000
FXUS63 KMPX 061002
AFDMPX

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE TWIN CITIES/CHANHASSEN MN
402 AM CST THU MAR 6 2014

.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 358 AM CST THU MAR 6 2014

PRIMARY CONCERNS IN THE SHORT TERM PERIOD INCLUDE BLOWING SNOW TODAY
ACROSS SOUTHERN MINNESOTA WHERE FRESH SNOW COVER EXISTS...CLOUD COVER
TODAY /AND ITS IMPACT ON HIGH TEMPS/...AND MIXED PRECIPITATION LATE
TONIGHT.

WIND SPEEDS AND GUSTS WERE CHANGED SLIGHTLY FROM THE PREVIOUS
FORECAST...MAINLY JUST TIMING DIFFERENCES...MAGNITUDES LOOK
CONSISTENT. THE QUESTION IS HOW SEVERE THE BLOWING SNOW WILL BE.
DECIDED TO HOLD OFF ON AN ADVISORY RIGHT NOW...AS CONFIDENCE IN
THE SEVERITY OF BLOWING SNOW IS HAMPERED BY THE FACT THAT THIS
WILL BE A SOUTH WARM ADVECTION WIND. IN THE PAST...SOUTHERLY WINDS
HAVE STRUGGLED TO PRODUCE SIGNIFICANT BLOWING SNOW. SO...ALONG
WITH COLLABORATION WITH NEIGHBORING OFFICES...HAVE DECIDED TO
COVER THE BLOWING SNOW IN THE GRIDDED FORECAST...AND HWO.

CLEARING TRENDS ACROSS WESTERN MINNESOTA WILL SLOWLY CONTINUE
TODAY...BUT THE QUESTION IS HOW LONG WILL THE LOW STRATUS HANG
AROUND EASTERN MINNESOTA AND INTO WESTERN WISCONSIN. RAP
CONDENSATION PRESSURE DEFICIT AT THE 0.5KM LEVEL HAS HANDLED THE
CLOUD COVER WELL OVERNIGHT...AND LEANED TOWARD ITS SOLUTION THROUGH
THE MORNING. THIS MEANS LOW STRATUS WILL TEND TO DECELERATE OVER
EASTERN MINNESOTA AND LINGER THROUGH AT LEAST MIDDAY ACROSS THE
METRO AND AREAS EAST. HAVE TRENDED TEMPERATURES SLIGHTLY COOLER
ACROSS THE EASTERN PORTION OF THE FA DUE TO LINGERING CLOUD COVER
AND ALSO DUE TO THE SSE WIND EXPECTED THROUGH THE FIRST HALF OF THE
DAY.

NEWEST MODEL DATA SUGGESTS OUR FA WILL REMAIN DRY THROUGH MIDNIGHT
TONIGHT.  A FIRST LOOK AT A FEW HIGH-RES MODELS INDICATE THE
PRECIPITATION TO REMAIN ACROSS NORTHERN MN THIS EVENING. MODEL
SOUNDINGS LACKED NEGATIVE OMEGA WITH MOISTURE...AND DRY AIR IN THE
MID LEVELS SHOWED THE DISCONNECT BETWEEN THE LOW LEVEL MOISTURE AND
UPPER LEVEL MOISTURE. A BETTER CONNECTION IS MADE AFTER MIDNIGHT
ALONG AND AHEAD OF THE INCOMING COLD FRONT. GENERALLY EXPECT VERY
LIGHT FZDZ EARLY FRIDAY MORNING WITH LITTLE OR NO ACCUMULATION AT
THIS TIME.

.LONG TERM...(FRIDAY THROUGH WEDNESDAY)
ISSUED AT 358 AM CST THU MAR 6 2014

STILL LOOKS GOOD FOR US TO GET OUR MELT ON IN THE EXTENDED...
ESPECIALLY SUNDAY AND MONDAY. IT ALSO LOOKS TO BE MAINLY DRY AS WE
STRUGGLE TO EVER PERFECTLY LINE UP FORCING AND DEEP MOISTURE WITH
ONLY SHOTS AT SOME LIGHT PRECIP LOOKING TO COME FRIDAY AND AGAIN MON
NIGHT/TUES.

THE FIRST PROBLEM AT HAND IS THE COLD FRONT THAT WILL BE STARTING
OUT FRIDAY MORNING DRAPED SW TO NE ACROSS MN. AGAIN THE PRECIP END
OF THIS FRONT LOOKS TO BE OF THE SHAKESPEAREAN NATURE...MUCH ADO
ABOUT NOTHING. LOOKING AT FORECAST SOUNDINGS...THE BOUNDARY LAYER
LOOKS TO BE PLENTY MOIST THANKS TO THE SNOW PACK MOISTURE FEED...BUT
THE PROBLEM RESIDES BETWEEN 2K AND 10KT FEET...WHICH TIME-HEIGHT RH
CROSS SECTIONS FROM THE GFS/NAM SHOW REMAINING FAIRLY DRY. IN
ADDITION TO THE MOISTURE ISSUE...WE ARE ALSO SEEING A SPLIT IN THE
FORCING...WITH THE MAIN SHORTWAVE REMAINING UP IN SRN CANADA...WHILE
A WEAKER WAVE TRACKS ACROSS THE CENTRAL PLAINS AND INTO MO/IA. TO
PILE ON THE NEGATIVES FOR GETTING MUCH PRECIP WITH THIS FRONT...LOW
LEVEL CONVERGENCE ALONG THE BOUNDARY LOOKS FAIRLY WEAK. NEEDLESS TO
SAY...SAW NO REASON OVERNIGHT TO RAISE POPS ANY HIGHER THAN THE
20S/LOW 30S THAT WERE INHERITED. FOR P-TYPE...ANYTHING THAT DOES
FALL STILL LOOKS TO COME IN MAINLY THE LIQUID VARIETY...AS THE
COLDER TEMPS THAT WOULD MAKE SLEET/SNOW LOOK TO ARRIVE WITH DRIER
AIR AND THEREFORE COINCIDE WITH THE ENDING OF PRECIP AS WELL.

WHAT THERE IS HIGHER CONFIDENCE IN WITH THIS FRONT ARE THE BREEZY
NORTHWEST WINDS AND STRONG CAA FOR FRIDAY AFTERNOON IN ITS WAKE.
HIGHS EVERYWHERE ON FRIDAY WILL LIKELY BE ACHIEVED EARLY ON...WITH
TEMPS SLOWLY FALLING THROUGH THE AFTERNOON. THE HIGH PRESSURE
RESPONSIBLE FOR THIS CAA WILL BE MOVING OVER MN BY SAT MORNING. THIS
COMBINED WITH MAINLY CLEAR SKIES WILL LEAD TO A CHILLY START TO THE
DAY ON SATURDAY...WITH BELOW ZERO LOWS LIKELY ONCE AGAIN FOR THE NW
CWA.

AFTER A COOL SATURDAY...CONFIDENCE STILL HIGH IN WAA KICKING IN IN A
BIG WAY SATURDAY NIGHT AS WE GET ON TO THE BACK SIDE OF THE
HIGH...WITH A VERY MILD PACIFIC AIRMASS ARRIVING FOR SUNDAY INTO
MONDAY. IN ADDITION...LOOKS LIKE WE COULD GET A FAIRLY CLEAN BURST
OF WARM AIR AS WELL...AS THIS WARMER AIR WILL BE ARRIVING ON CHINOOK
WINDS...WHICH SHOULD KEEP DEWPOINTS AND STRATUS/FOG IN CHECK.
CONTINUED TO NUDGE HIGHS UP ON BOTH DAYS...WITH JUST ABOUT EVERYONE
FORECAST TO GET INTO THE 40S BOTH DAYS. IN FACT...THE ECMWF
CONTINUES TO SHOW HIGHS AROUND 50 FOR MONDAY...SO AGAIN IF
ANYTHING...WE ARE PROBABLY NOT WARM ENOUGH. WE ALSO NOW HAVE IT DRY
FOR MONDAY...AS ALTHOUGH THE ECMWF IS STILL RUNNING ABOUT 12 HOURS
AHEAD OF THE GFS FOR A CLIPPER TYPE WAVE SUN NIGHT/MON...BOTH AGREE
ON KEEPING ANY OF ITS PRECIP WELL NORTH OF THE AREA.

TUESDAY...GFS/ECMWF AND ESPECIALLY THE GEM KICK OFF SOME PRECIP
ACROSS THE NRN PLAINS INTO MN OR IA AS THE REGION GETS INTO THE
RIGHT ENTRANCE REGION OF A JET THAT IS STRENGTHENING ACROSS THE
GREAT LAKES. HAVE CHANCE POPS IN FOR THIS FOR NOW...THOUGH NOT MUCH
CONFIDENCE IN IF WE WILL SEE ANYTHING AT THIS POINT. FOR
P-TYPE...KEPT THINGS SIMPLE FOR NOW WITH JUST A RAIN...SNOW...OR
RAIN/SNOW MIX MENTION BASED ON FORECAST SFC TEMPS.

&&

.AVIATION...(FOR THE 06Z TAFS THROUGH 06Z THURSDAY NIGHT)
ISSUED AT 1133 PM CST WED MAR 5 2014

DECK OF MVFR CIGS ARE SURGING NORTHWEST FROM IOWA INTO SOUTHWEST
MINNESOTA LATE THIS EVENING. MODELS INDICATE THIS DECK CONTINUING
LIFTING NORTH FOR THE NEXT FEW HOURS...AND THEN BEGIN LEANING TO
THE EAST LATE TONIGHT...DISSIPATING WHILE IT DOES SO. THUS...THINK
RWF...AXN...AND STC STAND THE BEST CHANCE AT EXPERIENCING THESE
CIGS...BUT CANNOT DISCOUNT MSP...RNH...AND EAU EITHER SINCE IT
SEEMS UNLIKELY THE FAIRLY CONTINUOUS STRATUS DECK WOULD DISSIPATE
ENOUGH TO PREVENT A CIG. BY THURSDAY AFTERNOON...STEEPENING LOW
LEVEL LAPSE RATES COULD CONTINUE THE MVFR CIG DEPENDING ON
TEMP/DEW POINT SPREADS AT THE SURFACE. FOR NOW...CONTINUED THE SCT
MENTION DUE TO UNCERTAINTY. SOUTH WINDS WILL INCREASE AND GUST
20-30 KT FROM LATE THURSDAY MORNING THROUGH AFTERNOON.

KMSP...WILL NEED TO WATCH SATELLITE AND OBSERVATION TRENDS TO GET
A BETTER FEEL FOR WHEN CIGS IF/WILL ARRIVE. AS OF THIS
WRITING...STARTING TO ALREADY SEE A FEW MORE CLOUDS DEVELOP TOWARD
MKT. THINK A 10Z START TIME FOR POTENTIAL OF THESE CLOUDS IS A
GOOD BET FOR NOW.

/OUTLOOK FOR KMSP/
FRI...MVFR/IFR WITH CHANCE OF FREEZING DRIZZLE IN THE MORNING.
WINDS NW 10-15 KT.
SAT...VFR. WINDS NW 5-10 KTS...BECOMING W 5 KT.
SUN...VFR. WINDS SW 5 KT.


&&

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

$$

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