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000
FXUS63 KMPX 051213
AFDMPX

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE TWIN CITIES/CHANHASSEN MN
613 AM CST WED MAR 5 2014

.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 406 AM CST WED MAR 5 2014

QUITE THE SNOWFALL EVENT LAST NIGHT FOR A NARROW AREA ACROSS
SOUTHERN MINNESOTA...AS A NARROW BAND OF HEAVY SNOW SETUP ACROSS
THIS AREA AND DROPPED 6 TO 11 INCHES OF NEW SNOW ACROSS ABOUT A 20
MILE WIDE SWATH FROM NEAR ST. JAMES...THROUGH
MAPLETON...MADELIA...NEW RICHLAND...AND ALBERT LEA. THE RAP
ANALYZED 600-700H FGEN WAS VERY IMPRESSIVE AND THIS BAND SETUP ON
THE SOUTHERN PERIPHERY OF THE HIGHEST FGEN...OR IN OTHER
WORDS...ALONG THE FGEN GRADIENT AT THIS LEVEL. NEGATIVE EPV ALSO
INDICATED THE POSSIBILITY OF CONDITIONAL SYMMETRIC INSTABILITY
WHICH CERTAINLY MAKES SENSE GIVEN THE INTENSITY OF THIS MESOSCALE
BAND OF SNOW. OTHER THAN THIS BAND...2-5" WAS COMMON IN AREAS
LUCKY ENOUGH TO AVOID THE HEAVY BAND.

EARLY THIS MORNING...THE SNOW WAS QUICKLY DIMINISHING AND ADVECTING
EAST OF THE FA...WITH LIGHT SNOW STILL BEING REPORTED IN SOUTHEAST
MN. ONCE THIS LIGHT SNOW MOVES ON OVER THE NEXT FEW HOURS...NO
ADDITIONAL POPS ARE IN THE SHORT TERM FORECAST PERIOD.  PREVIOUS
FORECAST INCLUDED SLIGHT CHANCE POPS THROUGH NORTH CENTRAL MN...BUT
HI RES MODELS INDICATE ANY PRECIPITATION WITH THIS NEXT WAVE
TONIGHT WILL STAY NORTH OF THE FA.

WARM AIR ADVECTION PICKS UP TONIGHT AS SOUTHERLY WINDS PICK UP
THROUGH THE NIGHT. CLOUD COVER HAS PROVED TO BE A CHALLENGE...GOING
WITH A LOW CONFIDENCE FORECAST GIVEN MODEL DISAGREEMENT IN HANDLING
LOW LEVEL MOISTURE.  CURRENT THINKING IS THAT CLOUD COVER THIS
MORNING IS OVERBLOWN BY THE RAP. THE NAM INDICATES A DECREASING
TREND...BUT NOT ENOUGH IMO. HOPWRF PROBS PREFERRED FOR CIGS...WHICH
IS NOT SO PESSIMISTIC ABOUT LOW STRATUS DEVELOPMENT.

.LONG TERM...(THURSDAY THROUGH TUESDAY)
ISSUED AT 406 AM CST WED MAR 5 2014

FOR THIS PERIOD...MODELS ARE SHOWING A FAIRLY PROGRESSIVE PATTERN
SETTING UP...WITH THE PREDOMINATE AIRMASS TYPE BEING THAT OF THE
MILDER PACIFIC ORIGIN. MODEL AGREEMENT REMAINS PRETTY HIGH THROUGH
THE WEEKEND...THOUGH BEGINS TO DIVERGE BY THE BEGINNING OF NEXT
WEEK. PRECIPITATION WISE...IT LOOKS ON THE WHOLE TO BE DRY...WHICH
MEANS FOR THE FIRST TIME SINCE WE GOT OUR SNOWPACK IN EARLY
DECEMBER...WE LOOK TO HAVE A WEEK OF WEATHER WHERE WE ACTUALLY LOSE
SOME OF OUR HEFTY SNOWPACK AS OPPOSED TO CONTINUALLY ADD ON TO IT.

BIGGEST CONCERN WEATHER WISE IN THE LONG TERM COMES IN PRETTY MUCH
RIGHT OF THE GATE WITH THE COLD FROPA PASSAGE THU NIGHT INTO FRIDAY
MORNING. THE BIGGEST CHANGE NOTED WITH THE FRONT IN THE 05.00 MODEL
RUNS IS A SLIGHT SLOWING IN ITS PROGRESS ACROSS THE MPX AREA. WHAT
HAS NOT CHANGE IS LACK OF DEEP MOISTURE TO WORK WITH AS THIS FRONT
COMES THROUGH. FOR THURSDAY...HAVE REMOVED ANY POPS...WITH WAA
PRECIP LOOKING TO REMAIN WELL NORTH OF THE MPX AREA. ALSO BOOSTED
MAX TEMPS A FEW DEGREES OUT WEST...WHERE STRONG S/SW WINDS WILL
DEVELOP...WITH HIGHS AROUND 40 LOOKING LIKELY DOWNWIND OF THE
BUFFALO RIDGE. FOR ERN MN/WRN WI...THE BIG QUESTION MARK FOR HIGHS
ON THURSDAY IS HOW LONG DO THE WINDS REMAIN SE. THE 05.00 ECMWF
NEVER REALLY TAKES WINDS WEST OF SOUTH ON THURSDAY IN THE EAST...AND
IF THIS HAPPENS...WILL MAKE IT TOUGH FOR ERN MN AND WRN WI TO GET
OUT OF THE 20S. WHAT DOES LOOK MORE CERTAIN IS THAT THE SLOWER
MOVEMENT OF THE FRONT THURSDAY NIGHT WILL RESULT IN A VERY MILD
EVENING FOR THE ENTIRE CWA...WITH LOWS IN THE MID/UPPER 20S.

AS FOR PRECIP POTENTIAL WITH THE FRONT...DEEP MOISTURE STILL LOOKS
TO BE A LIMITING FACTOR. THE ECMWF CONTINUES TO SHOW THE FRONT
COMING TROUGH DRY...BUT THE 05.00 GFS/GEM ALONG WITH THE SREF WITH
ITS 05.03 RUN SHOW THE ATMOSPHERE MOISTENING ENOUGH ALONG THE FRONT
TO GET A LITTLE BIT OF PRECIP GOING. HAVE CHANE POPS WORKING ACROSS
THE AREA MAINLY 6Z TO 18Z FRIDAY FOLLOWING A BLEND OF THE
SREF/GEM/GFS. P-TYPE LOOKS TO BE AN ISSUE AS WELL WITH ANYTHING
FALLING OUT AHEAD OF THE FRONT COMING IN THE LIQUID FORM /DZ OR
RA/...WHICH WOULD BE OF THE FREEZING FORM GIVEN TEMPERATURES
EXPECTED AROUND 30. DO NOT THINK MUCH SNOW WILL BE SEEN AS THOSE
COLDER TEMPERATURES WILL ALSO BE COMING WITH DRIER AIR THAT SHOULD
SHUT OFF THE PRECIP BEFORE MUCH IN THE WAY OF SNOW FALLS.

IN THE WAKE OF THE FRONT...WILL SEE BREEZY NW WINDS AND GOOD
CAA...WITH TEMPS DURING THE DAY FRIDAY LIKELY FALLING THROUGH THE
DAY. THE POLAR HIGH GIVING US THESE COLDER TEMPERATURES WILL KEEP US
COOL THROUGH SATURDAY AS IT SLOWLY WORKS FROM THE DAKOTAS INTO THE
MID MISSISSIPPI VALLEY. HOWEVER...AS IT IS DOING THIS AT THE
SFC...ALOFT...AN H5 RIDGE WILL BE COMING OUT OF THE ROCKIES AND ON
TO THE PLAINS WHICH WILL SET US UP FOR SOME THE WARMEST AIR WE HAVE
SEEN SINCE NOVEMBER AS H85 TEMPS CLIMB TO AROUND +10C. THIS WILL
GIVE EVERYONE A GOOD SHOT AT CRACKING 40 SUNDAY AND ESPECIALLY
MONDAY...WITH LOWS MONDAY POSSIBLY EVEN STAYING ABOVE FREEZING FOR
SW MN. IF ANYTHING...CURRENT GRIDS FOR HIGHS BOTH DAYS ARE LIKELY
UNDERDONE.

&&

.AVIATION...(FOR THE 12Z TAFS THROUGH 12Z THURSDAY MORNING)
ISSUED AT 611 AM CST WED MAR 5 2014

INITIALLY EXPECT VFR CIGS ACROSS THE TAF SITES ALONG WITH EAST OR
NORTHEAST WINDS.  THE MAIN AVIATION IMPACTS THIS PERIOD WILL BE THE
FORECAST FOR MVFR CIGS TO OVERTAKE THE AREA THIS AFTERNOON... AND
TIMING OF THE WIND SHIFTING SOUTHERLY TODAY. RIGHT AWAY THIS MORNING
WE HAVE PLENTY OF CLEAR SKIES WITH A FEW MID/HIGH LEVEL CLOUDS
ACROSS THE CWA...WITH ROUGHLY 5K FT DECK ENCROACHING ON THE
MINNESOTA BORDER WITH BOTH OF THE DAKOTA STATES.  THE WAVE TO THE
SOUTHEAST HAS LEFT SOME LINGERING LOWER CLOUD COVER IN FAR SOUTHERN
MINNESOTA...BUT EXPECT THAT TO NOT IMPACT ANY TAF SITES THIS
MORNING.  WINDS BEGIN TURING SOUTHERLY THIS AFTERNOON AS WAA
INCREASES AS THE DOES LOW LEVEL SATURATION ACROSS THE AREA.
PREFERRED MODEL SOUNDINGS INDICATE MVFR IS A DECENT LIKELIHOOD THIS
AFTERNOON. CONFIDENCE IN THIS DEVELOPMENT IS BELOW NORMAL...AS SOME
DIFFERENCES IN SATURATION EXIST IN THE MODELS. WINDS INCREASE FURTHER
TONIGHT AND BECOME GUSTY OVERNIGHT.

KMSP...MVFR CIGS EXPECTED TO DEVELOP THIS AFTERNOON. WINDS WILL TURN
TOWARD THE SOUTHEAST THROUGH THE DAY...AND EVENTUALLY SOUTHERLY
TONIGHT AS SPEEDS INCREASE.  EXPECTING VFR TO RETURN AFTER MIDNIGHT
AS DRIER SOUTHWEST FLOW SCOURS OUT THE LOW LEVEL MOISTURE.

KMSP...

/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...NONE.
WI...NONE.
&&

$$

SHORT TERM...SPD
LONG TERM...MPG
AVIATION...SPD