000
FXUS63 KMPX 250009
AFDMPX

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE TWIN CITIES/CHANHASSEN MN
709 PM CDT FRI MAY 24 2013

.SHORT TERM...(THIS EVENING THROUGH SATURDAY)
ISSUED AT 355 PM CDT FRI MAY 24 2013

SURFACE CYCLONE AND ASSOCIATED TROUGH NOTED ON IR SATELLITE IMAGERY
FROM SOUTHERN ALBERTA INTO EASTERN WYOMING. WARM FRONT ASSOCIATED
WITH THIS SYSTEM CURRENTLY FIRING UP SHIELD OF MAINLY LIGHT
SHOWERS AND ISOLATED THUNDERSTORMS OVER FAR EASTERN SODAK AND
WESTERN QUARTER OF OUR CWA. USED A COMBO OF HRRR...GFS40 305K
ISENTROPIC ANAL...AND THETA E ADVECTION TO PAINT PICTURE OF
FORWARD PROGRESSION ACROSS REMAINDER OF CWA DURING THE OVERNIGHT.
FAIRLY DRY COLUMN TO CONTEND WITH OVER MUCH OF THE FA THIS
AFTERNOON AND EVENING...THUS AM EXPECTING MAINLY LIGHT PCPN FOR
THIS FIRST WAVE OF ACTIVITY. ALTHOUGH K INDICES AND 850 LI`S
INDICATING LITTLE CHANCE OF THUNDER ATTM...DECIDED TO INCLUDE
ISOLATED CHANCE MOST AREAS INTO TOMORROW AFTN DUE TO FAIR AMOUNT
OF LIGHTNING NOTED ON CURRENT 0.5 REFLECTIVITY. AS PREVIOUSLY
ADVERTISED CHANCES FOR WIDESPREAD CONVECTIVE ACTIVITY DECREASE
MARKEDLY AFTER ABOUT 25/15Z TIME FRAME...AS WARM FRONTAL BOUNDARY
STALLS OVER NE MINNESOTA BY LATE SATURDAY MORNING. DECIDED TO
INCREASE SATURDAY`S HIGHS BY ONE CATEGORY CONSIDERING LIMITED PCPN
POTENTIAL AND POSSIBILITY OF MUCH LESS CLOUD COVER THEN CURRENTLY
FORECAST. FOCUS FOR ANY CONVECTIVE ACTIVITY ON SATURDAY AFTERNOON
DEFINITELY NOTED OVER FAR SOUTHERN MINNESOTA...WITH BEST UPPER
LEVEL SUPPORT VIA 250MB WEAK TO MODERATE DIVERGENCE OVER THIS
REGION. LEFT SLGT POPS OVER REMAINDER OF CWA TOMORROW AFTN DUE TO
FAIRLY ROBUST 850-500MB LAPSE RATES.

.LONG TERM...(SATURDAY NIGHT THROUGH FRIDAY)
ISSUED AT 355 PM CDT FRI MAY 24 2013

THETA E ADVECTION BLOSSOMS FROM SOUTHWEST INTO CENTRAL MN ON
SATURDAY NIGHT INTO SUNDAY...WHEN BOTH GFS AND NAM MODELS FORECAST A
SHORTWAVE TO CARVE THROUGH THE MID LEVEL RIDGE. EXPECT TO SEE
SCATTERED SHOWERS AND THUNDERSTORMS DEVELOPING...WITH THE HIGHEST
COVERAGE OVER SOUTHWEST MN WHERE 850 MB MOISTURE TRANSPORT IS
SLIGHTLY ENHANCED. HIGH TEMPERATURES ON SUNDAY WILL LIKELY MAX
OUT IN THE UPPER 50S AND LOWER 60S...AS THE WARM FRONT REMAINS TO
THE SOUTH OF THE AREA AND EXTENSIVE CLOUD COVER AND SHOWERS
PERSIST.

YET MORE WEAK SHORTWAVES RIDE NORTH OF THE WARM FRONT ON MEMORIAL
DAY...AND CONTINUE THE POSSIBILITY OF SCATTERED SHOWERS AND
THUNDERSTORMS. SHOULD SEE TEMPS MODERATE SLIGHTLY FOR THE
HOLIDAY...ALTHOUGH IT WILL STILL BE ON THE COOL SIDE WITH UPPER
60S TO MID 70S.

ON TUESDAY...THE AFOREMENTIONED WARM FRONT WILL BEGIN TO LIFT
NORTH...AND ENTER THE FORECAST AREA FROM WEDNESDAY THROUGH
THURSDAY. THIS WILL SIGNAL THE ARRIVAL OF SLIGHTLY WARMER
TEMPERATURES AND AN INCREASE IN HUMIDITY...WITH HIGHS IN THE 75 TO
80 DEGREE RANGE. THE ARRIVAL OF THE FRONT WILL ALSO YIELD AN
INCREASING THREAT FOR SEVERE WEATHER AND EXCESSIVE RAINFALL FOR
THURSDAY AND FRIDAY. FORECAST PRECIPITABLE WATER VALUES INCREASE TO
OVER 1.5 INCHES...WHICH ILLUSTRATES THE POTENTIAL FOR A DOUSING
RAINFALL EVENT. THE SEVERE WEATHER POTENTIAL IS SOMEWHAT UNCERTAIN
DUE TO THE DIFFERENCES IN THE MODELS WITH THE EVOLUTION OF THE
WESTERN TROUGH...AND THE DEGREE OF SURFACE CYCLOGENESIS THAT
ENSUES OVER THE NORTHERN PLAINS TOWARD THE END OF NEXT WEEK.
HOWEVER...IF THE 24.12Z GFS SHEAR AND INSTABILITY PROGS WERE TO
PAN OUT...THERE WOULD BE A FAIRLY HIGH THREAT FOR SEVERE WEATHER
AND TORNADOES ACROSS CENTRAL AND SOUTHERN MN ON THURSDAY
AFTERNOON/EVE. WILL CONTINUE TO MONITOR AND REFINE OVER THE NEXT
FEW MODEL RUNS.

&&

.AVIATION...(FOR THE 00Z TAFS THROUGH 00Z SATURDAY EVENING)
ISSUED AT 648 PM CDT FRI MAY 24 2013

SOME WIDELY SCATTERED MVFR CIGS ASSOCIATED WITH THUNDER OVER
WESTERN MN THIS EVENING. SHOULD WEAKEN/AT LEAST LOSE MORE OF THE
THUNDER AS IT RIDES EAST HIS EVENING. WILL MENTION SOME TEMPO
THUNDER AT KRWF THIS EVENING. THEN JUST SHRA INDICATED MOST AREAS
DURING THE NIGHT INTO SATURDAY. BEST SHOT OF MVFR WEST OVERNIGHT...
COULD SPREAD EAST INTO EASTERN MN BY 12Z SAT. EXPECT MVFR CIGS
INTO THE DAY MOST AREAS AHEAD OF DEVELOPING LOW PRESSURE AND WARM
FRONT TO THE WEST AND SOUTH OF THE AREA. SOUTHEAST OR BECOMING
SOUTHEAST WINDS TONIGHT INCREASING INTO SATURDAY AS PRESSURE
GRADIENT INCREASES.

KMSP...
SHRA MOVING THROUGH THE AREA DURING THE EVENING. SHOULD BE MORE
SCATTERED AFTER 06Z. LIMITED THREAT OF ANY THUNDER MAINLY WEST AND
SOUTH OF THE FILED OVERNIGHT. MVFR CIGS COULD DEVELOP LATE TONIGHT
AS LOWER LEVELS SATURATE MORE. THIS WILL LINGER INTO THE DAYLIGHT
HOURS OF SATURDAY AS WELL. SOME THREAT OF SHRA INTO THE AFTERNOON
OR SATURDAY EVENING...BUT LOOKS RATHER LOW AT THIS TIME.  DECIDED
TO LEAVE THAT OUT FOR NOW. WIND SHOULD BE SOUTHEAST MOST OF THE
PERIOD AND INCREASE SATURDAY AHEAD OF DEVELOPING LOW PRESSURE OVER
THE DAKOTAS AND WARM FRONT OVER IOWA.


/OUTLOOK FOR KMSP/
SAT NIGHT...CHC MVFR OR LOWER CIGS. CHC SHRA/TSRA. WINDS SE 10-15 KTS.
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.

&&

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

$$

SHORT TERM...AJZ
LONG TERM...LS
AVIATION...DE