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190 FXUS65 KBOU 050548 AFDBOU Area Forecast Discussion National Weather Service Denver/Boulder CO 1148 PM MDT Sun Oct 4 2026 .KEY MESSAGES... - Dry and unseasonably warm through at least Saturday, with record/near record warmth on Monday. - Isolated showers possible (15-30% chance) most afternoons for the higher elevations, highest Tue. Precipitation, if any, will be highly localized. && .DISCUSSION /Through Sunday/... Issued at 1019 PM MDT Sun Oct 4 2026 An upper level high over the Great Basin will weaken a bit on Mon. Once again there is some mid level moisture embedded in weak NW flow aloft. As a result, can`t rule out isold high based showers over the high terrain. Meanwhile, with rising 850-700 mb temps along with downslope low level flow, highs may tie or break records, as readings reach the mid 80`s to around 90 over the plains. On Tue, a weak disturbance will affect the area with some increase in mid level moisture. Thus may see a slightly better chc of high based showers/isold tstms over the higher terrain in the aftn. Some of this activity may affect portions of the I-25 Corridor by late aftn or early evening. Over the rest of nern CO, it will remain dry with highs remaining 10 to 15 degrees above normal. By Wed, the flow aloft will remain weak WNW. There will still be some lingering mid level moisture over the higher terrain. Overall, will keep in a slight chc of high based showers/isold tstms. Once again highs will be 10 to 15 degrees above normal. For Thu and Fri, the flow aloft will gradually become more zonal by Fri. Still expect mainly dry conditions both days. The GFS tries to backdoor a cool front into nern CO on Fri while the ECMWF has downslope low level flow as a sfc lee trough is over nern CO. Overall, still believe highs will remain 10 to 15 degrees above normal across the plains both days. By next weekend, the flow aloft will increase from the WSW as an upper level trough develops over the Pacific NW on Sat. Should see another day of warm and dry conditions over the area on Sat. Meanwhile, both the ECMWF and GFS keep the upper level trough to the NW of the area thru Sun. Both models show some subtropical moisture embedded in the flow aloft which may lead to a slight chc of showers over portions of the higher terrain by aftn. Across the plains, it looks dry with another day of above normal temperatures. For late Sun through Mon, there are varying solutions as to how fast or slow the upper level trough will be as it moves eastward. The GFS is faster while the ECMWF is slower by at least 24 hours. Naturally, depending on the timing and how much it amplifies will have a significant impact on weather for next Mon and Tue. && .AVIATION /06Z TAFS through 06Z Tuesday/... Issued at 1133 PM MDT Sun Oct 4 2026 VFR conditions to prevail through the TAF period. Winds are in the process of slackening and should settle into drainage in the next few hours at KDEN/KAPA (SW ~9 kts), remaining light and variable at KBJC. Drainage winds should become light and variable for a few hours in the late morning/early afternoon, before a few hours of easterly winds develop for the late afternoon. There is a low chance (10-15%) that any high-based showers that develop over the high country produce some gusty outflows that bring a wind increase (15-20 kt gusts) and brief direction shift to the TAF sites, with the best timing between 0Z-2Z, and KBJC with the better chances. South-southwesterly winds should settle in at KDEN/KAPA for the overnight hours, with KBJC remaining more westerly. && .BOU WATCHES/WARNINGS/ADVISORIES... None. && $$ DISCUSSION...RPK AVIATION...9