Area Forecast Discussion
Issued by NWS Twin Cities, MN

Home | Current Version | Previous Version | Graphics & Text | Print | Product List | Glossary Off
Versions: 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50

000
FXUS63 KMPX 221156 AAA
AFDMPX

AREA FORECAST DISCUSSION...UPDATED
NATIONAL WEATHER SERVICE TWIN CITIES/CHANHASSEN MN
556 AM CST MON DEC 22 2014

.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 439 AM CST MON DEC 22 2014

CONFIDENCE IS FINALLY HIGH FOR TODAY AND TONIGHT. WHAT YOU SEE IS
PRETTY MUCH WHAT YOU GET TODAY. LOW CLOUDS AND OCCASIONAL LIGHT
RAIN OR DRIZZLE WILL PERSIST INTO THE LATE AFTERNOON AS LOW
PRESSURE SWINGS SOUTHEAST FROM EASTERN SOUTH DAKOTA INTO IOWA.
BACKING WINDS NORTH OF THE SYSTEM WILL INTRODUCE COLDER AIR INTO
THE SYSTEM LATE THIS AFTERNOON AND THIS EVENING...WITH THE LIGHT
RAIN OR DRIZZLE TURNING TO LIGHT SNOW FROM NORTHEAST TO SOUTHWEST.
LIFT IS NOT ALL THAT IMPRESSIVE...BUT THE MOISTURE DEPTH IS SO
THINK THERE WILL BE OCCASIONAL BOUTS OF LIGHT SNOW BUT NOTHING
THAT WILL ACCUMULATE ALL THAT AGGRESSIVELY...PARTICULARLY WITH
TEMPERATURES HOVERING NEAR FREEZING TONIGHT. QPF FOR THE NEXT 24
HOURS IS AT MOST FIFTEEN HUNDREDTHS OF AN INCH...AND TAKING INTO
ACCOUNT RAIN TODAY...WITH WET AND RELATIVELY MILD SURFACE
CONDITIONS TONIGHT...SNOW AMOUNTS WILL BE LESS THAN AN INCH
AREAWIDE.

IT SHOULD BE NOTED THE POP FORECAST WAS THE MOST DIFFICULT THING TO
HANDLE FOR THE SHORT TERM. THERE WILL BE MANY DRY HOURS OR
NON-MEASURABLE DRIZZLE...BUT COULD NOT PINPOINT THOSE HOURS EASILY.
THUS...VERY HIGH POPS PREVAIL THROUGH THE PERIOD WITH THE OCCASIONAL
QUALIFYING TERM ATTACHED TO THE WEATHER ELEMENTS.

.LONG TERM...(TUESDAY THROUGH SUNDAY)
ISSUED AT 439 AM CST MON DEC 22 2014

LONG TERM CONCERNS REMAIN THE TRANSITION OF MIXED RAIN/SNOW TO ALL
SNOW ON TUESDAY. THEN THE DEVELOPMENT OF TROUGH OVER THE OVER THE
WESTERN CONUS WITH POSSIBLE STORM DEVELOPMENT OVER NORTHERN
PLAINS/UPPER MISSISSIPPI VALLEY REGION THURSDAY AND FRIDAY.

MODELS CONTINUE TO INDICATE MAINLY SNOW ACROSS THE CWA FOR
TUESDAY MORNING AS THE UPPER LOW AND ASSOCIATED SURFACE LOW LIFTS
NORTHEAST OVER WISCONSIN. STRONGEST FORCING LIFTS OVER THE EASTERN
PORTION OF THE CWA DURING THE MORNING AS WELL. THIS SHOULD RESULT
IN THE BEST CHANCE FOR SNOW ACCUMULATION OVER THE AREA. CURRENTLY
HAVE 1 TO 3 INCHES OF ACCUMULATION FOR TUESDAY...WITH THE 2-3 INCH
AMOUNTS INTO A PORTION OF WEST CENTRAL WISCONSIN...MAINLY NORTH OF
I-94. COULD SEE A RAIN SNOW MIX DEVELOP AGAIN OVER THE EASTERN
AREAS INTO TUESDAY AFTERNOON AS THE STRONGER FORCING LIFTS
NORTHEAST. THIS ALONG WITH SURFACE TEMPERATURES STILL IN THE LOWER
AND MID 30S SHOULD KEEP SIGNIFICANT ACCUMULATIONS AT BAY. WILL
ISSUE AN ADVISORY FOR A COUPLE COUNTIES IN WEST CENTRAL WISCONSIN
WHERE CONFIDENCE IS HIGHER OF SEEING 3 INCHES OF SNOW ON TUESDAY.

SHOULD SEE NEAR SEASONAL TEMPERATURES IN THE WAKE OF THIS SYSTEM.
THE NEXT THREAT OF SNOW DEVELOPS LATER CHRISTMAS DAY INTO FRIDAY.
BOTH THE GFS AND THE ECMWF TREND ANOTHER TROUGH OVER THE WESTERN
CONUS WITH CYCLOGENESIS POSSIBLE. GFS ENSEMBLES SHOWING LARGE
SPREAD IN MOVEMENT OF ANY SURFACE LOW WITH POSSIBLE PHASING ISSUES
WITH THE TROUGH ENERGY AS WELL. THE TROUGH THAT IS RESPONSIBLE FOR
THIS THREAT IS CURRENTLY OVER THE THE EASTERN PACIFIC. WILL LIKELY
CONTINUE TO SEE VARIED SOLUTIONS FOR THIS SYSTEM UNTIL IT MOVES

&&

.AVIATION...(FOR THE 12Z TAFS THROUGH 12Z TUESDAY MORNING)
ISSUED AT 548 AM CST MON DEC 22 2014

LIFR OR IFR CONDITIONS TO PERSIST THROUGH THE PERIOD. NOT TOO MANY
CHANGES EXPECTED THROUGH MID AFTERNOON FROM WHAT IS ALREADY OUT
THERE. DRIZZLE AND RAIN WILL BECOME MORE WIDESPREAD THIS MORNING
WHICH COULD IMPACT VISIBILITIES ON A LOCAL BASIS AND SHORT TIME
SCALE. BIGGEST CONCERN IS THE TRANSITION FROM RAIN TO SNOW LATER THIS
AFTERNOON AS COLDER AIR ARRIVES. MODELS DIFFER A BIT ON THE TIMING
OF THIS DUE TO THE BOUNDARY LAYER HOVERING WITHIN A DEGREE OR TWO
OF FREEZING FOR SEVERAL HOURS. ACCUMULATIONS ARE ALSO SOMEWHAT
QUESTIONABLE DUE TO RELATIVELY MILD CONDITIONS. LESS THAN AN INCH
IS EXPECTED. SOUTHEAST WINDS WILL REMAIN IN THE 10-15KT RANGE FOR
MOST OF THE DAY...THEN SLOWLY BACK EAST THEN NORTHEAST
TONIGHT. ASIDE FROM TIMING OF SNOW...CONFIDENCE IS RATHER HIGH
OVERALL.

KMSP...HIGH CONFIDENCE THROUGH MID AFTERNOON...THEN UNCERTAINTY
ARISES WITH TIMING THE TRANSITION FROM RAIN TO SNOW. THERE MAY BE
SEVERAL HOURS OF A MIX BEFORE BECOMING ALL SNOW THIS EVENING.

/OUTLOOK FOR KMSP/
TUE...MVFR/IFR. -SN. WINDS NW 5-10 KTS.
WED...MVFR. WINDS NW 10-15 KTS.
THU...VFR. WINDS W 5-10 KTS.

&&

.MPX WATCHES/WARNINGS/ADVISORIES...
MN...NONE.
WI...WINTER WEATHER ADVISORY FROM MIDNIGHT TONIGHT TO 6 PM CST
     TUESDAY FOR WIZ016-027.

&&

$$

SHORT TERM...BORGHOFF
LONG TERM...DWE
AVIATION...BORGHOFF





USA.gov is the U.S. government's official web portal to all federal, state and local government web resources and services.