000 FXUS65 KMSO 112130 AFDMSO WESTERN MONTANA AND NORTH CENTRAL IDAHO FORECAST DISCUSSION NATIONAL WEATHER SERVICE MISSOULA MT 230 PM MST MON MAR 11 2002 .SHORT TERM...VERY MOIST PACIFIC SYSTEM CONTINUES IT TRACK EAST OVER THE FORECAST AREA THIS AFTERNOON THROUGH TONIGHT. WARM FRONT PRECIPITATION HAS SPREAD OVER ALL BUT LEMHI AND BUTTE/PINTLAR REGIONS THIS AFTERNOON. GOOD PACIFIC FETCH OF MOISTURE TO REMAIN OVER THE AREA THROUGH THE NIGHT...THEN SAG SOUTH TUESDAY AS THE 130- 150KT JET MOVES SOUTH. MODEL QPF IS IN EXCESS OF 1.5 INCHES OVER THE CENTRAL AND NORTHERN ZONES BY TUESDAY MORNING. WITH FREEZING LEVELS AS HIGH AS THEY ARE (AROUND 6000 FEET) THIS AFTERNOON...THE SNOW TO WATER EQUIVALENT IS BETWEEN 5-8 TO 1...BUT STILL RESULTING IN HEAVY SNOW CRITERIA IN THE HIGHEST MOUNTAINS. THE MODELS HAVE SLOWED THE SOUTHERLY PROGRESSION OF THE COLD FRONT OVERNIGHT. THE CLEARWATER AND BITTERROOT/SAPPHIRE MOUNTAINS WILL LIKELY BE SNOWING ABOVE 5000 FEET THROUGH TUESDAY MORNING. WILL THEREFORE EXTEND THAT WARNING UNTIL MID MORNING TUESDAY. SNOW TOTALS OF 8 TO 14 INCHES A GOOD BET WITH NEAR 2 FEET IN THE HIGHEST PEAKS NOT OUT OF THE QUESTION. GOOD SOUTHERLY FLOW OVER THE AREA WILL BECOME WEST AND NORTHWEST OVERNIGHT...WITH WINDS DECREASING DURING THE AFTERNOON AND EVENING TUESDAY FROM NORTH TO SOUTH. WINDS IN THE CAMAS PRAIRIE ARE ALREADY GUSTING TO OVER 40 MPH THIS AFTERNOON. 850 MB WINDS WILL REMAIN STRONG UNTIL AROUND MIDNIGHT. WILL THEREFORE ISSUE A WIND ADVISORY FOR THIS EVENING FOR THE CAMAS PRAIRIE. ZONAL FLOW OVER THE AREA TUESDAY NIGHT AND WEDNESDAY WILL KEEP SCATTERED MOUNTAIN SNOW WITH VALLEY RAIN SHOWERS. WEDNESDAY NIGHT ANOTHER UPPER TROUGH WILL MOVE OVER THE REGION FOR MORE SNOW OVER THE AREA WITH SHOWERS FOR THURSDAY WITH TEMPERATURES RETURNING TO A COOLER THAN NORMAL REGIME. MEAD .LONG TERM...PROGS FAIRLY CONSISTENT AT THE START OF THE EXTENDED PERIOD. ALL SHOW A STRONG SHORTWAVE OR CUTOFF LOW DROPPING SOUTH ALONG THE BC COAST FRI WITH AN ACCOMPANYING ARCTIC FRONT. MODELS DIVERGE THEREAFTER IN POSITION AND STRENGTH OF THE SYSTEM. MOST MODELS (MRF/CMC/NOGAPS) KEEP A DEEP CUTOFF LOW JUST OFF THE WA COAST WITH THE ARCTIC BOUNDARY OVER WRN MT. THIS WOULD SET UP HEAVY OVER- RUNNING SNOWS FOR THE NRN ROCKIES. THE AVN IS MORE PROGRESSIVE IN TAKING THE TROF THROUGH. THE EURO TAKES A CUTOFF DOWN INTO THE GREAT BASIN. ALL SOLUTIONS OPEN THE DOOR FOR ARCTIC AIR TO POUR ACROSS MONTANA THIS WEEKEND. WILL BE GOING WITH A BLEND OF SOLUTIONS AND KEEPING CHC OF SNOW FOR THE WEEKEND AND DRASTICALLY UNDER-CUTTING MOS TEMPS THROUGH EARLY NEXT WEEK. WRIGHT .MSO...HEAVY SNOW WARNING CONTINUES TONIGHT FOR MTZ001-002-004- 043... ...HEAVY SNOW WARNING TONIGHT THROUGH TUESDAY MORNING FOR MTZ006 AND IDZ005-006... ...WIND ADVISORY FOR THIS EVENING IDZ007-008... ...7-DAY SPOT TEMPS AND POPS... LIB EEE 026/038 022/035 020/032 27+44453 SSEE 017/030 016/026 009/023 005/021 3235543333 FCA EEE 032/042 025/038 024/034 27834353 SSEE 017/029 016/028 009/022 004/020 3235543333 POL WEC 035/045 028/042 028/038 27854353 SSEE 018/031 018/029 011/024 007/022 3235543333 MSO WEE 033/044 027/039 024/036 27864353 ESJE 016/033 014/028 007/024 005/020 3233553333 HMM REE 037/047 029/042 028/038 27864343 ESJE 018/034 015/029 010/025 006/021 3233553333 BTM WEC 032/042 015/035 013/035 27363332 ESJE 016/030 015/022 904/017 910/018 3233554333 ORO WEE 040/051 035/046 033/044 27874453 EOJE 030/042 029/041 025/035 020/035 3233344333 GRV WEE 037/046 033/043 031/042 27874453 ESJE 025/035 022/030 018/028 016/026 3233344333 SMN WEE 033/046 025/038 019/035 27774332 ESSE 017/034 015/026 901/019 905/018 3233455333