FXUS63 KMPX 142341
AFDMPX
AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE TWIN CITIES/CHANHASSEN MN
541 PM CST MON DEC 14 2009
.DISCUSSION...
FIRST ITEM OF THE FORECAST IS HEADLINE FOR WIND CHILL ADV OVER MN
PORTION OF THE CWA. COLD WIND CHILLS DEVELOPING AROUND MIDNIGHT
WEST...SPREADING TO THE ST CROIX RIVER VALLEY BY 12Z TUE. WILL
MENTION ADV FOR MN PORTION OF THE CWA LATE TONIGHT/TUE MORNING.
LEFTOVER FLURRIES OVER THE EASTERN CWA...WILL INCLUDE OVER THE FAR
EAST INTO THE EVENING. SOME INDICATION OF MID CLOUDS COMING BACK
OVER THE NORTHERN CWA OVERNIGHT AS UPPER TROUGH SWEEP OVER
NORTHERN MN. MAY DEVELOP A FLURRY AGAIN FAR NORTHERN CWA
OVERNIGHT...BUT THE MAIN MESSAGE IS THE ARCTIC CHILL MOVING IN.
TEENS BELOW LOOK LIKE A GOOD LIKELIHOOD OVER THE NORTHWEST CWA IF
CLOUDS CLEAR COMPLETELY...COMBINED WITH NEW SNOW COVER.
SFC RDG MOVING OVER THE CWA INTO TUE NIGHT. THIS SHOULD LEAVE
LITTLE IN THE WAY OF SIGNIFICANT RECOVERY TUESDAY. SHOULD SEE GOOD
DECLINE INTO TUE NIGHT BEFORE TEMPS SLOW THEIR DROP IN THE FAR
SOUTHWEST CWA. TRIED TO SHOW SOME TYPE OF NON-DIURNAL TREND THERE
LATE. SOME WARMING/MODERATION ANTICIPATED FOR WED INTO FRIDAY AS
SOME WEAK RIDGING ALOFT MOVES ACROSS THE REGION. THIS SHOULD
AFFECT MUCH OF THE CWA THURSDAY. SOME WEAK ISENTROPIC LIFT
ASSOCIATED WITH THE WARMER AIR...BUT MOISTURE LACKING AND MOVES
THROUGH RATHER QUICKLY. MENTION SLGT CHC POPS OVER THE FAR
NORTHEAST CWA THU WITH THIS.
LONGER TERM INDICATES HUDSON BAY VORTEX RETROGRADES INTO THE
WEEKEND. THIS WILL DRAG MORE CLOUDS AND THE THREAT OF SOME LIGHT
SNOW OR FLURRIES TO MUCH FOR THE REGION FRIDAY INTO
SUNDAY...MAINLY OVER THE EASTERN CWA. THIS WILL BRING A TREND BACK
TO COLDER TEMPERATURES AGAIN INTO THE WEEKEND.
&&
.AVIATION.../00Z TAF ISSUANCE/
EXPANSIVE ARCTIC HIGH PRESSURE CENTERED ACROSS THE DAKOTAS
GRADUALLY MOVING EAST TOWARDS THE TAF SITES TONIGHT. DEPARTING
STRATOCU OVER WRN WI CORRELATING WITH THE COLD AIR ADVECTION AREA
BEHIND THE ARCTIC FRONT. THIS WILL BE SLOWER TO PUSH EAST THAN IT
HAS ACROSS MN THIS AFTN...THUS LEAVING LINGERING 2 TO 4 KFT CIGS
OVER WI TAF SITES...PRIMARILY KEAU. SECONDARY UPPER DISTURBANCE
OVER SW ND EARLY THIS EVE WILL MOVE DUE EAST AND LIKELY LEAD TO
SOME OVERNIGHT CLOUDS AT TAF SITES. USING OBSERVATIONAL TRENDS IN
SW ND COMBINED WITH THE FORCING TRENDS OF THE UPPER DISTURBANCE IN
THE GUIDANCE FORECAST...DO EXPECT THERE TO BE SOME MVFR CIGS AROUND
NRN AND POSSIBLY ERN TAF SITES OVERNIGHT AND EARLY TOMORROW
MORNING. WINDS TO BE NW GRADUALLY TURNING WNW THROUGH THE FIRST 18
HOURS OF THE TAF AND THEN WSW AT THE END OF THE TAF PERIOD.
KAXN...CONSIDERING UPSTREAM CONDITIONS...HAVE ADDED SOME MVFR CIGS
TO RETURN EARLY OVERNIGHT WITH THE POSSIBILITY OF FLURRIES.
KSTC...CLOUDS SHOULD THIN SOON BUT THEN REAPPEAR LATE TONIGHT WITH
THE DISTURBANCE. SMALL CHANCE FOR MVFR CIGS RETURNING 07Z TO 11Z.
KRWF...MID CLOUDS OVERNIGHT WITH WINDS SLACKENING TUES. WINDS MAY
BACK AROUND TO THE SW QUICKER THAN FORECAST DEPENDING ON EXACT
TIME THE RIDGE AXIS MOVES OVER SW MN.
KMSP...LOWER CLOUDS TO THE EAST OF KMSP EARLY THIS EVE. SECONDARY
DISTURBANCE TO BRING THE INCREASING POSSIBILITY OF 3 TO 6 KFT
CIGS FROM 08Z TO 13Z.
KRNH...AIRPORT RIGHT AT THE EDGE OF THE BACKSIDE OF STRATOCU.
CONFIDENCE FOR MVFR CIGS IS GREATEST THROUGH 01Z THEN DROPS OFF.
SMALL CHANCE FOR RETURN FROM 09Z TO 14Z WITH SECONDARY DISTURBANCE.
KEAU...BANDS OF STRATOCU NEAR THE AIRPORT WILL KEEP MVFR
TEMPORARILY THROUGH MID EVE. MAY BE SOME LIGHT SNOW FOR A COUPLE
HOURS. EXPECT SOME GRADUAL LIFTING LATER TONIGHT BUT MAINLY A CIG
THROUGH EARLY TOMORROW MORNING.
&&
.MPX WATCHES/WARNINGS/ADVISORIES...
MN...WIND CHILL ADVISORY FROM MIDNIGHT TONIGHT TO 11 AM CST TUESDAY
FOR ANOKA-BENTON-BLUE EARTH-BROWN-CARVER-CHIPPEWA-CHISAGO-
DAKOTA-DOUGLAS-FARIBAULT-FREEBORN-GOODHUE-HENNEPIN-ISANTI-
KANABEC-KANDIYOHI-LAC QUI PARLE-LE SUEUR-MARTIN-MCLEOD-
MEEKER-MILLE LACS-MORRISON-NICOLLET-POPE-RAMSEY-REDWOOD-
RENVILLE-RICE-SCOTT-SHERBURNE-SIBLEY-STEARNS-STEELE-STEVENS-
SWIFT-TODD-WASECA-WASHINGTON-WATONWAN-WRIGHT-YELLOW
MEDICINE.
WI...NONE.
&&
$$
DWE/MTF
