Issued by NWS Duluth, MN
000 FXUS63 KDLH 071604 AAA AFDDLH AREA FORECAST DISCUSSION...UPDATED NATIONAL WEATHER SERVICE DULUTH MN 1004 AM CST FRI NOV 7 2008 .UPDATE... FOCUS FOR THIS MORNING UPDATE IS ON PRECIPITATION CHANGEOVER FROM RAIN TO SNOW OVER THE NEXT 24 HOURS. A FEW BANDS OF PRECIPIATIION CONTINUE TO MOVE NORTHWEST THROUGH THE NORTHERN TIER...WHILE ADDITIONAL BANDS SCOOT NORTH IN WISCONSIN AHEAD OF THE SURFACE LOW. TEMPERATURES IN THE FORECAST AREA STILL REMAIN WARM ENOUGH TO SUPPORT RAIN THROUGH THE MORNING AND EARLY AFTERNOON HOURS. WE ARE CONTINUING TO MONITOR AREAS IN NORTHWEST WISCONSIN...ALONG THE SOUTHERN TIER OF BURNETT..WASHBURN...AND SAWYER COUNTIES...AS LOCATIONS JUST TO THE SOUTH...INCLUDING EAU CLAIRE AND UP TO RICE LAKE HAVE BEEN WAFFLING BACK AND FORTH BETWEEN RAIN AND SNOW. COLDER TEMPERATURES ARE WRAPPING AROUND THE DEEP LOW PRESSURE SYSTEM IN SOUTHERN MINNESOTA. BUT...WINDS ARE EXPECTED TO REMAIN EASTERLY IN THESE ABOVE MENTIONED COUNTIES...WHICH WILL KEEP THE COOLER AIR TO THE SOUTH...UNTIL WINDS TAKE ON A MORE SOUTHERLY TRAJECTORY. THIS APPREARS TO OCCUR AFTER 2100 UTC/300 PM CST...AND SO WE HAVE INTRODUCED OCCASIONAL SNOW IN THESE AREAS IN THE LATE AFTERNOON...WITH THE PREDOMINANT PRECIP TYPE AS RAIN...UNTIL AFTER 0000 UTC. CONCERNING AREAS FURTHER WEST...BEMIDJI HAS ALSO BEEN TOGGLING BETWEEN RAIN/DRIZZLE/SNOW THIS MORNING...AND THIS IS THE SECOND AREA THAT WILL SEE A CHANGEOVER TO SNOW THIS AFTERNOON. WE HAVE UPDATED THE ZONES TO INDICATE A POTENTIAL CHANGEOEVER IN THE INTERNATIONAL FALLS VICINITY AFTER 1800 UTC...WITH WINDS EXPECTED TO BECOME NORTHERLY...AND COMMENCING COLD AIR ADVECTION. FORECAST SOUNDINGS INDICATE THAT MUCH OF THE WESTERN TIER OF THE AREA...FROM THE BRAINERD LAKES NORTH TO GRAND RAPIDS WILL REMAIN RAIN THROUGH 0000 UTC/600 PM CST...THOUGH A FEW SNOW FLAKES DURING THE EVENING COMMUTE ARE NOT OUT OF THE QUESTION WITH 850/925 TEMPS BEING COLD ENOUGH. WINDS WILL ALSO BECOME RATHER GUSTY ON THE BACK SIDE OF THE LOW PRESSURE...WHICH WILL REDUCE VISIBILITIES IN AREAS OF SNOW...EVEN THOUGH SNOW IS EXPECTED TO BE LIGHT. REST OF THE FCST UNCHANGED FOR NOW. && .PREV DISCUSSION... /ISSUED 342 AM CST FRI NOV 7 2008/ DISCUSSION...SATELLITE IMAGERY SHOWING AN IMPRESSIVE SYSTEM WOBBLING OVER SW MN. MSAS SFC PRESSURE MINIMUM HOLDING AT 997 MB OVERNIGHT. THE NAM/GFS/RUC ALL SUGGEST THE SFC LOW CIRCULATION BROADENS OVER EC MN AS THE CEN PRESSURE INCREASES TO 1003 MB BY 15Z. ATTM...THIS APPEARS TOO AGGRESSIVE IN FILLING THE LOW AND EXPECTING A SLIGHTLY SLOWER EWRD TRACK THAN MODELS SHOW. BANDS OF RAIN WILL CONTINUE TO LIFT NORTH AND WEST AROUND THE SYSTEM AND OVER THE FA TODAY...KEPT LIKELY TO DEF POPS FOR MOST AREAS...WITH SCT SHRA IN THE TIP OF THE MN ARROWHEAD. FORECAST CHALLENGE IN PCPN TYPE THIS AFTRN THROUGH SATURDAY AFTRN. THE COLD CORE ALOFT AND ASSOCIATED LOWEST THICKNESSES ARE FOUND TO THE SOUTH OF THE SFC LOW AS RELATIVELY WARMER AIR HAS WRAPPED AROUND THE NRN SIDE OF THE SYSTEM...OVER THE WRN GRT LAKES REGION. THICKNESS FALLS...AND SUB-ZERO 850 TEMPS FOUND ON THE BACK SIDE OF THE SYSTEM ARE PROGGED TO SHIFT EAST INTO THE WRN THIRD OF THE FA THIS AFTERNOON AS SYSTEM PROGRESSES SLOWLY E. THIS WILL RESULT IN A PERIOD OF SN MIXING WITH THE RA IN THE WRN AREAS...BEFORE THE LOW LVLS COOL ENOUGH TO SUPPORT ALL SN. HOWEVER...SOME UNCERTAINTY IN SPECIFIC TIMING OF RA TO SN TRANSITION. SUSPECT MODELS ARE ADVANCING SYSTEM E TO QUICKLY. IF SO...RA/SN PHASE CHANGE WILL BE LATER INTO THE EVENING FOR THE WRN AREAS. OVERNIGHT...MOST MN LOCATIONS CAN EXPECT TO SEE RA IN THE EVENING...TRANSITIONING TO A RA/SN MIX OR ALL SN AFTER 06Z. AREAS NEAR LAKE SUPERIOR AND IN NW WIS EXPECTED TO REMAIN WARM ENOUGH FOR RA THROUGH MUCH OF THE NIGHT...POSSIBLY MIXING WITH A FEW SNOW FLAKES AROUND DAY BREAK SAT. AREAS ALONG THE SOUTH SHORE WILL TRANSITIONING TO SN SAT AFTRN...WITH A FEW INCHES OF ACCUMULATION POSSIBLE LATE SAT INTO EARLY SUN. ELSEWHERE...SN ACCUMULATION THROUGH THIS WEEKEND WILL BE MINIMAL. MOST AREAS CAN EXPECT A DUSTING...TO AROUND AN INCH. AVIATION...MAINLY MVFR-VFR CONDITIONS EARLY THIS MORNING WILL DETERIORATE TO PRIMARILY IFR-MVFR BY 12Z...AND THEN PERSIST THROUGH MUCH OF THE DAY AS AN INTENSE AREA OF LOW PRESSURE SLOWLY PUSHES EAST ACROSS MINNESOTA. AREAS OF DRIZZLE AND ASSOCIATED LOW STRATUS WILL BE POSSIBLE...ESPECIALLY FROM KDLH AND POINTS NORTH...ALONG THE NORTH SHORE THROUGH THIS MORNING. AREAS OF RAIN WILL THEN BECOME MORE COMMON...FROM WEST TO EAST...BETWEEN 12Z-18Z. CEILINGS AND VSBYS MAY ONCE AGAIN LIFT A BIT DURING THE EARLY AND MID AFTERNOON...BEFORE LOWERING AGAIN DURING THE EVENING. RAIN COULD BECOME MIXED WITH SNOW AS EARLY AS 18Z FROM KINL SOUTH TO KBRD...BUT WILL LIKELY REMAIN ALL LIQUID THROUGH AT LEAST 06Z SATURDAY SOUTH AND EAST OF KDLH. WINDS WILL SHIFT TO THE NORTH AND NORTHWEST BY FRIDAY AFTERNOON...WITH SOME INCREASE IN SURFACE WIND SPEEDS...ALTHOUGH THE STRONGEST WINDS WILL REMAIN JUST SOUTH OF OUR AREA. && POINT TEMPS/POPS... DLH 44 31 37 21 / 70 70 40 10 INL 39 27 31 19 / 80 60 30 10 BRD 42 29 33 22 / 80 60 30 10 HYR 46 33 37 22 / 70 70 60 10 ASX 46 35 37 25 / 70 70 70 40 && .DLH WATCHES/WARNINGS/ADVISORIES... MN...NONE. WI...NONE. LS...NONE. $$ DONOFRIO/EOM