The big story this weekend is going to be the wind. The wind will increase as we go through tonight, with windy conditions (gusts over 60 mph) developing along the Rocky Mountain Front after midnight and breezy conditions (gusts up to 40 mph) persisting out across the plains. Along the Rocky Mountain Front and the Hi-Line west of I-15, it will be extremely windy tomorrow and Sunday as sustained wind speeds are going to be between 30 and 60 mph, and wind gusts up to 85 mph are possible. Along the immediate eastern slopes of the Rocky Mountain Front, gusts of 100+ mph are possible this weekend. A HIGH WIND WARNING is in effect for the Rocky Mountain and the western part of the Hi-Line from 2am Saturday until 12am Monday.
East of the Rocky Mountain Front, it will be gusty/windy tomorrow as sustained wind speeds are going to be between 15 and 35 mph, and wind gusts over 50 mph are possible. It is then going to be very windy on Sunday as sustained wind speeds are going to be between 20 and 45 mph, and widespread wind gusts of 50-70+ mph are expected. Wind damage, including downed power lines, flying debris, and broken branches are possible. There may also be areas of blowing dust around this weekend, especially on Sunday. A HIGH WIND WATCH is in effect for Cascade County, Judith Basin County, and Fergus County from 8am Saturday until 12am Monday; for southwestern Phillips County from 8pm Saturday until 9pm Sunday; and for the rest of central and north-central Montana from 3am Sunday until 12am Monday.
In the Helena Valley, it will just be breezy tomorrow as sustained wind speeds are going to be between 10 and 25 mph. It is then going to be windy on Sunday as sustained wind speeds are going to be between 15 and 35 mph, and gusts over 50 mph are possible.
Here is the detailed forecast:
It is also going to be mild this weekend as highs are going to be in the 50s and low to mid 60s in most locations. Tomorrow will be partly to mostly cloudy with some snow/rain along the Divide, a few scattered snow and rain showers around the Helena area, and a couple isolated rain and snow showers in north-central Montana as a disturbance passes through the state. A coating to a few inches of snow accumulation is possible in the mountains tomorrow. In the lower elevations, little to no snow accumulation is expected.
Sunday will also be partly to mostly cloudy and there will be some snow/rain along the Divide throughout the day. Some scattered rain and snow showers are also expected along the Hi-Line during the late afternoon and evening as a cold front begins to pass through our area.
Colder temperatures return for the beginning of next week as highs on Monday are going to be in the mid to upper 30s and low to mid 40s and highs on Tuesday are going to be in the 30s and low 40s. There will also be some scattered snow and rain showers around on these two days, especially in the mountains and along the Hi-Line, as a couple disturbances pass through the state. It is also going to be partly cloudy and windy on these two days as sustained wind speeds are going to be between 15 and 35 mph, and wind gusts over 50 mph are possible.
Some more scattered rain and snow showers are possible on Wednesday, especially later in the day, as another storm system begins to approach the state. It is also going to be windy and warmer on Wednesday as sustained wind speeds are going to be between 15 and 35 mph, and highs are going to be in the 40s.
Rain and snow showers are expected on Thursday and Friday as this storm system passes through the state. It is also going to be partly to mostly cloudy on these two days. It will continue to be windy on Thursday as sustained wind speeds are going to be between 15 and 35 mph, but the wind will weaken some for Friday (sustained wind speeds between 10 and 20 mph). The temperatures are also going to cool down some between Thursday and Friday as highs on Thursday are going to be in the mid to upper 40s and low to mid 50s, and highs on Friday are going to be in the 30s and low 40s.
