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051 FXUS65 KBOU 190559 AFDBOU Area Forecast Discussion National Weather Service Denver/Boulder CO 1159 PM MDT Sat Oct 18 2025 .KEY MESSAGES... - Widespread freeze expected for the rural plains and northern I-25 corridor Saturday night. - Warmer Sunday with a slight reprieve in winds, but low humidity will keep fire weather conditions near critical. - Another potent front arrives early Monday, bringing light mountain snow north of I-70, widespread strong winds, and critical fire weather conditions. - Lighter winds will more seasonal temperatures Tuesday onward. Potential for some showers Wednesday night and Thursday, with best chances in the mountains. && .DISCUSSION /Through Saturday/... Issued at 148 PM MDT Sat Oct 18 2025 To the relief of many, winds have begun to ramp down for all areas after this morning`s potent cold front. Still, we`ll hold onto breezy conditions over the plains and mountains the rest of the day, before the gusty winds subside more noticeably for the lower elevations overnight. We saw a hefty temperature drop of 10 to as much as 20 degrees, so it`s no surprise we`re still on track for a relatively widespread freeze tonight across the plains. If winds are able to calm sufficiently, some patchy freezing conditions will likely also extend into traditionally colder outlying areas of the Denver metro, mainly to the north. The thermometer will bounce back Sunday as high pressure drifts overhead, leading to a mild and dry day across the board. While cross-barrier flow will remain near 45-50 knots and thus sustain breezy conditions over the higher mountain terrain, we`ll see a notable reprieve for the lower elevations in the absence of any mountain wave amplification mechanism. Opted to cancel Sunday`s Fire Weather Watch given these marginal wind conditions, although still suspect we will see short spurts of localized fingers with 25-30 mph gusts over the urban corridor which will promote near- critical conditions. In true Fall fashion, the wind won`t take long to make a reappearance. A jet max will arrive on Monday as an amplifying trough clips the state, driving another potent cold front south early morning. With the jet in place and healthy frontogenesis, there`s a greater potential for some mountain snow accumulation (mainly north of I-70) compared to this last system, though amounts should still be on the minor side (~1-3"). Precipitation elsewhere looks to be very limited, however the NBM`s 0% PoPs for Monday morning don`t quite capture the potential that inherently accompanies these frontogenic setups, so did introduce some slight (15%) PoPs into the forecast for the plains and urban corridor. The front will pack a punch, with gusts expected to hit 50 mph over the plains and 40-45 mph for the urban corridor. Its passage also looks early enough to allow for ample drying by the afternoon and, with post-frontal winds remaining gusty, critical fire weather conditions can be expected for much of the lower elevations. A Fire Weather Watch has thus been issued, mainly for areas south of I-76 where fuels are the most susceptible. Highs will fall back below seasonal averages and into the 50`s and lower 60`s for the lowlands. Both temperatures and winds will moderate midweek (Tuesday into Wednesday) as this trough exits eastward, replaced by weaker zonal to slightly northwest flow aloft. By Wednesday night, a lifting closed upper-level low will approach from the southwest and drift over Colorado into Thursday. Ensembles have been fairly consistent in showing a favorable track for at least some light mountain snowfall. QG lift and potentially some brief northeasterly upslope flow may promote a few showers for the urban corridor and plains as well, favoring areas south and west of Denver, although temperatures will generally be too warm to support snow for the lower elevations. Drier conditions with seasonal temperatures look to prevail as the low pushes east Friday into Saturday. && .AVIATION /06Z TAFS through 06Z Monday/... Issued at 1154 PM MDT Sat Oct 18 2025 VFR through Sunday. South winds will become west and increase with speeds of 10 to 20 knots 18z-20z, with a period of variable directions at light speeds possible before then. KBJC may have gusts up to 30 knots (20% chance). && .BOU WATCHES/WARNINGS/ADVISORIES... Fire Weather Watch from Monday morning through Monday afternoon for COZ216-239>241-245>247-249. Freeze Warning until 8 AM MDT Sunday for COZ038-041>051. Frost Advisory until 8 AM MDT Sunday for COZ039-040. && $$ DISCUSSION...BRQ AVIATION...Gimmestad