A HIGH WIND WARNING has been issued for the Rocky Mountain Front and the East Glacier area into Friday morning.
A chinook wind and chinook arch cloud formation are likely over the next several days. A chinook wind is downsloping wind from the Continental Divide that warms as it descends. This pattern typically creates a chinook arch cloud that forms above or just east of the Continental Divide. These cloud formations (mountain wave clouds) can create some beautiful sunsets. In this setup, there usually is a very strong wind across the plains and near the east side of the Divide as well. Areas that are not windy in this setup usually include the valleys of western Montana like Helena, Bozeman, Missoula and Kalispell. Thursday will be partly to mostly cloudy and windy especially on the Divide and across the plains. Temperatures will inch their way up into the 50s for most. Friday will be mostly cloudy with strong wind again across the plains and in the mountains. There will not be much wind in the valleys or west of the Continental Divide. Highs will be in the 50s. This weekend does not look bad if you can tolerate the wind. For both Saturday and Sunday, skies will be partly to mostly cloudy but it will be dry. Highs will be in the 50s to around 60. Average wind speeds during the day will range from between 20-40mph. There will be gusts up over 60mph especially along the Rocky Mountain Front. Halloween is Monday and a new storm will move in with some mixed rain and snow showers in the lower elevations and snow in the mountains. Highs will be in the 40s and 50s which is not bad. What will be bad is the wind and it should affect most of the state including the western valleys. Make sure some of those little trick or treaters do not get blown away! Colder air and the chance of snow will move into the state for the beginning of November. There could be several inches of accumulation in the lower elevations beginning Tuesday and continuing through Wednesday. It's a good thing Halloween is not one of those two days...
Curtis Grevenitz
Chief Meteorologist
