000
FXUS63 KMPX 090607 AAB
AFDMPX

AREA FORECAST DISCUSSION...UPDATED
NATIONAL WEATHER SERVICE TWIN CITIES/CHANHASSEN MN
1207 AM CST MON DEC 9 2013

.SHORT TERM...(THIS EVENING THROUGH MONDAY)
ISSUED AT 342 PM CST SUN DEC 8 2013

THE SNOW NEVER REALLY MATERIALIZED LIKE HOW WE ORIGINALLY THOUGHT
IT WOULD YESTERDAY WHEN WE ISSUED THE WINTER WEATHER ADVISORY.
IT HAS BEEN SNOWING STEADILY MOST OF THE DAY ACROSS MUCH OF THE
FORECAST AREA...HOWEVER THE CRYSTALS ARE VERY FINE AND SNOW
ACCUMULATION HAS BEEN DIFFICULT. THE LIGHT SNOW WILL CONTINUE
THROUGH THE EVENING AND DIMINISH FROM WEST TO EAST BETWEEN 00-06Z.
MOST LOCATIONS WILL ONLY SEE AN ADDITIONAL QUARTER INCH OF SNOW OR
LESS FOR THE REMAINDER OF THIS EVENT. THE ADVISORY WILL NEED TO BE
CANCELLED EARLY...BUT BECAUSE IT IS STILL SNOWING AND THE
CHARACTER OF THE SNOW COMBINED WITH CURRENT COLD TEMPS IS LEADING
TO ACCIDENTS...WE DECIDED NOT TO CANCEL WITH THE AFTERNOON
FORECAST PACKAGE.

THE SURFACE LOW SOUTH OF THE FORECAST AREA TODAY WILL DEEPEN OVER
THE WARMER GREAT LAKES AND THIS WILL INCREASE THE PRESSURE GRADIENT
ACROSS MN TOMORROW MORNING WITH THE BUILDING SURFACE HIGH OVER THE
HIGH PLAINS. THIS WILL SERVE TO INCREASE WINDS FROM 09-21Z
TOMORROW. THEREFORE...A PATCHY BLOWING SNOW IS POSSIBLE ACROSS
PORTIONS OF MN. WE WILL SEE GOOD COLD AIR ADVECTION IN THE SFC-
850MB LAYER OVER THE NEXT 24 HOURS...SO TEMPERATURES WILL DROP FROM
WHERE WE ARE NOW THIS AFTERNOON EVEN WITH CLOUD COVER HANGING TOUGH
TONIGHT. THE TEMP MAY GO SIDEWAYS TOMORROW WITH LITTLE WARMING
ANTICIPATED.

.LONG TERM...(MONDAY NIGHT THROUGH SUNDAY)
ISSUED AT 342 PM CST SUN DEC 8 2013

MODELS REMAIN IN GOOD AGREEMENT ON THE WEATHER PATTERN THROUGH
WEDNESDAY...BUT BEGIN TO DIVERGE QUITE A BIT...ESPECIALLY WITH SFC
FEATURES DURING THE SECOND HALF OF NEXT WEEK. THE REASON FOR THE
DIVERGENCE? DISAGREEMENT IN A PATTERN SHIFT AT THE END OF NEXT
WEEK AS OUR CURRENT HIGHLY AMPLIFIED PATTERN WITH A RIDGE UP INTO
ALASKA AND A DEEP POLAR VORTEX DOWN ACROSS CANADA TRANSITIONS TO
TROUGHING OUT OVER THE GULF OF ALASKA...WITH A MORE ZONAL FLOW
DEVELOPING ACROSS THE CONUS.

THROUGH WEDNESDAY WE WILL CONTINUE OUR RESIDENCE WITHIN A COLD AND
DRY ARCTIC AIRMASS. THIS PATTERN WILL FEATURE A COUPLE OF QUICK
MOVING SHORT WAVES THAT MAY BE ABLE TO SHAKE OUT SOME LIGHT SNOW
SHOWERS...BUT IT DOES NOT LOOK LIKE ANYTHING SIGNIFICANT AT THIS
POINT. THE FIRST WAVE IS PROGGED BY GUIDANCE TRACK SE ACROSS NODAK
AND NRN MN AND WI MONDAY NIGHT. 275K ISENTROPIC SFCS FROM THE
GFS/NAM SNOW A QUICK BURST OF LIFT WORKING ACROSS CENTRAL MN/WRN WI
AHEAD OF THE WAVE MONDAY NIGHT. AT THE MOMENT...EVERYTHING POINTS TO
A QUICK HALF INCH OF SNOW FALLING ACROSS AREAS NORTH OF I-94. THE
SECOND WAVE SWINGS THROUGH TUESDAY EVENING INTO TUESDAY NIGHT. THIS
TIME AROUND THE SNOW WILL BE THE RESULT OF STRONG FGEN ON THE SRN
EDGE OF THE ARCTIC AIR. AS EXPECTED...THERE IS DISAGREEMENT WHERE
THIS BAND OF SNOW WILL TRACK...BUT THERE IS GOOD ENOUGH AGREEMENT ON
SOMETHING MOVING ACROSS SW AND SC MN TO INCLUDE SOME CHANCE POPS
DOWN THERE. AGAIN...THIS LOOKS LIKE NOTHING MEANINGFUL WITH MAYBE A
HALF INCH OF SNOW POSSIBLE.

BESIDE THESE COUPLE OF SNOW CHANCES...WE WILL MAINTAIN TEMPERATURES
THAT ARE A GOOD 20 TO 25 DEGREES BELOW NORMAL. THE COLDEST DAY IN
THE LONG TERM LOOKS TO BE WEDNESDAY AS ANOTHER 1040 MB HIGH HEADS
FOR SRN MN AND IOWA. AIRMASS WITH THIS HIGH LOOKS VERY SIMILAR TO
WHAT WE SAW SUNDAY...SO WEDNESDAY IS LOOKING TO BLW 5 ABOVE DOWN
ALONG I-90. WE WILL CONTINUE TO SEE LOWS WELL BELOW ZERO TONIGHT
THROUGH WEDNESDAY NIGHT AS WELL...WITH AT LEAST WIND CHILL
ADVISORIES NEEDED FOR PARTS OF THE AREA EACH NIGHT. OF THESE
NIGHTS...TUESDAY NIGHT LOOKS THE COLDEST...WHEN CURRENT APPARENT
TEMP FORECAST INDICATES THE POTENTIAL FOR ANOTHER WIND CHILL WARNING
ACROSS WRN AND CENTRAL MN...WITH EVERYONE ELSE NEEDING A WIND CHILL
ADVISORY.

FOR THE END OF THE PERIOD...GIVEN THE MODEL DISAGREEMENT...STUCK
WITH THE CONSERVATIVE BLEND AT THIS POINT. THAT BLEND IS FAVORED
MORE TOWARD THE MILDER GFS....WHICH KEEPS AN ARCTIC HIGH
FRIDAY/SATURDAY UP IN CANADA. THE ECMWF BRINGS A 1040 MB HIGH DOWN
ALONG THE INTERNATIONAL BORDER...WITH ARCTIC AIR RETURNING TO THE
AREA THURSDAY NIGHT AFTER A BRIEF RESPITE ON THURSDAY. AS WE TURN TO
THE NEXT WEEK...THE GFS/ECMWF CONTINUE TO SHOW MUCH MILDER AIR
COMING BACK TO THE UPPER MS VALLEY /H85 TEMPS ON THE PLUS SIDE OF
0C/...BUT THIS IS A STOUT ARCTIC AIRMASS IN PLACE AND IT WILL LIKELY
BE TOUGH TO NUDGE IT OUT OF HERE IN THE MIDDLE OF DECEMBER...BUT IT
DOES LOOK LIKE WE WILL AT LEAST SEE TEMPERATURES RETURN BACK TO
THEIR PROPER LEVELS FOR MID DECEMBER.

&&

.AVIATION...(FOR THE 06Z TAFS THROUGH 06Z MONDAY NIGHT)
ISSUED AT 1131 PM CST SUN DEC 8 2013

SNOW IS TAPERING OFF FROM SOUTHWEST TO NORTHEAST AND SOUTHWEST MN
HAS CLEARED OUT. A RAPID CLEARING OF CLOUDS WILL FOLLOW THE
DISSIPATION OF SNOW WITH SKC EXPECTED MOST EVERYWHERE BY SUNRISE.
WINDS WILL BECOME GUSTY MONDAY AND COULD LEAD TO SOME BLOWING SNOW
TOWARD AXN...RWF...AND STC. WINDS WILL SHIFT SOUTHERLY MONDAY
EVENING WITH INCREASING MID LEVEL CLOUDS LATE.

KMSP...SNOW IS TAPERING OFF AND WILL END SHORTLY. CIGS CONTINUE TO
BOUNCE AROUND...BUT AFTER THE SNOW ENDS CIGS WILL BE VFR. WEST
WINDS WILL INCREASE LATE TONIGHT AND COULD GUST TO 20 KTS LATE
MONDAY MORNING AND AFTERNOON.

/OUTLOOK FOR KMSP/
TUE...VFR. WINDS W 15G25KTS.
WED...VFR. WINDS W 5-10KTS.
THU...VFR. WINDS SW 5 KTS.

&&

.MPX WATCHES/WARNINGS/ADVISORIES...
MN...WIND CHILL ADVISORY FROM 3 AM TO NOON CST MONDAY FOR MNZ043>045-
     049>053-057>063-065>070-073>077-082>085-091>093.

     WIND CHILL ADVISORY UNTIL NOON CST MONDAY FOR MNZ041-042-047-048-
     054>056-064.

WI...NONE.
&&

$$

SHORT TERM...CLF
LONG TERM...MPG
AVIATION...BORGHOFF