An upper level ridge located over southwestern Wyoming/northwestern Colorado/northeastern Utah is providing us with southerly to southwesterly flow aloft, and this flow aloft is going to bring some monsoonal moisture into our area over the next few days. For this evening and tonight, there are going to be scattered rain showers and isolated thunderstorms around. There are then going to be some scattered rain showers and isolated thunderstorms around tomorrow, tomorrow night, and Wednesday.
A lot of the precipitation we see over the next few days is going to be light to moderate in nature, but some heavier showers are possible. Heavy rainfall is also possible with any thunderstorms that develop. In general, most locations are going to receive between a tenth and a third of an inch of rainfall between this evening and Wednesday evening, although higher rainfall amounts are possible in locations that do see a few heavier showers and/or thunderstorms.
This monsoonal moisture is also going to provide us with more cloud cover as mostly cloudy skies are expected tonight; partly to mostly cloudy skies are expected tomorrow; and partly cloudy skies are expected tomorrow night. We are then going to have partly cloudy to mostly sunny skies on Wednesday.
Mostly sunny to sunny skies and mostly dry conditions are then expected Thursday, Friday, and this weekend as the upper level ridge flattens out causing the monsoonal moisture to remain to the south of Montana.
As we go through the next week, it is going to continue to be very warm/hot during the day as highs are generally going to be in the upper 80s and low to mid 90s. An Excessive Heat Warning also remains in effect for eastern Montana until 9pm on Thursday. In terms of the lows, it is going to be warm tonight as lows are going to be in the mid 60s in central Montana and the mid 70s in eastern Montana. It is then going to be mild tomorrow night and Wednesday night as lows are going to be in the upper 50s and low to mid 60s. Lows for Thursday night through Sunday night are then going to be more comfortable as lows are generally going to be in the 50s.
For a lot of this week, the wind is not going to be a huge issue. However, breezy conditions are expected Thursday afternoon/evening and Friday afternoon/evening as sustained wind speeds are going to be between 10 and 25 mph. Critical fire weather conditions are also possible on Thursday and Friday, since it is going to be hot, dry, and breezy.
Smoky/hazy skies are also expected for the foreseeable future in all of Montana due to wildfires burning locally and regionally. With this smoke/haze in the air, it is possible that the air quality may become unhealthy for sensitive groups at times, so if you are sensitive to increased particulates in the atmosphere, then you may want to try and limit your time outdoors. There is also an Air Quality Alert in effect for parts of Montana through at least 12pm Tuesday.