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899 FXUS65 KBOU 261134 AFDBOU Area Forecast Discussion National Weather Service Denver/Boulder CO 534 AM MDT Fri Jun 26 2026 .KEY MESSAGES... - Scattered showers and thunderstorms return this afternoon, and a few may become strong to severe in the plains. - Widespread and prolonged critical fire weather conditions will be present in the high country this weekend as warm, dry and windy conditions develop, continuing at times into early next week. - All areas will trend warmer and drier this weekend, with little change into next week. && .DISCUSSION /Through Thursday/... Issued at 1234 AM MDT Fri Jun 26 2026 Our stretch of active weather will come to a close soon, but we have one more day of afternoon thunderstorms to contend with before truly warmer and drier conditions return. Moisture levels do tick down slightly today, but PW values will still range between ~0.8" over the urban corridor to around 1.10" in the eastern plains - plenty sufficient for additional rain with any afternoon storms. Guidance is rather variable as far as CAPE is concerned for the urban corridor, though maintains moderate to healthy instability over the plains. With little if any stratus currently present over the lower elevations, and one additional shortwave approaching from our west, suspect convection today will be more widespread compared to what earlier model guidance had been suggesting. Despite a decline in lapse rates and bulk shear values, both parameters should still be sufficient to support isolated strong to severe storms later in the afternoon and evening, particularly for the plains. On a positive note, the combination of recent rainfall and more subdued fire activity to our west yesterday will result in vastly improved air quality today, with much less smoke aloft. We remain on track for the arrival of much warmer and drier weather for this weekend as a ridging pattern takes hold over the central plains. Strengthening southwest flow aloft ahead of a trough to our west will generate hefty winds, most notable for the high country, and drive a prolonged period of high fire danger that will continue into early next week. Fortunately, more abundant green-up and recent precipitation will keep those concerns limited east of the Front Range mountains. All areas look to remain dry through at least Monday, and temperatures across the lower elevations will quickly rebound into the mid to upper 90`s this weekend. If we can keep cloud (and smoke) coverage to a minimum, we`ll likely see the hottest temperatures of the year so far Saturday and/or Sunday. The remainder of the week looks to be characterized by continued above-average temperatures and generally low precipitation chances, as Colorado remains anchored between a troughing pattern to our west and a ridge over the plains. That said, a few shortwaves embedded in the southwest flow regime may lead to isolated afternoon showers or weak thunderstorms some afternoons. Elevated to at times critical fire weather conditions will persist in the high country given stubborn breezy winds much of the week. && .AVIATION /12Z TAFS through 12Z Saturday/... Issued at 526 AM MDT Fri Jun 26 2026 VFR conditions will prevail for all terminals through the TAF period. Current southerly drainage winds should see a slight SW- ward shift through the next 2 hrs before giving way to a brief window of weaker and more VRB winds in the morning. Near midday, expect development of E/SE flow, which will strengthen through the afternoon, particularly for KDEN and KAPA. Scattered SHRA and TSRA are expected to develop near 20Z and migrate east, with the greatest chances of impacts being for KDEN. It`s a tough call between the PROB30 group and a TEMPO for afternoon convection, but confidence in TSRA impacts is currently closer to ~40% (and 20-30% for KBJC and KAPA). Outflows will be of concern during the mid to late afternoon period with gusts as high as 30-35 kts possible. Gusts to ~25 kts can be expected irrespective of TSRA activity in the vicinity of the terminals. Activity should dwindle past 00Z, and end by 01Z at the latest, with winds continue to veer SE and eventually S overnight. Drainage winds will remain hefty through early Sat AM and may produce gusts of 20-25 kts at times for KDEN and KAPA. && .FIRE WEATHER... Issued at 1234 AM MDT Fri Jun 26 2026 Fire weather concerns will be limited today given increased moisture and continued scattered showers and thunderstorms. Much warmer, drier and above all windier weather will arrive near midday Sunday, with the strongest winds impacting the high country with sustained speeds approaching 25 to 30 mph and gusts as high as 50 mph expected. With humidity descending into the low teens during the afternoon, critical fire weather conditions will become widespread. This warm, dry and windy pattern is set to continue into Sunday and Monday, with only slight moderation in wind speeds and/or humidity levels anticipated. As such, expect periods of critical fire weather conditions to continue each day in the high country, including both the mountains and high valleys. Greener fuels and recent precipitation will keep fire danger much lower across the lower elevations and much of the foothills. && .BOU WATCHES/WARNINGS/ADVISORIES... Red Flag Warning from 11 AM Saturday to midnight MDT Saturday night for COZ211>214-217-218. && $$ DISCUSSION...BRQ AVIATION...BRQ FIRE WEATHER...BRQ