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000
FXUS63 KMPX 050018
AFDMPX

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE TWIN CITIES/CHANHASSEN MN
618 PM CST TUE MAR 4 2014

.SHORT TERM...(THIS EVENING AND TONIGHT)
ISSUED AT 112 PM CST TUE MAR 4 2014

SEVERAL FACTORS HAVE SLOWLY COME TOGETHER THIS AFTN FOR A QUICK 2
TO 4 INCH SNOWFALL ACROSS FAR SOUTHERN MN DUE TO THE COMBINATION
OF A STRONG SHRTWV & WAA LAYER /92-70H/ MOVING THRU SOUTHERN MN
THIS EVENING.

ALTHOUGH REGIONAL RADAR WAS DEPICTING A LARGE AREA OF HIGHER
RETURNS ACROSS SD/ND MOVING SE EARLY THIS AFTN...THE CONTINUED DRY
FLOW FROM THE GREAT LAKES WILL KEEP MOST OF THE ACCUMULATING
SNOWFALL SOUTH OF I-94. IT MAY EVEN TAKE A FEW HRS BEFORE THE
ATMOSPHERE SATURATES ENOUGH FOR THE SNOW TO REACH THE GROUND IN EC
MN. OVER THE PAST FEW RUNS OF THE HOPWRF AND RAP...THERE REMAINS A
VERY SHARP BOUNDARY BETWEEN NO SNOWFALL...AND LOCALLY 1 TO 2
INCHES ALONG THE I-94 CORRIDOR. TRENDS HAVE BEEN FOR THE DRIER AIR
TO HOLD THE NE 1/3 OF MPX CWA DRY...WITH THE BULK OF THE QPF SOUTH
OF NEW ULM TO OWATONNA. I DID NOT WANT TO GET TOO SPECIFIC ON
WHERE THE CUTOFF WOULD BE TO THE NE...BUT IT IS LIKELY THAT THE
NORTHERN PART OF THE TWIN CITIES MAY ONLY GET FLURRIES...WITH ONE
TO TWO INCHES IN SCOTT/DAKOTA COUNTIES. AGAIN...THIS IS BASED ON
THE CURRENT RUN OF BOTH THE HOPWRF/RAP. ANY DEVIATION TO THE
STRONGER FORCING ALONG THE 92-70H FRONTOGENETIC ZONE THIS
EVENING...WILL CAUSE MORE OR LESS SNOWFALL ACROSS CENTRAL MN/WC
WI. OTHERWISE...THIS SYSTEM IS FAIRLY FAST AND WILL MOVE OUT OF
THE REGION BY 12Z.

.LONG TERM...(WEDNESDAY THROUGH TUESDAY)
ISSUED AT 336 PM CST TUE MAR 4 2014

THE WELL-ADVERTISED MODERATING TEMPERATURES STILL LOOK GOOD
THROUGH THE EXTENDED AND EVEN WITH THE MULTIPLE PERIODS OF CHANCE
POPS...THE NEXT 7 DAYS LOOKS FAIRLY DRY. THE NEXT CHANCE FOR A
+40 DAY LOOKS LIKE MONDAY WITH A STRONG SOUTHWEST FLOW AND WARM
ADVECTION THAT KICKS IN SUNDAY NIGHT. IN FACT...IT MIGHT BE 40
DEGREES AT SUNRISE MONDAY MORNING...WITH A SLIGHT COOLING TREND
DURING THE AFTERNOON WITH A COLD FRONT. THESE ARE THINGS THAT WILL
BE WORKED OUT WITH TIME. FRIDAY MORNING WILL ALSO BE QUITE MILD
AND WOULDN`T BE SURPRISED TO A NON-DIURNAL TREND THURSDAY NIGHT
AND WIDESPREAD >32 TEMPS BY SUNRISE FRIDAY MORNING. THAT BEGS THE
QUESTION WHAT KIND (IF ANY) PRECIP FALLS FROM THE SKY THURSDAY
NIGHT INTO FRIDAY MORNING. THE QPF IS LIGHT AND THE FORCING FAVORS
MOST OF THE ACTIVITY NORTH OF THE FORECAST AREA...A TREND THAT HAS
DEVELOPED OVER THE PAST 3-4 MODEL CYCLES. THE NAM GENERALLY HAS A
SNOW -> BREAK -> FREEZING RAIN -> RAIN -> SNOW TREND DURING THIS
TIME. MEANWHILE...THE GFS TREND MORE LIKE SNOW -> SLEET ->
FREEZING RAIN -> SNOW. PRETTY MESSY...ESPECIALLY WITH THE TREND
VARYING SPATIAL AND LACKING MODEL CYCLE CONSISTENCY. WE STAYED
PREDOMINATELY LIGHT SNOW...BUT ARX/DMX NWS OFFICES MIGHT HAVE THE
BETTER IDEA CHANGING OVER TO FREEZING DRIZZLE FOR A WHILE ON
FRIDAY. IT COULD JUST AS EASY BE NEARLY DRY AND SIMPLY BE
OVERCAST. LOW CONFIDENCE P-TYPE FORECAST AT THIS POINT...BUT WE
ARE CONFIDENT IN A LOW-TO-NO QPF COLD FRONTAL PASSAGE THURSDAY
NIGHT INTO FRIDAY.

&&

.AVIATION...(FOR THE 00Z TAFS THROUGH 00Z WEDNESDAY EVENING)
ISSUED AT 548 PM CST TUE MAR 4 2014

SWATH OF -SN OVER MAINLY SRN MN WILL INCREASE IN COVERAGE...ALONG
WITH POCKETS OF HIGHER INTENSITIES...THIS EVE BUT THE ENTIRE EVENT
LOOKS TO COME TO AN END BETWEEN 06Z-09Z. THE BULK OF THIS ACTIVITY
WILL OCCUR S OF THE I-94 CORRIDOR...MEANING THAT KAXN-KSTC-KRNH
LOOK TO REMAIN IMMUNE FROM ANY -SN...WHILE KMSP-KEAU WILL GET
GLANCING BLOWS...AND KRWF WILL BE SQUARELY IN THE MIDDLE OF THIS
ACTIVITY AND WILL HAVE THE BEST CHC OF DROPPING INTO IFR RANGE.
KMSP-KEAU LOOK GOOD TO DROP INTO MVFR...WITH MUCH LOWER CONFIDENCE
OF ANYTHING WORSE. ONCE THE -SN MOVES OUT...VFR-TO-MVFR CEILINGS
WILL PREVAIL THRU DAYBREAK AND THE FIRST HALF OF THE DAY WED
BEFORE CEILINGS GRADUALLY RISE INTO VFR RANGE. WINDS WILL HAVE A
PREVAILING ELY COMPONENT...SHIFTING FROM NE TO SE TNGT THRU TMRW
WITH SPEEDS MAINLY IN THE 5-10 KT RANGE...THOUGH SPEEDS MAY INCRS
TO THE 10-15 KT RANGE ARND 00Z TMRW EVE.

KMSP...WNW-ESE ORIENTED BATCH OF -SN JUST S OF KMSP LOOKS TO STAY
THERE...POSSIBLY WITH A FEW BURSTS OF MVFR-RANGE -SN HITTING KMSP
OVER THE NEXT COUPLE OF HRS. OTHERWISE...THIS EVENT LOOKS TO BE
MORE OF A NON-EVENT FOR KMSP. CEILINGS WILL GRADUALLY LOWER INTO
MVFR RANGE THIS EVE INTO THE EARLY MRNG HRS BUT CONFIDENCE IS LOW
ON CIGS DROPPING BELOW 1800 FT. WILL HOLD ON TO THE UPPER- RANGE
MVFR CEILINGS THRU LATE MRNG THEN CONDS BECOME SOLIDLY VFR TMRW
AFTN.

/OUTLOOK FOR KMSP/
THU...VFR. WINDS S 10-20 KTS.
FRI...VFR. WINDS W 5-10 KTS...BECOMING N.
SAT...VFR. WINDS N 5-10 KTS...BECOMING W.

&&

.MPX WATCHES/WARNINGS/ADVISORIES...
MN...WINTER WEATHER ADVISORY UNTIL 3 AM CST WEDNESDAY FOR MNZ074-
     082>085-091>093.

WI...NONE.
&&

$$

SHORT TERM...JLT
LONG TERM...CLF
AVIATION...JPC