wxgeek's weather-High Winds Possible Tues Night and Wed

Update Tue Oct 16

Upper level system and cold front currently moving through the northern Rockies. Before system arrives, we will see warm temps and breezy southwest winds. Very close to Red Flag conditions today across much of CO as RH values below 15% and winds will increase through the day. Currently a High Wind Warning in effect for the northern foothills of Boulder and Larimer counties through midnight tonight, and a Fire Weather Watch for most of eastern CO below 6000 ft for Wednesday. I would expect the high wind warning to be extended into Wednesday for much of the foothills. Fire danger will remain very high on Wednesday as well.

Cold front is expected to move through eastern CO this evening, which will bring much cooler temps and an increase in RH values tonight. Snow above 6500-7500 ft for the northern and central mountains tonight, maybe 1-3 inches possible. Snow only expected to make it east to the Front Range crest, so nothing outside of a few stray flakes expected in the foothills. West to northwest winds will increase tonight towards dawn as upper level jetstream moves into northeast CO. Amplified mountain wave expected to form overnight, so down-slope winds of 25-50 mph likely, with gusts to 65 mph possible, especially north of I-70. Strong west to northwest winds will continue all day on Wednesday, so a cool and windy day on tap for Wednesday with wind speeds in the 25-50 mph range possible all day long, and will likely persist into Wednesday night.

Winds expected to calm down on Thursday and temps begin to warm. Dry and mild conditions expected across the state into the weekend. Models now indicate these dry and mild conditions also expected to persist into next week as well. Precip does not look likely or abundant through the end of October at this point, which would make this a very dry October, possibly one of the driest on record for the foothills and Plains. Hopefully the long range models are incorrect.
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"Climatology is what you expect, Weather is what you get".

"It is better to be roughly right than precisely wrong".

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Another beautiful day across the state today with temps above seasonal averages in most locations and abundant sunshine. A weak upper trough will pass to the north of us tonight, so some mid and high clouds along with some breezy westerly winds.

A stronger system from the Pacific Northwest will move into the northern Rockies on Tuesday, and will drag a cold front into northern CO Tuesday night. Some precip is possible Tuesday night across the northern and central mountains mostly north of I-70. Some showers will be possible across the foothills and Urban Corridor as well, but any precip would be very light. Maybe 1-3 inches of snow possible for the mountains, with the snow level around 5500-6500 ft near the WY border, and 6500-7500 ft near I-70. System moves east Wednesday so precip should end by early Wednesday morning. Cold front will bring much cooler temps Tuesday night and Wednesday. Although temps will be cooler, the strong west to northwest winds will increase fire danger over the foothills and Plains as grasses have dried out significantly.

The primary impact from this system will be the potential for a high wind event Tuesday night into Wednesday night. Strong northwest jetstream winds aloft will move into northern CO Tuesday night on the back side of upper trough and will persist into Wednesday evening/night. Wind speeds aloft at jetstream level will be over 130 mph, with winds at mountain top level in the 50-75 mph range. It is likely an enhanced mountain wave will form which will enhance winds below mountain top level. Currently no watches or warnings out, but that may change in the next 24 hours. I would expect surface winds in the 25-50 mph range along the foothills Tuesday night into Wednesday evening, with some gusts to 65 mph possible at higher elevations east of the Divide. Winds should die down by Thursday morning, with temps beginning to rebound.

Late this week into the weekend should be dry with temps back to or above seasonal norms. Long range models indicate a broad upper trough will develop over the western and central U.S. early next week, which will allow a cold front to drop south across CO and bring a chance for snow Tuesday and Wednesday next week. Currently does not look like significant amounts, but certainly much colder temps until late next week when dry and mild conditions return.
_________________
"Climatology is what you expect, Weather is what you get".

"It is better to be roughly right than precisely wrong".

Bump for Wed Oct 17 update