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936 FXUS65 KBOU 100548 AFDBOU Area Forecast Discussion National Weather Service Denver/Boulder CO 1148 PM MDT Mon Mar 9 2026 .KEY MESSAGES... - Much above normal temperatures again Tuesday, with elevated to critical fire weather conditions. Highest along the I-25 Corridor from northern portions of the Denver Metro area to the Wyoming border. - Chance of snow showers for the mountains and northern plains Tuesday night. In addition gusty north winds up to 50 mph over the plains Tuesday night behind a cold front. - Cooler on Wednesday with elevated to critical fire danger at lower elevations near the Wyoming border. - Strong winds and critical fire weather concerns possible Thursday through Saturday. && .DISCUSSION /Through Monday/... Issued at 1138 PM MDT Mon Mar 9 2026 For Tue, a shallow surge of cooler air will move across the nern plains in the morning and may reach the nrn portions of the I-25 Corridor before mixing out some by aftn. To the west of this boundary highs will reach the lower to mid 70`s while over the far nern plains may stay in the upper 50`s to lower 60`s. By Tue night, an upper level trough will move across Wyomning with nrn CO being on the srn edge of this feature. In addition, a stronger cold front will move across the plains in the evening with gusty north winds behind it. Cross-sections show some moisture will affect the nrn mtns and portions of the nern plains closer to the WY- NE border. Furthermore, the nose of stronger upper level jet will allow for the far nern plains to be in the left front quadrant of the jet. Thus will see a good chc of snow showers in the nrn mtns overnight with a chc of rain/snow showers near the WY-NE border. Meanwhile, with 40-50 kt flow in the boundary layer across the nern plains, there will be a brief threat for gusty winds from 50 to 60 mph associated with the showers. At this time, not sure about overall coverage and how long they will last so have decided not to issue any high wind highlights. On Wed, drier air in NW flow aloft will move across the area. Latest data suggest some moisture may linger thru the mid morning hours in the mtns which may lead to a slight chc of snow showers. Otherwise it will be dry with cooler temperatures as highs drop back into the 50`s across the plains. For Wed night thru Thu night the flow aloft will become more WNW with only some higher level moisture embedded in the flow. Will see very windy conditions develop over the higher terrain late Wed night which will continue thru Thu night. At this time, hard to say how strong of a mtn wave there will be on Thu and whether the stronger winds will mix down to lower elevations below 6000 ft. For now, it appears areas in and near the nrn Foothills and adjacent plains, closer to the WY-NE border, will have some potential for stronger winds. Highs on Thu will rebound back into the upper 60`s to lower 70`s across the plains as downslope warming occurs. On Fri, dry WNW flow aloft will remain over the area. A weak front may move into far nern CO in the morning. However, by aftn a sfc lee trough will intensify from ern WY into ern CO. Thus it will be another windy day over the high terrain and portions of the plains. With downslope low level flow in place, high across the plains will be in the 70`s. For the weekend, an upper level trough will move from the Pacific NW into the area Sat night into Sun. Ahead of this feature, there could be another round of stronger winds over the higher terrain and portions of the plains on Sat with another day of much above normal temps. Sat night there will be a strong cold front moving across the area with much cooler temperatures for Sun. Meanwhile, depending on how much moisture there will be behind the front, there could be a chc of snow across the plains Sat night into Sun as the upper level trough moves across. In the mtns, there should be a good chc of snow as well. && .AVIATION /06Z TAFS through 06Z Wednesday/ ... Issued at 1140 PM MDT Mon Mar 9 2026 VFR will persist through the TAF period. Winds have mostly turned southwesterly and should persist through about 15Z-16Z before starting to increase again. However, there is a shallow backdoor cold front to watch that`s moving into northeast Colorado. That could turn winds northeasterly or even variable (30-40% chance) for a brief bit 12Z-16Z. For now, we`ve kept the prevailing southwest direction in the TAF but still something to watch. We do think daytime heating/mixing will dominate after 16Z which means an increase in westerly winds through 18Z-21Z, continuing through at least 24Z. Peak gusts up to 35 knots are possible at BJC and up to 30 knots at DEN and APA, although averages should be about 5 kts less than that and mostly below critical N-S crosswind thresholds at KDEN. A cold front is still on track to move through all terminals around 02Z-04Z Wednesday. Gusty winds up to 35 knots are possible behind the front from the northeast. Wind should weaken toward 06Z and turn more easterly as an anticyclonic flow pattern develops across northeast Colorado. We`ve introduced a SCT deck at 5K ft due to upslope and some moisture behind the front, but overall it looks like a small 20% threat that ceilings would be low enough for IMC. && .FIRE WEATHER... Issued at 1138 PM MDT Mon Mar 9 2026 It will be another warm dry day Tuesday over northeast Colorado with relative humidities in the teens. Elevated to locally critical fire weather conditions are expected during the afternoon hours, espeically from along the I-25 Corridor from Denver north to the Wyoming border where wind gusts to 35 mph will be possible. A cold front brings a wind shift Tuesday evening and cooler temperatures for Wednesday. Locally elevated to critical fire weather conditions will be possible in the afternoon over far north and northeast Colorado where breezy conditions are expected. Very warm and dry conditions return to the area Thursday through Saturday. A surface low passing north Colorado will tighten the pressure gradient, bringing very windy conditions to portions of the area on Thursday. Strong winds are also a possibility for the foothills if a mountain wave forms. Windy conditions will continue to be possible Friday and Saturday under an increasing northwest flow aloft. Overall, there will be elevated to critical fire conditions Thursday through Saturday below 7000 feet. && .BOU WATCHES/WARNINGS/ADVISORIES... None. && $$ DISCUSSION...RPK AVIATION...20 FIRE WEATHER...RPK