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333 FXUS65 KBOU 022102 AFDBOU Area Forecast Discussion National Weather Service Denver/Boulder CO 202 PM MST Mon Mar 2 2026 .KEY MESSAGES... - Warm and dry today, with near-critical fire weather conditions across the Palmer Divide. - Mountain snow and low-elevation rain likely (>70% chance) tonight into Tuesday evening, favoring areas north of I-70. - Potential for colder storm system with more widespread snow Thursday night through Friday, although uncertainty in amounts remains. && .DISCUSSION /Through Monday/... Issued at 135 PM MST Mon Mar 2 2026 It`s warm again across most of our forecast area. Temperatures in the plains are generally in the 60s, with a few spots in the metro near or just above 70F at the time of this discussion. Thankfully, this has come without much wind. ACARS soundings from early this afternoon show very little wind through the lowest 1-2km of the boundary layer. There are still some stronger winds near the top of the PBL (~550mb), and every once in a while we`re still seeing a few gusts of 30-35 mph over the lower foothills and adjacent plains. We`ll have a brief pause in our stretch of above normal temperatures on Tuesday, as a weak storm system arrives. That shortwave is currently near the NV/ID border per water vapor satellite, and should continue to progress eastward tonight into tomorrow. As the lee cyclone over southeastern Colorado deepens during the morning hours, there should at least be a weak frontal surge moving across the plains. The "cold" air isn`t particularly impressive, but should be reinforced as the 850-700mb low redevelops near the CO/KS/NE border and upslope flow deepens a bit. The main questions remaining are (1) how much stratus develops over the area... and similarly what will that do to high temperatures, and (2) how much moisture will we see across the lower elevations? For temperatures, most guidance has a pretty robust/deep post-frontal stratus deck, keeping temperatures in the mid to upper 40s. There is still a rather large spread across the 12z model suite to sort out... though we did lower temperatures a few degrees in the grids. For precipitation, again its a rather mixed signal. The 500mb vort max passes almost right over the area, but that shortwave is in the process of almost completely shearing apart by the time it`s over our CWA. Like previous forecasts, the current one still favors the northern Front Range and Cheyenne Ridge, with little to no precipitation south of I-70 and east of I-25. The overall precipitation and snow forecasts were not changed significantly from previous forecasts... with a few inches for the higher terrain and mostly rain below around 7-7.5 kft. Ridging will make another appearance for Wednesday and Thursday, with south-southwesterly flow increasing ahead of a more organized trough. Temperatures should warm back into the 60s by Wednesday, with low 70s possible Thursday. Depending on how much wind translates down to the surface, there could be elevated to critical fire weather conditions across portions of the plains Thursday afternoon. The forecast gets far more complicated late Thursday into Friday. Guidance generally is in good agreement that the shortwave trough will transition towards a closed low at 500mb, settling over eastern Utah by Friday morning. The favored solution from deterministic models today is to break that low into two very distinct pieces - a weaker shortwave the ejects into the Central Great Plains, while the other piece is shoved southwestward and eventually turns back into a closed low off the southern California coast. As a whole, the ECMWF and its respective ensemble and AI ensemble are wetter across the reason than the GFS/GEFS/AIGEFS, but neither solution offers much in the way of confidence. There are some scenarios where the ejecting shortwave would be enough for some meaningful precipitation (and maybe even snow) for the lower elevations, but given the highly complicated setup here, it`s difficult to provide many details. We`ll see how this evolves over the next couple of days. By the upcoming weekend, it looks fairly likely that we`ll end up split between the cutoff low to our south and the primary jetstream to the north... leading to another period of mild and dry weather. && .AVIATION /18Z TAFS through 18Z Tuesday/... Issued at 1102 AM MST Mon Mar 2 2026 Winds have turned to more W-NW to start off this TAF, although indications are muddled for any clear trends through 21Z-00Z since mixing has been limited by a high cloud deck. We have seen a stronger W-SW component push across KAPA, but with lack of organized heating the wind fields may just turn more N-NW (60-70% chance) and stay lighter through most of the afternoon, or even become VRB at times (30% chance). KBJC would have the best opportunity (50-60% chance) of gusty WNW winds to ~25 kts, while KDEN and KAPA any gusts should stay under 20 kts, even if we do mix better. The signals for any clear direction through this evening are even more uncertain, so we`ve opted for a few hours of VRB winds until the first surge of a front occurs (toward 06Z-08Z) when winds should turn more northerly. A stronger frontal surge is likely by 15Z-16Z Tuesday, with a higher certainty that we`ll see stratus and MVFR ceilings developing by then. The stratus deck will have support from increasing shower coverage and narrower T/Td spread to the north, combined with a weak upslope component developing. That stratus deck will be hard to erode with continued N-NE flow through the day and showers becoming more widespread - enough to go TEMPO -RA for the afternoon hours. We think the most likely range for ceilings will be in the 1200-2000 ft range for most of the day, although a slight chance (20-30%) that ceilings briefly drop to 1000 feet depending on extent of showers. && .BOU WATCHES/WARNINGS/ADVISORIES... None. && $$ DISCUSSION...Hiris AVIATION...20