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131 FXUS65 KBOU 301138 AFDBOU Area Forecast Discussion National Weather Service Denver/Boulder CO 538 AM MDT Thu Apr 30 2026 .KEY MESSAGES... - Mountain snow expected Thursday morning through Friday morning, with travel impacts likely for high mountain passes. - Rain showers likely (>70% chance) for Urban Corridor and adjacent plains, with highest coverage of beneficial precipitation Thursday afternoon. - Warmer and drier conditions expected for the weekend. - Chance of showers returns early next week, with potential (50-60% chance) of more meaningful precipitation toward late Tuesday or Wednesday. && .DISCUSSION /Through Wednesday/... Issued at 1158 PM MDT Wed Apr 29 2026 The unsettled stretch of weather this week continues... Current radar imagery shows showers located near and south of Denver. Showers will continue in this vicinity overnight, especially for southern and eastern portions of the metro, with light snow possible for the mountains. There will be a lull in the showers for the early morning on Thursday due to some dry air intrusion affecting most of the area, except for the Palmer Divide and southern Front Range Mountains. A 500 mb low will track over Baja California and far northern Mexico on Thursday into Friday. The latest model trends are continuing to keep this low to the south of the US-Mexico border for the duration of the event, though we are expecting decent QG lift and frontogenesis over our area. Additionally, we are expecting some upslope flow with cross sections showing around 10 to 20 kt winds and moderately deep moisture- up to 600 to 700 mb- enhancing QPF for the Palmer Divide and southern Front Range Foothills. This will result in showers and snow showers returning around midday Thursday and lasting into the evening. The cloud cover and showers will keep it feeling more like an early spring day with temperatures struggling to make it out of the 40s across the Urban Corridor and only reaching the 50s in the eastern plains. The biggest uncertainty in the forecast still remains the QPF for Thursday. Models have still been trending drier with this system, especially for areas north and east of Denver. The southern Front Range mountains (south of the I-70 corridor) and western areas of the Palmer Divide are expected to see the highest QPF due to a longer duration of more favorable upslope flow in these areas. These areas could receive 0.50" to 0.75" QPF with isolated higher amounts possible. Due to the aforementioned dry air, we expect a sharp cutoff in QPF with locations north and east of a line from Fort Collins to Greeley likely to only receive up to 0.20". The Denver area should receive 0.20" to 0.40" with the higher amounts in the western and southern portions of the metro. In general, we expect 5 to 13 inches of snowfall in the mountains, with the highest amounts south of I-70. Thus, a Winter Weather Advisory will continue for those locations on Thursday and early Friday morning. The snow level is expected to be near 6500-7000 feet. The Palmer Divide and foothills will receive snow, but pavement temperatures will likely be too warm for the snow to significantly affect travel. The greatest impacts will be confined to the higher passes and higher elevations, especially on Thursday afternoon and evening. Additionally, have lowered PoPs for Friday due to more dry air moving in behind a front. Some light rain (snow for the mountains) will remain possible on Friday, though precip amounts will be very low. Friday will be a warmer day than Thursday will high temperatures still about 10 degrees below average with cloud cover still in place. For the weekend, warmer and drier weather is expected as an upper level ridge builds over the Rockies. Ensemble guidance continues to be in good agreement of temperatures rising above seasonal normals Saturday through Monday, with temperatures reaching up to the low 70s on Sunday and Monday. Precipitation chances return to most of the forecast area as guidance hones in on a stronger upper level shortwave trough (possibly strengthening into a closed low) trekking across southern Colorado Monday night into Tuesday. As of right now ensembles show about a 50-60% chance for 24-hr QPF amounts of 0.50" or more for the Front Range mountains and southern foothills, and 20-30% chance for Denver and adjacent plains. Unfortunately for the northern and northeastern plains, it looks like they will miss out on much of the precipitation. However, will continue to monitor, as changes in the track of the system will change precipitation chances for our area. && .AVIATION /12Z TAFS through 12Z Friday/... Issued at 538 AM MDT Thu Apr 30 2026 Tricky CIG/VIS forecast today. High res models all night had been forecasting CIGs between 020 and 030, but only APA with a steady light rain has dropped that far and remained around there much of the night. There is still a lot of evidence for CIGS to drop to 015-030 at DEN and BJC later this morning, as APA showed us it just takes a shower to move overhead. This morning, the best shower activity was across south metro Denver, from APA southward. We don`t expect too much shower development this morning at BJC and DEN, thus have removed TEMPO groups and just gone with VCSH. Winds across the terminals will be light throughout the period, and should eventually go north by 14Z, then northeast midday into the afternoon. Shower coverage this afternoon has decreased on all the high res models. Still think there is more than enough moisture around, and with a slight increase in northeast upslope in a moist neutrally unstable environment, we do think a few showers will directly impact the terminals this afternoon. At DEN and BJC planning to handle with TEMPO groups, but the window for showers is likely going to be longer than 4 hours. MVFR conditions, even under a stronger shower should hold at DEN and BJC. APA has the best chance to see moderate rain this afternoon, but probably still right at the bottom of MVFR conditions. Shower activity across the terminals should weaken after 03Z, though could hang on an hour or two longer at APA. The low-level moisture decreases quite a bit at that time, and visuals are looking likely after 06Z. Light drainage winds (S to SSW at DEN and APA, SW at BJC) are expected early Friday morning at under 10 kts. && .BOU WATCHES/WARNINGS/ADVISORIES... Winter Weather Advisory until 6 AM MDT Friday for COZ033-034-037. && $$ DISCUSSION...MAI/MV AVIATION...Schlatter