728 FXUS63 KMPX 042358 AAA AFDMPX AREA FORECAST DISCUSSION...UPDATED NATIONAL WEATHER SERVICE TWIN CITIES/CHANHASSEN MN 558 PM CST TUE NOV 4 2014 .SHORT TERM...(THIS EVENING THROUGH WEDNESDAY) ISSUED AT 409 PM CST TUE NOV 4 2014 FORECAST CONCERNS ARE TIMING OF NEXT PRECIPITATION EVENT AND PRECIPITATION TYPE/AMTS. A STRONG STORM SYSTEM MOVING ACROSS THE PACIFIC NW...AND INTO THE NORTHERN ROCKIES WILL BE THE MAIN PLAYING IN THE SHORT TERM AS MOISTURE RAPIDLY SPILLS ACROSS THE NORTHERN PLAINS AND INTO THE UPPER MIDWEST AFTER MIDNIGHT. THIS SYSTEM IS A TYPICAL ALBERTA CLIPPER WHICH HAS LIMITED MOISTURE...BUT STRONG FORCING IN THE MID LEVELS OF THE ATMOSPHERE. THIS WILL LEAD TO A BRIEF/CONCENTRATED HIGH QPF EVENT IN A SMALL BAND IN A 12 TO 24 HR TIME PERIOD. USUALLY THESE TYPE OF PRECIPITATION EVENTS ARE FASTER THAN MODEL INDICATE...SO PRECIPITATION WILL LIKELY DEVELOP PRIOR TO SUNRISE ACROSS WC/CENTRAL MN. ALTHOUGH TYPICALLY AN ALBERTA CLIPPER TYPE STORM SYSTEM COMES DURING WINTER...AND NOT SO MUCH LATE FALL...MOST OF THE PRECIPITATION SHOULD BE IN THE FORM OF RAIN. IN ADDITION... THERMAL PROFILES REMAIN RELATIVELY WARM DURING MOST OF THE EVENT. ONLY A SMALL WINDOW OF OPPORTUNITY DOES PORTIONS OF CENTRAL MN/WC WI IS COLD ENOUGH FOR SNOW...OR A MIXTURE OF SNOW/RAIN. THIS WILL LIMIT ANY SNOWFALL ACCUMULATIONS...AND MOSTLY FOR GRASSY SFC/S. THERE REMAINS SEVERAL PROBLEMS WITH PRECIPITATION TYPE/COVERAGE/ LOCATION WITH THIS SYSTEM. FIRST...THE BEST FORCING DEVELOPS EARLIER THAN WHEN THE DEEPER MOISTURE ARRIVES. THIS WILL CREATE PROBLEMS WITH SATURATION AND/OR PRECIPITATION TO DEVELOP VS. VIRGA. HOWEVER...SOMETIMES THE FORCING ALONE CAN BE STRONG ENOUGH TO INDUCE BETTER MIXING IN THE ATMOSPHERE. ALSO...PLACEMENT OF THE STRONGEST FORCING 24 HRS AHEAD REMAINS PROBLEMATIC IN TERMS OF LOCATION. ANY DEVIATION 50-100 MILES TO THE NORTH OR SOUTH OF THIS FRONTOGENETICAL BAND WILL CREATE PROBLEMS IN TERMS OF THE DRY/WET WEATHER WILL DOMINATE. THE BEST SCENARIO IS TO HOLD ONTO THE HIGHEST POPS/QPF ALONG AND NORTH I-94...WITH MINOR SNOWFALL ACCUMULATIONS FROM NORTH OF LITTLE FALLS TO MORA IN MINNESOTA...AND NORTH OF LUCK AND RICE LAKE IN WEST CENTRAL WISCONSIN. TEMPS WILL REFLECT THE COLDER WET SNOW AND/OR RAIN IN CENTRAL MN WHICH WILL LIKELY REMAIN IN THE 30S...WITH A SHARP CONTRAST TO THE SOUTH NEAR THE IOWA BORDER WHERE 50S WILL BE COMMON. .LONG TERM...(WEDNESDAY NIGHT THROUGH TUESDAY) ISSUED AT 409 PM CST TUE NOV 4 2014 BY WEDNESDAY NIGHT...THE CLIPPER SYSTEM MENTIONED IN THE SHORT- TERM WILL BE ON ITS WAY TO THE EAST OF THE FORECAST AREA. THE WRAP AROUND PRECIP SHOULD PASS THROUGH EASTERN MN AND WESTERN WI BETWEEN 00-06Z...SO WE MIGHT BE HOLDING ONTO POPS/WX A LITTLE TOO LONG BY KEEPING A MENTION IN THE FORECAST UNTIL THURSDAY MORNING. CERTAINLY THE LIGHT TO MODERATE RAIN OR SNOW WILL BE OUT OF THE FORECAST AREA BY 12Z THURSDAY...BUT THE QUESTION IS HOW LONG TO HANG ONTO THE VERY LIGHT SNOW IN THE POST-FRONTAL AIR MASS AS THE UPPER TROUGH SWINGS THROUGH THE FORECAST AREA THURSDAY MORNING. THE TIMING OF THE FRIDAY EVENING/NIGHT COLD FRONT IS MORE CLEAR CUT TODAY WHEN COMPARED TO YESTERDAY. THERE IS GOOD AGREEMENT BETWEEN THE NAM/GFS/ECMWF. IN TERMS OF LIQUID WITH THE SYSTEM...THE 04.12Z/18Z NAM SEEMS OVERDONE WITH HOW FAR SOUTH IT BRINGS THE PRECIP INTO THE FORECAST AREA. THE FORCING IS JUST TOO FAR NORTH TO GET MUCH LIQUID TO THE GROUND IN SOUTHERN MN. THE GFS/ECMWF ARE PRETTY CLOSE TO ONE ANOTHER WITH THEIR SOLUTIONS AND WOULD KEEP MOST OF THE LIGHT RAIN/SNOW MIX NORTH OF THE I-94 CORRIDOR. THIS COLD FRONT ARRIVES IN TIME FOR THE WEEKEND AND IS COLDER THAN THE FRONT THAT CAME THROUGH YESTERDAY AND THE ONE EXPECTED WITH THE CLIPPER TOMORROW. IT WILL BE A STRUGGLE TO HIT 40 ON BOTH SATURDAY AND SUNDAY...WITH MANY LOCATIONS REMAINING IN MID 30S. NEXT WEEK SHOULD BE EVEN COLDER THAN THE WEEKEND...ESPECIALLY IF YOU PUT MORE STOCK INTO THE ECMWF LONG RANGE SOLUTION. CONSIDERING THE FORECASTS OVER THE PAST 24 HOURS...AT BEST THE ECMWF AND ECMWF ENSEMBLE ARE FORECASTING TEMPS 10 TO 15 DEGREES BELOW NORMAL...AT ITS COLDEST...IT'S 2-3 STANDARD DEVIATIONS BELOW NORMAL. THE LOWEST 850MB TEMPS HAVE BEEN PROGGED AT -16C TO -19C OVER THE LOCAL AREA. THE RESULT AT 2 METERS ARE FORECAST LOW TEMPS OF 6...12...5 FOR WEDNESDAY...THURSDAY...AND FRIDAY RESPECTIVELY OFF THE 04.12Z ECMWF. THE NAEFS AND GEFS AREN'T QUITE AS COLD WITH THE AIR MASS AND GIVE MN/WI A LITTLE MORE OF A GLANCING BELOW. THEY STILL INDICATE WELL BELOW NORMAL TEMPS. CONFIDENCE IN COLDER THAN NORMAL WEATHER NEXT WEEK IS CURRENTLY AS ABOUT AS HIGH AS IT GETS 6-10 DAYS OUT GIVEN OUR TRACK RECORD OVER THE PAST YEAR...THE AGREEMENT OF OPERATIONAL OUTPUT AND ENSEMBLE GUIDANCE AND THE DOWNWARD TREND OF THE AO AND PNA. ONLY THING THAT WOULD TAKE OUR CONFIDENCE IN WELL BELOW NORMAL TEMPS ANY HIGHER WOULD BE IF THERE WAS SOME SNOW ON THE GROUND. THE 04.12Z ECMWF HAS ALSO TAKEN CARE OF THAT MONDAY NIGHT INTO TUESDAY...BUT WE'LL LET LATER SHIFTS HANDLE THAT NICE LITTLE SNOW STORM. THE COMPLETELY INFALLIBLE 160-HR SNOW FORECAST OFF THE 12Z ECMWF...7-10" LOCALLY MONDAY NIGHT INTO TUESDAY. && .AVIATION...(FOR THE 00Z TAFS THROUGH 00Z WEDNESDAY EVENING) ISSUED AT 558 PM CST TUE NOV 4 2014 STRATUS DECK ACROSS MOST OF NORTHERN MN/WI WILL ROTATE EAST/SOUTHEAST THIS EVENING. MOST OF THE TAF SITES ARE CURRENTLY AFFECTED BUT SKIES WILL CLEAR LATER THIS EVENING. INCREASING MID/HIGH LEVEL CLOUDS OVERNIGHT WILL LOWER QUICKLY WEDNESDAY MORNING TO MVFR CONDITIONS OVER CENTRAL MN. CIGS SHOULD REMAIN VFR FURTHER SOUTH THROUGH MUCH OF THE DAY. P-TYPE WILL BE TRICKY NORTH OF AXN/STC...BUT ALL MPX TAF SITES WILL LIKELY BE MAINLY RAIN THROUGH THE DAY BEFORE COLDER AIR ARRIVES BEHIND THE LOW DURING THE EVENING WHEN A PERIOD OF LIGHT SNOW IS POSSIBLE. KMSP...HIGH CONFIDENCE ON VFR CONDS THRU 12Z WED. CIGS WILL BEGIN TO LOWER AFT 12Z...WITH MVFR CIGS POSSIBLE AND -RA BEGINNING BETWEEN 15-18Z. SOME SNOW MAY MIX WITH THE RAIN BY WEDNESDAY EVENING WITH LITTLE OR NO ACCUMULATION EXPECTED. GUSTY W/WNW WINDS WILL DECREASE QUICKLY THIS EVENING AND BECOME VARIABLE OVERNIGHT AS THE LOW APPROACHES. WINDS WILL INCREASE NORTHWEST AGAIN TOMORROW AFTERNOON AS THE LOW PUSHES EAST. /OUTLOOK FOR KMSP/ THU...VFR. POSSIBLY MVFR CIGS EARLY. WNDS NW 15G20 KTS. FRI...MVFR CONDS POSSIBLE WITH -RA. CHC OF -SN LATE. WNDS S 10 KTS. SAT...MVFR CONDS POSSIBLE EARLY WITH -RASN. WNDS NW 15G25KTS. && .MPX WATCHES/WARNINGS/ADVISORIES... MN...NONE. WI...NONE. && $$ SHORT TERM...JLT LONG TERM...CLF AVIATION...BORGHOFF