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500 FXUS65 KBOU 060552 AFDBOU Area Forecast Discussion National Weather Service Denver/Boulder CO 1152 PM MDT Mon Oct 5 2026 .KEY MESSAGES... - Unseasonably warm through at least Saturday. - Only isolated to scattered showers (15-30% coverage) for the mountains and higher terrain. Any precipitation would be light. - Pattern change late this weekend and early next week, but considerable uncertainty as to when and how much temperatures will cool and what chance of precipitation we`ll see. && .DISCUSSION /Through Monday/... Issued at 1054 PM MDT Mon Oct 5 2026 An upper level ridge will dominate our weather through the end of the week with much above normal temperatures. While mostly dry weather will prevail, a weak disturbance to our west combined with slight moistening under the ridge will lead to a few late day showers. While most of those will be confined to the mountains, we can`t totally rule out some virga, gusty winds, and even a couple light late day showers spreading off the mountains onto the Palmer Divide area and adjacent plains. Tuesday will start off with shallow inversions and thus a fairly quick warmup is expected again, similar to Monday. Upper level clouds will be increasing slightly, but overall do not expect enough opacity to limit daytime heating by more than a degree or two. Thus, forecast highs of 85-90 seem on target across the plains with the near 90 degree readings in the South Platte River valley. That puts us near record highs again (For example, Denver`s record is 87F set in 1975 and 2020 and we should be within a degree of that, Fort Collins record of 85F set in 1905 will likely be broken). While there is just slight cooling in the column for both Wednesday and Thursday, temperatures will remain well above normal. We still expect most of the plains and I-25 Corridor to reach the lower to mid 80s under the ridge. Once again, can`t rule out isolated to scattered showers/lone storm mainly over the mountains. Friday and Saturday will still be warm and mostly dry as we turn to more of a southwest flow aloft in advance of the next storm system. That system will dig southward down/near the Pacific Coast Sunday and Monday, eventually allowing a cold front to slip southward across the High Plains. It`s just that in this pattern with a more southerly flow aloft it makes timing of these frontal surges difficult to get a handle on. That is clearly pointed out in the sudden spread of ensemble temperature forecasts for both Sunday and Monday. The same can be said for our precipitation chances with potential for interaction/incorporation of Hurricane Rachel remnants. Overall, the forecast will reflect a cooling trend with increasing chances of showers Sunday through early next week. && .AVIATION /06Z TAFS through 06Z Wednesday/... Issued at 1150 PM MDT Mon Oct 5 2026 VFR conditions through the TAF period. Current observations show a weak push of NNW winds over the Denver metro but we expect a quick return to SSW/SW drainage winds within the next hour or so. Winds will likely become light and variable by 15Z Tuesday morning before gradually turning NE-E. Shower activity Tuesday afternoon looks to be isolated in nature and mainly over the mountains. However, a rogue outflow boundary/wind shift cannot be ruled out if a high-based shower makes it off the foothills (15% chance). && .BOU WATCHES/WARNINGS/ADVISORIES... None. && $$ DISCUSSION...20 AVIATION...AA