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379 FXUS65 KBOU 260221 AFDBOU Area Forecast Discussion National Weather Service Denver/Boulder CO 821 PM MDT Tue Mar 25 2025 .KEY MESSAGES... - Mostly dry weather Wednesday through Friday, with above normal temperatures. - Cooler with a chance of precipitation Friday night into early next week. && .UPDATE... Issued at 748 PM MDT Tue Mar 25 2025 It`s a fairly calm night across the forecast area this evening. One may even suggest it feels like spring! Waves of weak boundaries associated with passing virga showers over Larimer and Weld Counties have been sliding across portions of the northern plains, washing out as they move over the airfields at KDEN. Once these dissipate in the next hour or two, diurnal winds are expected to resume for the overnight hours. Aside from adding in current observations, no significant changes were made to the current forecast. && .SHORT TERM /Through Wednesday/... Issued at 245 PM MDT Tue Mar 25 2025 North and northwesterly winds are blowing across most of the plains early this afternoon. Current temperatures are mostly in the mid to upper 60s over the plains at this time. Convective cloudiness continues to develop over the mountains north of I-70, the foothills and most of the plains. Models keep upper ridging over the CWA tonight and on Wednesday with benign synoptic scale energy expected. Will decrease what little cloudiness I have early this evening after sunset. Model cross sections show it to be pretty dry overnight and on Wednesday. Normal diurnal wind patterns are expected tonight and on Wednesday with fairly weak speeds. Temperatures on Wednesday look to be 2 to 4 C warmer than today`s highs. && .LONG TERM /Wednesday night through Tuesday/... Issued at 245 PM MDT Tue Mar 25 2025 The main weather feature will be above normal warmth Thursday and Friday. Upper ridging and weak flow aloft is expected Wednesday night into Friday morning. Southwesterly flow aloft is progged on Friday. A weakening upper trough will get into the CWA late Friday night. The QG omega fields indicate benign synoptic scale energy into Friday morning, then weak upward vertical velocity is progged the rest of the Friday and Friday night. The low level pressure and wind fields show fairly weak drainage winds Wednesday night, then Thursday`s winds will be dominated by southwest and westerly flow but not significantly strong. There will be a mix of normal drainage winds and downsloping Thursday night. More downsloping on Friday. For moisture, there are limited amounts in the mid and upper levels Wednesday night into Friday. Moisture increases Friday afternoon and night with the weakening trough. There looks to be enough moisture along with the weak lift for some 30-60% pops for much of the CWA Friday evening, decreasing overnight. The plains will have mostly rain showers as temperatures stay pretty warm overnight. Snow fall amounts do not look significant in the mountains. For temperatures, highs on Thursday and Friday are close to 20 degrees F above seasonal normals for the plains with mid 70s to lower 80s both days. Those type readings could set new record highs in some places, especially on Thursday where Denver`s record is 78 F. For the later days, Saturday through Tuesday, there is fairly strong west-southwesterly flow aloft on Saturday with an upper trough progged to move across Colorado Saturday night into Sunday morning. Strong upward motion is indicated Saturday night into Sunday morning on the QG Omega fields. Now the GFS looks to be the strongest with this feature. Consistency has not been good between the models or between the model runs. Models show a decent colder airmass to move into the plains and foothills on Saturday. Now, the QPF fields have pretty decent measurable precipitation for much of the CWA Saturday afternoon into Sunday midday. Snowfall in the mountains could be significant enough to warrant highlights eventually. The plains should turn to all snow by sometime Saturday evening, however the bunt of the precipitation will likely fall as rain. It is still a ways away and the consistency of the models has not been great. Monday and Tuesday could be somewhat unsettle with the models showing weak, broad upper troughing and strong flow aloft. For temperatures, readings look to be around seasonal normals Saturday, Monday and Tuesday, with Sunday the coolest day. && .AVIATION /00Z TAFS through 00Z Thursday/... Issued at 547 PM MDT Tue Mar 25 2025 VFR conditions expected through the TAF period. A weak outflow from NW to SE moving virga showers over central Weld County is currently battling the diurnal SE winds to bring E to NE winds to KDEN. These are expected to return to the SE once the showers move away, in the next few hours. Once this happens, winds will return to the typical diurnal pattern, shifting to the S near midnight (6-7Z). For tomorrow, winds are expected to make a turn "around the clock" through the morning, making their way to the east at all TAF sites between 21-23Z. && .BOU WATCHES/WARNINGS/ADVISORIES... None. && $$ UPDATE...Bonner SHORT TERM...rjk LONG TERM....rjk AVIATION...Bonner