000 FXUS63 KMPX 190946 AFDMPX AREA FORECAST DISCUSSION NATIONAL WEATHER SERVICE TWIN CITIES/CHANHASSEN MN 346 AM CST TUE FEB 19 2008 .DISCUSSION... CLOSED LOW ALOFT OVER WESTERN ONTARIO EARLY THIS MORNING. FEATURE IS DROPPING ALMOST DUE SOUTH AND WILL PASS ACROSS THE REGION DURING THE AFTERNOON AND EVENING HOURS. A SURGE OF LOW LEVEL WAA AHEAD OF THE NEXT ARCTIC FRONT COUPLED WITH DECENT UPGLIDE AND Q-VECTOR CONVERGENCE SHOULD PRODUCE SOME LIGHT SNOW ACROSS SW AND SOUTHERN MN BY LATE THIS MORNING WITH AN INCREASE OVER FAR EASTERN MN AND WEST CENTRAL WI DURING THE AFTERNOON HOURS. LAPSE RATES ARE STEEP ONCE AGAIN TODAY FROM 950 TO 850 MB WITH 8.6 DEG C/KM PROGGED DURING THE AFTERNOON OVER THE EASTERN CWA. EVEN SOME LOW LEVEL CAPE SEEN. THEREFORE WENT QUITE A BIT ABOVE THE VARIOUS MOS GUIDANCE PRODUCTS. USED CHANCE POPS OVER EASTERN AND SOUTHERN MN INCREASING TO LIKELY POPS FOR A TIME NEAR EAU CLAIRE DURING THE LATE AFTERNOON. STRONG HIGH PRESSURE WILL BUILD OVER THE EASTERN DAKOTAS AND WESTERN MN BY DAYBREAK WEDNESDAY. VERY DRY AIR ASSOCIATED WITH THE HIGH WITH DEW POINTS WELL INTO THE MINUS 20S NORTH OF US THIS MORNING. CUT MOS LOWS FOR WEDNESDAY AND THURSDAY MORNING AND TRIMMED BACK ON THE HIGHS FOR WEDNESDAY AS WELL. BRISK NW WINDS IN THE WAKE OF THE ARCTIC FRONT TONIGHT. APPARENT TEMPERATURE GRID INDICATED MINUS 25 BY 00Z IN THE WESTERN CWA AND AROUND 06Z IN THE EAST. WILL BE ISSUING A WIND CHILL ADVISORY FOR THE CWA STARTING WITH THE TIMES ABOVE AND CONTINUING IT THROUGH NOON WEDNESDAY. ECMWF AND GFS PRETTY CONSISTENT ON BRINGING ANOTHER NORTHERN STREAM SHORT WAVE ACROSS THE UPPER MISSISSIPPI VALLEY ON THURSDAY. AS A RESULT...INCREASED CLOUDS AND ADDED SOME SMALL POPS FOR NOW. MORE HIGH PRESSURE IN THE WAKE OF THIS FEATURE. COLLABORATION YIELDED DROPPING LOWS AND HIGHS HEADING INTO THE WEEKEND. 00Z MEX GUIDANCE LOOKED GOOD AND WAS USED. && .AVIATION.../06Z TAF ISSUANCE/ VFR CONDITIONS DOMINATE ACROSS THE AREA LATE THIS EVENING WITH ONLY ISOLATED MVFR CIGS WITH A FEW FLURRIES OR LIGHT SNOW SHOWERS LINGERING ACROSS WEST CENTRAL WISCONSIN. WINDS HAVE ALSO SUBSIDED AND WILL BECOME MORE WESTERLY OVERNIGHT. MAIN CONCERN SHIFTS TO APPROACHING UPPER LOW MOVING SOUTHWARD OUT OF MANITOBA AND WESTERN ONTARIO. TWO AREAS OF UPPER ENERGY LOOK TO CROSS THE AREA TUESDAY AND TUESDAY EVENING WITH THE FIRST WAVE MOST LIKELY TO BRING SOME LIGHT SNOW SHOWERS. A SFC TROUGH WILL ALSO CROSS THE AREA DURING THE AFTERNOON. GENERALLY CLEAR SKIES TONIGHT WILL GIVE WAY TO SOME MID LEVEL CLOUDINESS TOWARDS MORNING WITH LOWER END VFR DECK AROUND 5 TO 7 KFT BUILDING AFTER DAYBREAK FROM NORTHWEST TO SOUTHEAST. TRACK OF UPPER ENERGY SUGGESTS BEST CHANCE FOR SNOWFALL POTENTIAL ACROSS EAST CENT MN AND WEST CENT WI STARTING DURING THE MID TO LATE MORNING HOURS AND ENDING EARLY AFTERNOON. WINDOW OF SNOWFALL SHOULD ONLY BE A FEW HOURS DUE TO LIMITED MOISTURE AVAILABLE IN THE ALREADY COLD AND DRY AIRMASS. HAVE CONTINUED WITH PROB 30 MENTION FOR SNOW. EXPECT 2 TO 5 SM VIS IN SNOW SHOWERS THAT CAN DEVELOP...WITH ISOLATED BRIEF VIS TO AROUND A MILE POSSIBLE. WINDS WILL SHIFT BACK TO THE NORTHWEST DURING THE AFTERNOON BEHIND THE TROUGH PASSAGE AND INCREASE IN SPEED WITH SUSTAINED SPEEDS OF 15 TO 20 KTS ACROSS THE MN SITES WITH SOME GUSTS TO 25 TO 30 KTS...WITH THE UPPER END OF THOSE RANGES EXPECTED ACROSS WEST CENTRAL MN AND LOWER END TO THE EAST DURING THE LATE AFTERNOON. WILL NEED TO MONITOR CLOUD TRENDS BEHIND THIS SYSTEM BUT SCATTERING OF LOWER CLOUDS LOOKS REASONABLE DURING TUESDAY EVENING. && .MPX WATCHES/WARNINGS/ADVISORIES... MN...WIND CHILL ADVISORY FROM MIDNIGHT TONIGHT TO 12 PM CST WEDNESDAY FOR ANOKA-BLUE EARTH-CARVER-CHISAGO-DAKOTA-FARIBAULT- FREEBORN-GOODHUE-HENNEPIN-ISANTI-LE SUEUR-RAMSEY-RICE-SCOTT- STEELE-WASECA-WASHINGTON. WIND CHILL ADVISORY FROM 6 PM THIS EVENING TO 12 PM CST WEDNESDAY FOR BENTON-BROWN-CHIPPEWA-DOUGLAS-KANABEC- KANDIYOHI-LAC QUI PARLE-MARTIN-MCLEOD-MEEKER-MILLE LACS- MORRISON-NICOLLET-POPE-REDWOOD-RENVILLE-SHERBURNE-SIBLEY- STEARNS-STEVENS-SWIFT-TODD-WATONWAN-WRIGHT-YELLOW MEDICINE. WI...WIND CHILL ADVISORY FROM MIDNIGHT TONIGHT TO 12 PM CST WEDNESDAY FOR BARRON-CHIPPEWA-DUNN-EAU CLAIRE-PEPIN-PIERCE-POLK-RUSK- ST. CROIX. && $$ RAH/MDB