830 
FXUS63 KMPX 310000
AFDMPX

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE TWIN CITIES/CHANHASSEN MN
600 PM CST MON DEC 30 2013

.SHORT TERM...(THIS EVENING THROUGH TUESDAY)
ISSUED AT 340 PM CST MON DEC 30 2013

TONIGHT THROUGH TUESDAY...SWATH OF LIGHT SNOW CONTINUES LATE THIS 
AFTN...ASSOCIATED WITH A MODEST UPR LEVEL SHORTWAVE TROF AXIS AND A 
COMPACT SFC LOW PRES CENTER DRIVING EWD FROM WRN IA INTO NRN IL. 
HAVE SEEN REPORTS OF MAINLY ONE HALF TO ONE AND HALF INCHES OF NEW 
SNOW...WITH SNOWFALL BEING LIMITED BY SUCH A DRY ATMOS. THIS WEAK 
SYSTEM WILL EXIT TO THE SE THIS EVENING BEING IMMEDIATELY FOLLOWED 
BY HIGH PRES WHICH WILL CLEAR SKIES OUT AND DIMINISH WINDS. ANOTHER 
CHUNK OF ARCTIC AIR WILL BE BROUGHT DOWN WITHIN THE PRONOUNCED NW 
FLOW ALOFT. SO...EVEN WITH NE WINDS IN THE 5-10 MPH RANGE...WIND 
CHILLS WILL COMMONLY DROP TO AS LOW AS -40 DEG F. THEREFORE...HAVE 
OPTED TO ISSUE ANOTHER WIND CHILL ADVY BUT ALSO INCLUDED A FEW 
COUNTIES IN A WIND CHILL WRNG...PARTICULARLY IN CENTRAL MN. WIND 
CHILLS WILL STILL REMAIN DANGEROUSLY LOW THRU LATE TUE MRNG THEN 
IMPROVEMENT ABOVE WIND CHILL THRESHOLDS IS EXPECTED TMRW AFTN. HIGH 
PRES WILL THEN RETREAT TO THE NE AS ANOTHER AREA OF LOW PRES 
DEVELOPS OVER THE CENTRAL PLAINS STATES AND DRIFTS SE. WEAK 
ISENTROPIC LIFT IN ADVANCE OF THE WMFNT OF THIS SYSTEM COMBINED WITH 
INCREASED MOISTURE IN THE 1000-5000MB MOISTURE COLUMN WILL ALLOW FOR 
ADDITIONAL LIGHT SNOW ACCUMULATIONS OVER SWRN AND FAR SRN MN 
STARTING TMRW AFTN. STILL SOME ISSUES WITH WHERE THE HIGHLIGHT OF 
THE ACCUMULATIONS WILL BE...AS IN OVER SRN MN OR NRN IA...BUT MOST 
GUIDANCE /INCLUDING MODEL AND WPC/ INDICATES THAT THE HIGHEST 
ACCUMULATIONS WILL BE INTO NRN IA THEN DROPS OFF WITHIN A ROW OF 
COUNTIES IN FAR SRN MN. ATTM...AM THINKING ACCUMULATIONS WILL BE 
LIMITED TO AN INCH OR TWO BUT THIS COULD EASILY GO HIGHER IF THE 
TRACK OF THIS SYSTEM IS NUDGED N BECAUSE SUFFICIENT MOISTURE... AND 
ESPECIALLY MOISTURE WITHIN THE DENDRITIC GROWTH ZONE...WILL 
ACCOMPANY THIS SYSTEM. AS FOR TEMPS...LOWS TONIGHT WILL RANGE FROM 
AROUND -10 DEG F NEAR THE IA BORDER TO AS LOW AS -25 DEG F IN 
CENTRAL MN. HIGHS ON TUE WILL BE COLDER THAN TDA...RANGING FROM 4 
ABOVE ZERO TO 10 BELOW ZERO.

.LONG TERM...(TUESDAY NIGHT THROUGH MONDAY)
ISSUED AT 340 PM CST MON DEC 30 2013

SURFACE HIGH PRESSURE DRIFTS INTO THE AREA ON TUESDAY NIGHT INTO
WEDNESDAY MORNING...WHICH WILL LIKELY SUPPRESS MEASURABLE SNOW TO
THE SOUTH. HAVE TAPERED SNOW CHANCES TO BELOW 30 PERCENT FOR
WEDNESDAY. TUESDAY NIGHT LOWS WILL DIP TO BETWEEN ZERO AND 15
BELOW...WITH WEDNESDAY HIGHS MOSTLY IN THE SINGLE DIGITS ABOVE
ZERO. AS SURFACE HIGH PRESSURE PREVAILS AGAIN ON
THURSDAY...TEMPERATURES WILL REMAIN COMPARABLE TO WEDNESDAY. WEAK
RIDGING BUILDS IN ON FRIDAY AS A SURFACE TROUGH ENTERS THE
NORTHERN PLAINS. FRIDAY AND SATURDAY HIGHS WILL MODERATE TO
BETWEEN 15 AND 25 DEGREES...AND BE ACCOMPANIED BY SNOW CHANCES ON
FRIDAY NIGHT-SATURDAY AS THE FRONT AND ASSOCIATE TROUGH SWING
ACROSS THE AREA. THERE IS STILL RELATIVELY LOW CONFIDENCE ON
SNOWFALL AMOUNTS FOR THE WEEKEND...WITH THE GEM THE MOST
AGGRESSIVE /3-4 INCHES BY SATURDAY MORNING/...THE GFS IN THE
MIDDLE /0.5-2 INCHES/...AND THE ECMWF THE LOWEST /TRACE-1 INCH/.
FOR NOW...HAVE JUST INCLUDED LOW POPS UNTIL THE AMPLITUDE/TEMPORAL
DETAILS BECOME MORE CERTAIN. WHAT IS MORE CERTAIN HOWEVER...IS
THAT YET ANOTHER BLAST OF EXTREMELY COLD AIR WILL ARRIVE BEHIND
THE SYSTEM FOR MONDAY. MODELS FEATURE -27C /GFS/ TO -37C /ECMWF/
850 TEMPS ACROSS THE AREA FOR 12Z MONDAY. HAVE INCLUDED A FALLING
TEMP TREND DURING THE DAY ON MONDAY...WITH READINGS DROPPING TO BETWEEN
10 AND 15 BELOW BY LATE AFTERNOON ACROSS MUCH OF THE AREA. MONDAY
NIGHT COULD BE IN COMPETITION FOR THE COLDEST NIGHT OF THE SEASON
THUS FAR...WITH THE ECMWF INDICATING THE POTENTIAL FOR WIDESPREAD
20 BELOW TO 30 BELOW READINGS...WITH THE GFS NOT MUCH WARMER.

&&

.AVIATION...(FOR THE 00Z TAFS THROUGH 00Z TUESDAY EVENING)
ISSUED AT 600 PM CST MON DEC 30 2013

LIGHT SNOW ACROSS THE TWIN CITIES...WEST CENTRAL WI AND SOUTH
CENTRAL MN WILL END THIS EVENING AS A WAVE OF LOW PRESSURE OVER
WESTERN IA MOVES SE. VFR CONDITIONS ARE TRYING TO PUSH ACROSS
CENTRAL MN AND THE MN RIVER VALLEY...BUT POCKETS OF MVFR CEILINGS
ARE STILL OUT THERE PER THE LATEST OB FROM KAXN. EVENTUALLY THINGS
WILL IMPROVE THIS EVENING FROM NW TO SE. THE NEXT LOW IN THE
ARCTIC WAVE TRAIN WILL BRING MVFR/IFR CIGS/VSBYS TO KRWF TUESDAY
AFTERNOON AND NIGHT. IT APPEARS THE OTHER TAF SITES WILL BE
DRY/VFR THROUGH THE DAY. WINDS BECOMING NW LESS THAN 10 KNOTS EARLY
TONIGHT AND CONTINUING ON TUESDAY.

KMSP...CONDITIONS ARE IMPROVING TO VFR AROUND THE TWIN CITIES AT
TAF ISSUANCE BUT THERE REMAINS POCKETS OF MVFR CIGS/VSBYS THAT MAY
AFFECT THE AIRFIELD THROUGH 02Z. THEREAFTER...VFR WITH LIGHT NW
WINDS THROUGH TUESDAY.

/OUTLOOK FOR KMSP/
TUE NGT/WED...VFR. CHC MVFR/-SN. WINDS NE 5 TO 10 KTS.
THU...VFR. WINDS NW 5 KTS.
FRI...VFR. WINDS SSE 10-20 KTS.

&&

.MPX WATCHES/WARNINGS/ADVISORIES...
MN...WIND CHILL ADVISORY FROM 9 PM THIS EVENING TO NOON CST TUESDAY 
     FOR MNZ047>053-055>063-065>070-075>078-083>085.

     WIND CHILL WARNING FROM 9 PM THIS EVENING TO NOON CST TUESDAY 
     FOR MNZ041>045.

WI...WIND CHILL ADVISORY FROM 9 PM THIS EVENING TO NOON CST TUESDAY 
     FOR WIZ014>016-023>028.

&&

$$

SHORT TERM...JPC
LONG TERM...LS
AVIATION...RAH