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271 FXUS65 KBOU 141929 AFDBOU Area Forecast Discussion National Weather Service Denver/Boulder CO 129 PM MDT Thu May 14 2026 .KEY MESSAGES... - Summerlike warmth through Friday with only isolated high based showers and a renegade storm or two. - Elevated to locally critical fire weather conditions through Friday. - Shower and storm chances will gradually increase this weekend through early next week, but some uncertainty as to when and how much. - Accumulating snow likely (>70% chance) for mountains and possibly foothills (30-50% chance above 7,500 feet) as temperatures turn colder toward Monday. && .DISCUSSION /Through Thursday/... Issued at 129 PM MDT Thu May 14 2026 Main concern in the very short term is elevated to critical fire weather conditions. We`ve seen the gusty west winds up to 20-30 mph spread off the foothills, and with further mixing and more sunshine this afternoon they will also spread across the northern plains with gusts as high as 35 mph there. Humidity readings will subsequently drop into the 9-12% range. Those conditions will only slowly improve as winds relax through the course of the evening. The current Red Flag Warning for the northern tier of plains counties is on track and will remain in effect until those winds decrease. Also, despite the slow heating today, with more sunshine we should still reach convective temperatures where a bit more moisture holds on to our south. Thus, an isolated high based shower/storm is still possible over the Palmer Divide area and far eastern plains well into this evening. While temperatures remain mild overnight, it won`t be as warm as last night since we`ll have less clouds and little if any downslope component. Friday will feature another mainly dry and very warm day. Winds will be lighter in all but the mountains and high valleys (where fuels were noted as being not receptive to rapid wildfire spread), so no fire weather highlights are needed. A return flow of low/mid level moisture will support at least a slight chance of thunderstorms from the Palmer Divide into the eastern plains of Colorado by Friday evening and overnight. Saturday`s main concern will shift toward thunderstorm chances and even the threat of a couple severe storms. Models are pointing to building low level moisture over the eastern plains, which means increasing MLCAPE of 500-1000 J/kg. Right now, we think the main threat of the strong/severe storms would be east of a Sterling to Akron to Limon line, but will watch closely as models can sometimes overestimate the amount of lee troughing and eastward push of the dryline, especially under the influence of weak upward QG forcing. Temperatures should trend down slightly with earlier development of clouds and convection. For Sunday, more uncertainty enters the forecast. The overall trend was still for a deeper low pressure system dropping into the Great Basin. At the same time, a cold front is forecast to push across northeast Colorado, resulting in at least shallow upslope flow. Depending on the amount of heating/instability (heavily reliant on strength/depth of cold front), we could see another threat of severe storms. We would think the front would mostly sag just to our south, keeping the main threat south and east of our forecast area or over the Palmer Divide at the very most. However, the trends of a deeper trough and stronger southerly flow component aloft are also supporting a slower advancement or stalling of the front over northeast Colorado. Therefore, Sunday could bring another day of strong or severe storms. We do think showers and storms will still become more widespread Sunday night into Monday as upper level QG support as the trough starts to eject east/northeast across Wyoming and northern Colorado. Northern Colorado would be most favored for meaningful precipitation, while points farther south could stay mostly dry depending on the trajectory of the ejecting upper trough. There are also differences with timing, as some models bring the trough cleanly northeast, while others hold energy back into the mean trough over the Great Basin. Thus, it could still stay showery and cooler through mid week before drier and warmer conditions develop for the latter half of next week. Overall, ensembles point to modest precipitation amounts, with 25th-75th percentiles in the 0.50 - 1.0 inch range for Denver metro, greater amounts to the north and lesser amounts to the south. Still a baseline of just 0.10-0.20" on the 10th percentile, which would be more likely if the trough ejects farther north. && .AVIATION /18Z TAFS through 18Z Friday/... Issued at 1122 AM MDT Thu May 14 2026 VFR conditions will prevail for all terminals through the TAF period. Current W winds are projected to turn NW between 20-22Z, with occasional gusts 18-23 kts possible through early evening. Close to sunset, expect a more northerly component to take hold briefly, before weakening after ~02Z and gradually rotating clockwise to drainage flow overnight. The latter will be more shortlived than usual, and a flip to SE and then E winds is expected by mid-morning Fri. && .BOU WATCHES/WARNINGS/ADVISORIES... Red Flag Warning until 9 PM MDT this evening for COZ238-242-248- 250-251. && $$ DISCUSSION...20 AVIATION...BRQ