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Extreme heat to snow this holiday weekend

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BOZEMAN – Extreme weather event to impact Montana this holiday weekend.

It begins with extreme heat on Saturday. Forecast highs both west and east of the divide are mostly in the low to upper 90s and a few low 100s are possible. Numerous record highs are likely across the state.

The combination of extreme heat, relative humidity values below 20%, and surface winds increasing 10 to 20 mph and gusting at times over 30 mph will create extreme and erratic fire behavior Saturday afternoon and evening. Like the event on Wednesday.

A RED FLAG WARNING is up across the state of Montana Saturday noon to midnight. During red flag warning events human caused fires are the greatest concern. Small fires can grow out of control in just a few minutes.

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Now here comes the crazy part of the forecast. Starting Sunday, the high-pressure ridge will collapse, and a very cold Canadian cold front will drop southward into Montana. Temperatures will likely stay in the 80s to low 90s Sunday but will fall rapidly on Monday.

Forecast models show the core of the colder air digging into SW Montana Monday afternoon. Forecast highs for Monday will vary greatly but are useless as temperatures will continue to fall hour by hour Monday with the coldest air reaching our region by Monday afternoon.

Temperatures are likely to fall below to well below freezing by Tuesday morning. I recommend covering all flowers and gardens Monday through Wednesday to protect them from freezing.

The other hazard with this abrupt pattern change will be mountain snow. Snow levels could fall down as low as 5,500’ at times Monday afternoon and evening. Minor accumulations are likely for higher valleys and above 7,000’ look for several inches or more.

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Those of you planning to be in the backcountry bowhunting or hiking should be prepared for a significant temperature drop, gusty winds, and wet conditions Monday through Wednesday.