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491 FXUS65 KBOU 041131 AFDBOU Area Forecast Discussion National Weather Service Denver/Boulder CO 531 AM MDT Fri Sep 4 2026 .KEY MESSAGES... - Warm and mainly dry conditions through Saturday, with isolated afternoon showers/storms favoring the high country. - Increasing moisture Sunday/Monday with a rise in shower/storm coverage, including for the lower elevations. - Warm temperatures favored to continue next week, with at least isolated to scattered showers and storms most afternoons. && .DISCUSSION /Through Thursday/... Issued at 223 AM MDT Fri Sep 4 2026 There haven`t been any notable changes to the forecast over the last couple of days. I`m not sure if this pattern would technically qualify as an omega block - with two closed lows off the Pacific Northwest and New England, with a large ridge in between - but either way most of Colorado will be "blocked" out of any meaningful pattern change over the next week or so. Dry southwesterly flow aloft remains in place this morning, per water vapor satellite imagery. The ridge centered across the south central CONUS is expected to gradually strengthen today and shift a bit westward. We`ll start to see a bit of moisture creep into the southern half of our CWA by this evening, which could lead to isolated or widely scattered showers and a few thunderstorms late this afternoon into the evening. Otherwise, temperatures should be a couple degrees warmer than yesterday. The flow aloft should turn to more of a S/SSW direction by this weekend, allowing for better moisture advection into the region. This should result in widely scattered but relatively weak convection across most of the high country. Continued moisture advection is likely for Sunday and Monday. With an increase in boundary layer moisture, convection should be more widespread but still limited in coverage given essentially no large scale/synoptic support. As mentioned in the past few forecast cycles, models begin to diverge by early or mid-week next week. However, the overall pattern would still favor a ridge off to our east with some sort of cutoff low or open trough near the west coast. Moisture should remain over our area - leading to continued chances of afternoon showers or thunderstorms - but significant/widespread rainfall still appears unlikely with no notable shortwaves or fronts moving through. && .AVIATION /12Z TAFS through 12Z Saturday/... Issued at 521 AM MDT Fri Sep 4 2026 VFR through the TAF period. Weak cyclone still evident based on surface observations across the Denver metro. Light and variable winds are likely to persist through most of the morning. Eventually we should see a better defined cyclone/shear zone develop after 18z this afternoon. Most guidance keeps winds out of the east at DEN/BJC with a little less confidence for APA. There`s still a low end chance of seeing a shower or two this afternoon or evening, though recent guidance is has trended towards less convection. The previous PROB30s weren`t adjusted at this point. Winds will eventually turn southeast during the evening before settling on drainage for most of Friday night. && .BOU WATCHES/WARNINGS/ADVISORIES... None. && $$ DISCUSSION...Hiris AVIATION...Hiris