National Weather Service Forecast Discussion |
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203 FXUS65 KBOU 081830 AFDBOU Area Forecast Discussion National Weather Service Denver/Boulder CO 1230 PM MDT Wed Jul 8 2026 .KEY MESSAGES... - Scattered to numerous thunderstorms, with a few strong to severe storms over the eastern plains. - Another round of scattered to numerous thunderstorms Thursday, with the severe threat possibly expanding west to the Front Range. - Prolonged period of hot temperatures arrive Saturday, lasting through at least Tuesday. Thunderstorm chances remain low during this period. && .DISCUSSION /Through Wednesday/... Issued at 1230 PM MDT Wed Jul 8 2026 Warm, dry, and gusty west winds prevail along and west of I-25. Mid level moisture and a weak wavewill help produce isolated/scattered high-based showers and thunderstorms this afternoon with gusty outflow winds up to 60 mph possible with this activity. Radar shows a boundary across Weld County where west/northwest winds meet the northeast winds. East of this boundary, the northeast winds are ushering in moisture with dew points in the upper 50s to lower 60s. The main severe weather threat today is east of the boundary. In addition to much better moisture, ML CAPE reaches 500-1500J/kg. Main threat will be gusty outflow winds up to 70 mph, but a few storms could produce severe hail as well. Storms will progress eastward across the plains, exiting the area this evening. A few overnight showers will also be possibleover the mountains where a weak wave will track. For Thursday, the pattern will generally be the same with a few slight differences. We`ll see stronger westerly flow aloft Thursday as a speed max passes over the area. Better moisture is expected to push westward, but there is some uncertainty just how far west it will be. Where better moisture resides, we`ll see MLCAPE of 1000-2000J/kg and plenty of shear for severe thunderstorms. The initial storms are expected to form over the higher terrain. Storms should increase in strength and coverage as they travel eastward, encountering better instability and moisture. High-Res models favor a couple line segments. or possibly one large line tracking across the eastern plains during the afternoon and early evenings hours, favoring a strong wind threat. Upper level ridge off to the southwest begins to strengthen Friday. Flow aloft weakens and turns to the northwest. Low level flow will continue to be easterly, helping to hold onto better moisture across the plains and possibly as far west as the urban corridor. Expect another round of afternoon and early evening thunderstorms to track across the urban corridor and eastern plains. For Saturday through Wednesday...the upper level high builds northward and will be centered over the Central and Southern Rockies Saturday. Temperatures will warm into the mid 90s across northeast Colorado. Easterly low level winds may help hold some moisture across eastern Colorado, however warm air aloft is expected to cap the atmosphere, and prevent storms from forming. The upper level high lifts northward and then remains semi- stationary over the north central part of the country through the middle of next week. Very warm temperatures are expected with highs reaching the mid to upper 90s. Easterly low level flow will prevail during this period and provide just enough cooling to prevent widespread low 100 degree heat from occurring. These east winds likelyhold in enough moisture to limit the fire weather threat as well. Very warm air aloft continues to cap the atmosphere. Can`t rule out a few thunderstorms over the higher terrain early to mid next week. Steering winds will be from the east, meaning storms will have a westerly component when they develop. This will keep the urban corridor dry this weekend and for most (perhaps all) of next week. && .AVIATION /12Z TAFS through 12Z Thursday/... Issued at 1230 PM MDT Wed Jul 8 2026 VFR conditions expected through the TAF period. North winds may briefly be gusty this afternoon with gusts up to 20 knots possible at DEN and APA and 30 knots at BJC. Scattered showers and storms are expected to develop after 19Z with strong outflow winds that could potentially reach 45 knots at DEN and APA. After these storms move out of the area, southeast winds are expected to develop late this afternoon and evening. There will generally be light winds tonight with drainage flow although a weak boundary may bring north winds at all terminals by 10-12Z. Thursday looks similar to today with afternoon showers and storms producing strong outflow winds up to 45 knots. The most likely timing for storms is between 20-23Z. && .BOU WATCHES/WARNINGS/ADVISORIES... None. && $$ DISCUSSION...12 AVIATION...Danielson