102 FXUS65 KBOU 140023 AFDBOU

Area Forecast Discussion National Weather Service Denver/Boulder CO 623 PM MDT Mon Apr 13 2026

.KEY MESSAGES...

- Critical fire weather conditions again today over the southern portions of the forecast area and the plains near the Wyoming border. Critical fire weather conditions to continue Tuesday, though will be limited to Lincoln County.

- Next weather system to bring cooler temperatures and a decent chance of precipitation to the forecast area Tuesday into early Wednesday. A few inches of snow for the higher mountains with slick travel possible over the higher passes mainly Tuesday night.

- Another storm system is possible for the forecast area Thursday night into Saturday.

- Elevated to critical fire weather conditions possible each afternoon through the week.

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.DISCUSSION /Through Monday/... Issued at 101 PM MDT Mon Apr 13 2026

Current water vapor imagery shows our next weather system is slowly progressing eastward into the Great Basin this afternoon in the form of an upper-level trough. Meanwhile, above normal temperatures and dry conditions are in place across the forecast area, with breezy surface winds bringing elevated to critical fire weather conditions across much of the forecast area. Today`s Red Flag Warning will remain in place through 8 PM this evening for areas along our northern and southern boundaries where relative humidity values ranging from the single digits to low teens are expected to coincide with southwest gusts around 30 mph through the early evening. Outside of the fire weather concerns, things are pretty nice across the forecast area, with afternoon temps expected to warm into the upper 60s to 70s across the plains, and 50s for the mountain valleys.

Expect clouds to increase through the night tonight as increasing southwesterly flow is expected to bring Pacific moisture into the region. We could start to see some light rain showers over the higher elevations this afternoon, but chances for snow showers will increase late tonight as deeper moisture moves into the mountains and temperatures drop. The greatest QG lift still looks to be tomorrow afternoon and evening as the trough crosses over the forecast area and a cold front slides across the area. During this time, snowfall rates up to an inch an hour will be possible across the northern mountains that could bring some slick travel conditions, mainly across the high mountain passes where surface temperatures will be coldest. Looking like storm totals between 3 to 9 inches will be possible, mainly for elevations above 9,500 feet, with the northern mountains favored to see the higher amounts. Though elevations as low as 7,500 feet may end up with a few flakes when all is said and done.

Across the lower elevations, scattered to numerous rain showers are expected, with even a few thunderstorms possible. The best precipitation chances are expected for the northern plains where the latest NBM shows a 50% chance of greater than .2" of precipitation possible from roughly Fort Morgan northward, dropping to 20-30% for probabilities of QPF over .4" for the same area. Much lighter QPF is expected for areas from roughly Adams County southward, where only a few hundredths are forecast. With the drier conditions expected over Lincoln County, the southern half has been put under a Red Flag Warning for Tuesday where gusty southwesterly winds to 40 mph coinciding with relative humidity values as low as 12% is expected between 11 AM and 8 PM.

Showers are expected to diminish from west to east across the plains through Wednesday morning, giving way to warmer temps and dry conditions for Wednesday afternoon under brief upper-level ridging. Temperatures will warm back up for Wednesday afternoon, with 60s and 70s forecast across the plains and 40s and 50s for the mountain valleys.

By Thursday, southwesterly flow is expected to return and increase ahead of our next more potent weather system that will drop out of the Pacific Northwest through the day. Winds are expected to increase that will likely lead to elevated to critical fire weather conditions over much of the lower elevations Tuesday afternoon. Much cooler temperatures and another round of mountain snow is expected with this system, and ensembles are currently indicating the potential for even some light snowfall accumulations possible for our lower elevations on Friday. Details still need to be ironed out for specific track and strength of this system, but the latest NBM shows between a 40% to 80% chance for at least .1" of snowfall for our lower elevations on Friday evening (higher chances along the Wyoming border, lower chances southward), as a cold front cools temperatures down to below freezing.

Beyond Friday, Saturday looks to remain cooler across the forecast area behind Friday`s cold front, with afternoon highs remaining below normal for a change. Beyond this, looks like upper-level ridging will begin to build over the western CONUS and we will return to warmer and drier conditions across the forecast area.

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.AVIATION /00Z TAFS through 00Z Wednesday/... Issued at 621 PM MDT Mon Apr 13 2026

Recent observations show that the circulation that was centered southeast of KDEN this afternoon has started to decay and shift east. Winds this evening are expected to stay NW-N before a northeasterly surge arrives at KDEN and KBJC around 04Z-05Z. Wind direction late tonight into tomorrow morning remains a bit uncertain, likely starting out with a NE-E direction before shifting around to northwest by early afternoon.

An increase in moisture at the mid levels will bring a chance for a few showers to roll off the foothills and into the plains Tuesday afternoon. Periods of 30-35KT wind gusts will be possible with any downbursts that develop. Winds will then gradually weaken and transition to more of a southwesterly drainage pattern late Tuesday evening. Low ceilings are not a concern through the forecast period.



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.FIRE WEATHER... Issued at 101 PM MDT Mon Apr 13 2026

Above normal temperatures and dry conditions are in place across the forecast area this afternoon, with breezy surface winds bringing elevated to critical fire weather conditions across much of the forecast area. Today`s Red Flag Warning will remain in place through 8 PM this evening for areas along our northern and southern boundaries where relative humidity values ranging from the single digits to low teens are expected to coincide with southwest gusts around 30 mph through the early evening. While areas within the RFW are expected to have the most critical fire weather conditions, there will be patchy critical fire weather conditions at times outside of the warned areas.

A weather system is expected to move across Colorado on Tuesday that will bring snow to the mountains and scattered to numerous showers to the lower elevations, with a few thunderstorms possible. A cold front is expected to slide across the forecast area, though with its timing expected not to reach the southern extent of the forecast area until the evening, critical fire weather conditions are expected to develop over southern Lincoln County by late morning with wind gusts between 35 to 40 mph and RH as low as 12% expected. Therefore, a Red Flag Warning has been issued from 11 AM to 8 PM for this area.

While a brief reprieve from critical fire weather conditions is expected on Wednesday (dependent on how much precip we see Tuesday), things are expected to be warm, dry, and breezy again on Thursday that will likely lead to widespread elevated to critical fire weather conditions developing across much of the lower elevations.

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.BOU WATCHES/WARNINGS/ADVISORIES... Red Flag Warning until 8 PM MDT this evening for COZ214-216-238- 241-242-246-247.

Red Flag Warning from 11 AM to 8 PM MDT Tuesday for COZ247.

&&

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DISCUSSION...9 AVIATION...AA FIRE WEATHER...9