572 
FXUS63 KMPX 011710
AFDMPX

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE TWIN CITIES/CHANHASSEN MN
1110 AM CST SAT JAN 1 2011

.UPDATE...
UPDATED TO INCLUDE 18Z AVIATION DISCUSSION BELOW.

&&

.DISCUSSION...
/ISSUED 411 AM CST SAT JAN 1 2011/
WITH BLIZZARD CONDITIONS IN THE DAKOTAS AND NEARING WESTERN
MN...TO TORNADO WARNINGS IN AL AND MS...AND A HARD FREEZE IN THE
SOUTHERN AZ DESERT...IT WOULD SEEM 2011 IS IN LIKE A LION. AND
2010 WAS CERTAINLY A LION IN WEATHER ACROSS THE UPPER
MIDWEST...BEING A STATISTICALLY IMPRESSIVE AND MAJOR IMPACTING
YEAR. ANY METEOROLOGIST OR WEATHER ENTHUSIAST SHOULD TAKE JUST A
MINUTE THIS NEW YEARS TO REFLECT ON THE NUMBERS AND MAGNITUDES OF
THE EVENTS...THE ANOMALOUS NATURE OF PARAMETERS...AND THE RECORDS
THAT WERE SHATTERED. FROM A SNOWLESS MARCH AND APRIL IN THE
WARMEST SPRING ON RECORD...TO A RECORD SEVERE WEATHER SEASON THAT
WAS DECEIVINGLY SLOW TO START BUT WOULD HOLD THE LARGEST TORNADO
OUTBREAK IN MN RECORDED HISTORY...TO A SUMMER THAT WAS WARMER AND
MOIST THAN MOST PROVIDING TWO INCH PWATS NINE TIMES AT MPX...TO A
SEPTEMBER DELUGE AND SUBSEQUENT RIVER FLOOD...FOLLOWED BY A LOW
PRESSURE BOMB BREAKING MN PRESSURE RECORDS...TO THE INCREDIBLE
START OF THIS WINTER SEASON WHERE WINTER STORMS HAVE BEEN ON A
CONVEYOR BELT INTO THE AREA...TO HALF TO THREE QUARTERS OF AN INCH
OF RAIN ON DEC 30TH AND SLEET/HAIL/GRAUPEL AND THUNDER ON NEW
YEARS EVE...2010 GAVE US EVENTS THAT WERE SOME OF THE MOST
INTRIGUING AND IMPACTING IN THE NATION. ON MULTIPLE OCCASIONS THIS
MADE MANY OF THE LONG TIME FORECASTING VETERANS HERE AT WFO MPX
COMMENT THEY HAD NEVER SEEN THAT BEFORE...AND WE MAY NOT AGAIN. SO
WHAT A WEATHER YEAR 2010 WAS.

SYNOPSIS...IMPRESSIVE UPPER LEVEL LOW ON WATER VAPOR SATELLITE IS
GRADUALLY MOVING NORTHEAST FROM WESTERN MN THIS MORNING. IN THE 
UPPER LEVELS...THE TROPOSPHERE FOLD IS ESTIMATED BY THE RUC TO BE
NEAR 600 MB...SHOWING THE AMOUNT OF DYNAMICS IN PLACE. DOUBLE-
BARRELED OCCLUDING LOW PRESSURE IS CENTERED FROM WESTERN LAKE
SUPERIOR TO CENTRAL MN THIS MORNING. THE TIGHT GRADIENT ON THE
WESTERN AND SOUTHERN FRINGES OF THIS HAS DRIVEN COLD AIR ADVECTION
WITH TEMPERATURES NEAR ZERO ACROSS MUCH OF THE MN FORECAST AREA.
EVEN A TIGHTER GRADIENT EXISTS IN THE EASTERN DAKOTAS AND
NORTHWEST IA AND WILL PASS OVER THE AREA THIS MORNING AS THE LOW
PRESSURE PULLS NORTHEAST AND GRADUALLY FILLS. WINDS ARE GUSTING TO
30 TO 40 KTS IN THE EASTERN AND CENTRAL DAKOTAS. WESTERN MN
SNOWFALL AMOUNTS SINCE FRIDAY AFTERNOON ARE ESTIMATED TO BE
BETWEEN TWO AND FIVE INCHES...AND FOUR TO TEN INCHES SINCE
THURSDAY AFTERNOON. THIS FRESH POWDER WILL CONTINUE TO TAKE TO THE
AIR IN THE WINDS TODAY.

TODAY AND TONIGHT...UPSTREAM PROFILERS IN THE DAKOTAS ARE
INDICATING 35 KTS AT 925 MB AND THIS WILL BE MOVING INTO WESTERN
MN SOON AFTER DAYBREAK. AS LOW-LEVEL LAPSE RATES CONTINUE TO
STEEPEN TO DRY ADIABATIC...MIXING WILL BE EVERY BIT THIS DEEP AND
LIKELY DEEPER. MODEL SOUNDINGS FROM WESTERN MN SHOW MIX DOWN
POTENTIAL OF 40 TO 45 KNOTS POSSIBLE IN FAR WESTERN MN AND THE MN
RIVER VALLEY CORRIDOR OF SOUTHWEST MN. THE 31.21 SREF HAD 25
PERCENT OF ITS MEMBERS INDICATING GUSTS TO 40 MPH...AND THINK THAT
SOME SITES SHOULD SEE THAT WITH THE AFOREMENTIONED ISALLOBARICS
ALSO IN PLACE. SO WINDS WILL BE RIGHT THERE FOR BLIZZARD CRITERIA.
WRAPAROUND WARM AIR ADVECTION AND ISENTROPIC ASCENT FROM THE
NORTHWEST ON A FORM OF SYSTEM TROWAL WILL CONTINUE TO SUPPORT
FALLING SNOW ACROSS A LARGE PORTION OF THE MN FORECAST AREA
TODAY...PARTICULARLY THE NORTHWEST FORECAST AREA. HAVE BUMPED UP
POPS CONSIDERABLY...BUT THINKING MAINLY A HIGH POP/LOW QPF DAY.
WHAT THE FALLING SNOW WILL DO IS ADD TO LOW VISIBILITY DUE TO
BLOWING SNOW TO MAKE FOR THE BLIZZARD CONDITIONS IN WESTERN MN.
THE SLOWER MODEL SOLUTION TIMING OF THE FORCING OF SNOWFALL AND
THE DEPARTURE OF WIND MECHANISMS POINTS TOWARDS POOR CONDITIONS
LASTING INTO THIS AFTERNOON. KNOWING WESTERN MN USUALLY HAS ISSUES
WITH BLOWING SNOW...ESPECIALLY WITH THE AMOUNT OF FRESH POWDERY
SNOW /AND THEY DID NOT RECEIVE ICE OR RAIN ON TOP OF IT/...HAVE
GONE AHEAD AND EXTENDED THE BLIZZARD WARNING AND WINTER WEATHER
ADVISORY. WIND CHILLS LOOK TO MODERATE SLIGHTLY THIS
AFTERNOON...SO THE WIND CHILL ADVISORY WILL STILL END AT NOON.
ADDITIONAL SNOWFALL AMOUNTS OF ONE HALF TO ONE AND A HALF INCHES
SEEM MOST PLAUSIBLE ACROSS THE HEADLINED AREAS...WITH POSSIBLY UP
TO A HALF INCH IN THE TWIN CITIES. CONDITIONS SHOULD IMPROVE
QUICKLY LATE THIS AFTERNOON AND TONIGHT AS FORCING DISSOLVES.
CLOUD COVER SHOULD EVEN PULL OUT WITH DRY AIR WRAPPING AROUND THE
SYSTEM INTO THE AREA BY DAYBREAK SUNDAY.

SUNDAY NIGHT THROUGH MONDAY NIGHT...THE NEXT WEATHER SYSTEM /SEE
CONVEYOR BELT MENTION ABOVE/ WILL RESEMBLE MORE OF A CLIPPER TYPE
SYSTEM. WARM AIR ADVECTION FROM THIS WILL ENSUE SUNDAY NIGHT ALONG
A TIGHTENING ELEVATED BAROCLINIC ZONE. MOISTURE THROUGH THE ENTIRE
PROFILE IS SLOW TO BE REALIZED WITHIN FAIRLY WEAK ASCENT...BUT AS
THE 700MB WAVE NEARS AND PASSES MONDAY AFTERNOON/EVENING...SNOW IS
BECOMING MORE PROBABLE OVER CENTRAL MN INTO WESTERN WI. IF THE
WARM AIR ADVECTION SIDE OF THIS CLIPPER CAN SATURATE...STARTING
ACCUMULATING SNOW EARLIER...IT IS POSSIBLE THIS COULD BE AN
ADVISORY TYPE EVENT. THERE WILL BE ANOTHER SHOT OF COLD AIR
ADVECTION WITH THIS SYSTEM ON MONDAY NIGHT INTO EARLY TUESDAY.

BEYOND...THE NEXT CLIPPER TYPE SYSTEM APPEARS TO ARRIVE SOMETIME
IN THE MIDDLE OF THE WEEK...WITH A MODEL CONSENSUS ON WEDNESDAY
AFTERNOON/EVENING. THIS TOO HAS AN ELEVATED BAROCLINIC ZONE AND
SURFACE REFLECTION SO WILL NEED TO BE MONITORED. HAVE MADE NO
CHANGES TO THE GOING POPS FOR THIS. UNSETTLED WEATHER...2010
STYLE...IS GENERALLY FORECAST BY THE DETERMINISTIC AND LONG RANGE
ENSEMBLES INTO NEXT WEEKEND.

&&

.AVIATION.../18Z TAF ISSUANCE/ 
WINDS AND THE ASSOCIATED BLOWING SNOW AND REDUCED VISIBILITIES ARE
THE MAIN AVIATION ISSUE FOR AT LEAST THE NEXT 6-8 HOURS BEFORE
WINDS QUIET DOWN. SOME MVFR CEILINGS ARE ALSO PRESENT... ALTHOUGH
THEY ARE TENDING TO DIMINISH SOME WITH TIME AS THE 925-850MB
THERMAL TROUGH IS STARTING TO PUSH OFF TO THE EAST AND NORTHEAST A
BIT AND WE/RE SEEING SOME BOUNDARY LAYER WARM ADVECTION AND
ASSOCIATED LOWERING OF RH VALUES. HOWEVER... STILL EXPECT SOME
MVFR CEILINGS THROUGH THE DAY UNTIL WE/RE ABLE TO GET SOME
ANTICYCLONIC FLOW INTO THE AREA TONIGHT. WINDS WILL CONTINUE TO
GUST ABV 25KT THROUGH THE DAY... BUT SHOULD QUIET DOWN FAIRLY
QUICKLY THIS EVENING.

KMSP... TAF REFLECTS OVERALL THOUGHTS WELL... ALTHOUGH THERE IS
SOME UNCERTAINTY AS TO HOW MUCH VISIBILITIES WILL CONTINUE TO BE
IMPACTED THIS AFTERNOON SINCE MOST OF THE REDUCTION WILL NEED TO
BE DUE TO BLOWING SNOW SINCE FALLING SNOW IS DIMINISHING... AND
THE DEGREE OF BLOWING SHOULD BE LIMITED GIVEN THE MINIMAL FRESH
SNOW ON THE GROUND. SO... MAY NEED TO ADJUST VISIBILITIES UPWARD
IN THE FIRST 6 HOURS OF THE TAF DEPENDING UPON HOW THINGS
EVOLVE... BUT KEPT THINGS RESTRICTED FOR NOW GIVEN CURRENT
CONDITIONS AND UPSTREAM/SURROUNDING OBS. CEILINGS SHOULD NOT BE A
SIGNIFICANT ISSUE... WITH ANY SUB-2K FT VALUES BEING TEMPORARY AND
ISOLATED.

&&

.MPX WATCHES/WARNINGS/ADVISORIES...
MN...BLIZZARD WARNING UNTIL 4 PM CST THIS AFTERNOON FOR CHIPPEWA-
     DOUGLAS-LAC QUI PARLE-POPE-STEVENS-SWIFT-YELLOW MEDICINE.

     WINTER WEATHER ADVISORY UNTIL 4 PM CST THIS AFTERNOON FOR BENTON-
     KANABEC-KANDIYOHI-MEEKER-MILLE LACS-MORRISON-REDWOOD-
     RENVILLE-STEARNS-TODD.

     WIND CHILL ADVISORY UNTIL NOON CST TODAY FOR BLUE EARTH-BROWN-
     FARIBAULT-FREEBORN-MARTIN-STEELE-WASECA-WATONWAN.

WI...NONE.
&&

$$

TRH/MTF/TRH