Billings, Montana

• Areas of fog through this morning, dense at times. Prepare for reductions to visibility.
• High confidence for widespread precipitation later today through Monday. Snowfall in the Absaroka/Beartooths and Bighorns and rain across the lower elevations. Record daily precipitation amounts for the month of November possible for some locations.

- Windy conditions on Monday, gusts 25 to 45 mph. A few gusts of
  50 mph or higher in Southeast Montana and Northern Wyoming.

Today through Saturday

Fog... The combination of low dewpoint depressions, light winds, and low level inversions will create conditions favorable for the formation of fog across the region this morning. Expect reductions to visibility and use caution while traveling. Fog or low level clouds are expected to remain throughout the day Sunday.

Low Elevation Rain... The 500 mb wave that will bring our upcoming system is currently just off the west coast. This trough is expected to split as it moves inland. At the surface, a Colorado Low will form bringing strong southerly winds up the plains advecting copious Gulf moisture. Ensemble systems are forecasting impressive PWAT values 250-300% of normal. The chance of precipitation increases across the lower elevations west of Billings this afternoon before spreading across the region through the late afternoon and evening. Moderate to heavy rainfall is expected south and east of Billings where there is a 40-80% chance of getting greater than 1 inch of rainfall. Chance for greater than 2 inches decreases to the 20-50% range. With rainfall potential this high, 24 hour precipitation records for the month of November are possible. Locations east of Billings will see easterly winds gusting into the 15-25 mph range this afternoon.

Mountain Snow... Snow is expected to begin to fall in the Absaroka/Beartooth mountains this afternoon before increasing in intensity this evening through Monday morning. North and west facing slopes can expect the greatest snowfall amounts with little accumulation expected in Cooke City. The potential for greater than 12 inches of snow are limited to the highest peaks on favored slopes. Snow accumulations are expected to wait until Sunday night for the Bighorns and increase in intensity Monday morning. There is a 40-80% chance of receiving greater than 6 inches of snow. Falling snow and winds gusting into the 40s mph will likely lead to visibility reductions and difficult travel conditions. A winter storms watch has been issued for the Northern Big Horns from 9 Pm this evening to 9 pm Monday evening due to the combination of moderate to heavy snowfall and strong winds. Snow levels have been trending down with both the Absaroka/Beartooths and Bighorns seeing snow levels in the 5,000-5,500 ft range putting places such as Red Lodge and Story in play. The chance of snow is expected to come to an end Monday evening.

Wind... A cold front will move across the region Monday increasing winds out of the north. Strong 700 mb winds are expected to bring winds gusting into the 30s mph and low 40s mph for most of the region. Locations along the Dakotas border and Sheridan County WY have the best chance of seeing wind gusting over 50 mph with 50-90% chances for these areas. Winds are expected to begin to decrease Monday evening and further decrease overnight.

Long Term... Tuesday through the end of the week is currently not expected to bring significant weather. Temperatures are expected to remain in the 50s with minimal chance for precipitation. Torgerson

Areas of IFR/LIFR will be common across the forecast area due to stubborn stratus ceilings and fog. Patchy freezing drizzle cannot be ruled out through the morning, but the chance is too low to include in TAFs at this time. Confidence is low regarding ceilings and suspect sites see significant changes at times through 18Z. We may see a period of MVFR/VFR briefly at some sites in the west (ie KLVM, KBIL) around midday before precipitation moves in late in day reducing flight rules again after 23Z. Mountains will be obscured through the period. Winds will generally be light and variable across the region. BT

    Tdy Mon     Tue     Wed     Thu     Fri     Sat
-------------------------------------------------------
BIL 047 041/054 033/058 035/054 033/058 034/057 035/055
    9/W +8/R    00/U    00/B    00/B    11/B    31/U
LVM 047 033/048 026/057 031/053 028/054 027/053 026/051
    8/W +5/O    00/B    00/B    01/B    11/B    40/U
HDN 052 037/052 025/060 027/056 025/058 028/058 032/056
    7/W ++/R    00/U    00/B    00/B    11/B    31/U
MLS 054 041/049 030/056 031/053 029/054 032/055 035/053
    8/W ++/R    00/U    00/B    00/B    01/U    21/B
4BQ 058 041/047 031/055 031/054 030/056 033/057 036/051
    9/W 9+/R    20/U    00/B    00/B    01/U    32/W
BHK 058 040/051 027/052 027/054 026/054 028/055 030/051
    3/W ++/R    20/U    00/B    00/B    00/B    21/N
SHR 051 032/046 025/059 028/055 026/058 028/058 030/054
    5/W +9/R    10/U    00/B    00/U    11/U    32/W

MT

Dense Fog Advisory in effect until noon MDT today FOR ZONES 29>33-36-37-57-58-138-173-235.

Winter Storm Watch in effect from this evening through Monday evening FOR ZONE 171.

WY

Dense Fog Advisory in effect until noon MDT today FOR ZONE 199.

Winter Storm Watch in effect from this evening through Monday evening FOR ZONE 198.