENT MAY
OCCUR QUICKLY DURING THE DAY. THE FOCUS SHOULD SHIFT WEST AGAIN IN
THE AFTERNOON ALONG THE MAIN SURFACE BOUNDARY NEARER THE NEBRASKA
LOW. A MORE SIGNIFICANT WAVE LIFTS NORTHEAST SUNDAY NIGHT AS THE
UPPER LOW PIVOTS SLOWLY EAST. FORECAST SOUNDING FOR MSP INDICATES
AROUND 2000 J/KG CAPE WITH STEEP MID LEVEL LAPSE RATES 7.5-8 C/KM.
0-6 KM SHEAR VALUES INCREASE TO 35 TO 45 KTS DURING THE EVENING AS
THE WAVE ROTATES NORTHEAST. HAIL AND DAMAGING WINDS WILL BE THE
MAIN THREATS...BUT WILL HAVE TO MONITOR LOCATION OF SURFACE FRONT
AND OCCLUDING LOW LATER INTO THE EVENING FOR ANY POSSIBLE TORNADO
THREAT. MCS DEVELOPMENT WILL LIKELY OCCUR INTO SOUTHERN MN...WITH
HEAVY RAIN ALSO POSSIBLE AS PWAT IS FORECAST TO EXCEED 1.6 INCHES.

THE OCCLUDED SYSTEM IS FORECAST TO SAG SLOWLY TO THE SOUTHEAST
MONDAY INTO TUESDAY. WILL LIKELY STILL MAINTAIN A THUNDER THREAT
THROUGH THIS PERIOD. COULD SEE SOME STRONG STORMS YET IN THE
EASTERN CWA (MAINLY WISCONSIN) FOR MONDAY AFTERNOON. THIS WILL ALL
DEPEND ON HOW MUCH DAYTIME HEATING AND DESTABILIZATION CAN TAKE
PLACE. AGAIN HEAVY RAIN WILL BE POSSIBLE...WITH WIDESPREAD 1 TO 2
INCHES FORECASTED FROM SUNDAY THROUGH MONDAY NIGHT.

TEMPERATURES WILL COOL BACK TO BELOW NORMAL READINGS TUESDAY
THROUGH THURSDAY...WITH EXTENSIVE CLOUD COVER REMAINING IN THE
AREA. WARMER AND DRIER CONDITIONS SHOULD FOLLOW THEREAFTER AS THE
UPPER LOW EXITS THE AREA.  UPPER LEVEL HEIGHTS/RIDGING ALOFT
DEVELOPS AND THIS SHOULD EXTEND INTO AT LEAST THE FIRST HALF OF
NEXT WEEKEND.

&&

.AVIATION...(FOR THE 06Z TAFS THROUGH 06Z SATURDAY NIGHT)
ISSUED AT 1202 AM CDT SAT MAY 18 2013

NO MAJOR CHANGE FROM THE 00Z TAF...TRIED TO TIME IN THE
THUNDERSTORMS CURRENTLY IN SD EARLY THIS MORNING. OVERALL...LOOKS
AGAIN LIKE A RAIN FILLED DAY WITH A COUPLE ROUNDS OF SHOWERS AND
STORMS SEPARATED BY LONG BREAK IN BETWEEN. THE FIRST ROUND ARRIVES
THIS MORNING AND THE SECOND THIS EVENING.

KMSP...

MIGHT SEE THE CEILINGS AND VISIBILITY GET WORSE FOR A FEW HOURS EARLY
THIS MORNING BEFORE THE SHOWERS AND THUNDERSTORMS ROLL ACROSS THE
AREA. TRIED TO TIME IN THE EXPECTED RAIN AS BEST AS POSSIBLE AND
ACCOUNT FOR THE LONG BREAK IN BETWEEN. WE THINK MOST OF THE
THUNDERSTORM ACTIVITY WILL PASS NORTH OF THE AIRPORT THIS
MORNING...BUT ARE CLOSE ENOUGH GIVEN THE CURRENT TRENDS TO KEEP IN
THE FORECAST.

/OUTLOOK FOR KMSP/

SUN...VFR/MVFR CIGS. CHC SHRA/TSRA WITH IFR. S-SE WINDS 8-12 KTS.
MON...VFR/MVFR CIGS. CHC SHRA/TSRA WITH IFR. S WIND 10-15 KTS.
TUE...VFR/MVFR CIGS. CHC SHRA/TSRA WITH IFR. E-NE WIND 5 KTS.


&&

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

$$

SHORT TERM...JLT
LONG TERM...DWE
AVIATION...CLF