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586 FXUS65 KBOU 281730 AFDBOU Area Forecast Discussion National Weather Service Denver/Boulder CO 1130 AM MDT Fri Aug 28 2026 .KEY MESSAGES... - Isolated/scattered high based showers/storms Friday with gusty winds. - Temperatures return to the 90s Friday and Saturday across the plains. - Thunderstorm coverage increases for late Saturday through Monday. && .DISCUSSION /Through Thursday/... Issued at 137 AM MDT Fri Aug 28 2026 An upper level ridge remains centered near the Arizona/New Mexico border early this morning, leaving most of Colorado in weak wester/northwesterly flow aloft. This ridge is expected to slowly shift eastward over the next several days with few other synoptic scale features of note. The plume of better monsoon moisture will remain well off to the west and northwest today. Modest mid-level moisture combined with deep mixing will lead to widely scattered showers and thunderstorms this afternoon, though most of the convection should be weak given only meager instability. Most forecast soundings show inverted-V profiles across most of the I-25 corridor, and gusty outflow winds will be the main hazard this afternoon and evening. Meanwhile, it`ll be another hot day today as 700mb temperatures climb back to 16-18C. High temperatures should reach the low to mid 90s across most of the lower elevations. Saturday features more of the same, with the flow aloft backing to the west-southwest. Models generally try to increase moisture aloft a bit, with precipitable water values settling near an inch across most of the I-25 corridor, with more anomalous PW across northern/northwestern Colorado. Guidance generally tries to develop a more organized band of showers and thunderstorms close to the Wyoming border, associated with a weak mid-level shortwave and cold front. The ECMWF remains a bit more bullish with this potential compared to the rest of tonight`s guidance, though even the more aggressive solutions don`t have much in the way of rainfall outside of the northern mountains/North Park. Moisture increases a little bit more on Sunday, with another weak shortwave racing through the southwesterly flow aloft. Surface moisture will remain a limiting factor with dew points in the 40s leading to meager CAPE values across most of the forecast area. Another, perhaps better defined shortwave moves through on Monday and will likely provide our best chance of rainfall, though sfc moisture/instability will again be a bit of a question mark. By mid-week, most of the remaining moisture aloft sinks off to the south, meaning that near/above normal temperatures and generally dry conditions are forecast through the rest of the period. && .AVIATION /18Z TAFS through 18Z Saturday/... Issued at 1122 AM MDT Fri Aug 28 2026 Expect sct high based showers with an isold tstm possible between 20z and 00z. Brief gusts up to 40 mph will certainly be possible. After 00z, coverage of showers should diminish and end around 02z. Winds will gradually become more NW/N by 21z and then switch to more NNE by 00z. Winds this evening will switch to SE/S by 02z and then SSW by 05z. On Sat, winds will become more WSW by 16z. Any high based showers/tstms should hold off until after 18z. && .BOU WATCHES/WARNINGS/ADVISORIES... None. && $$ DISCUSSION...Hiris AVIATION...RPK