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783 FXUS65 KBOU 281930 AFDBOU Area Forecast Discussion National Weather Service Denver/Boulder CO 130 PM MDT Fri Aug 28 2026 .KEY MESSAGES... - Isolated/scattered high based showers/storms this afternoon/evening with gusty winds. - Temperatures return to the 90s today and Saturday across the plains. - Thunderstorm coverage increases for late Saturday through Monday. && .DISCUSSION /Through Friday/... Issued at 1213 PM MDT Fri Aug 28 2026 Things have warmed up fairly quickly this morning, with multiple observations at or approaching 90F already across the metro area (as of 11:30 AM), as an upper-level ridge remains centered over Arizona. Should see at least a few more degrees of surface heating before high-based showers/storms develop bringing some heat relief from west to east across the forecast area. The main threat from convection today remains with gusty outflows/microbursts. While instability is lacking to support very much in terms of strong thunderstorms across the majority of the forecast area, better low- level moisture and instability is expected for our far northeast counties, where we could see an isolated severe storm this evening. Despite the lacking instability, DCAPE values are expected to range from 1300-1500 J/kg across the plains, which will be enough for an isolated severe wind gust or two from anything that does develop. Hi-res guidance keeps this potential mainly for northeastern Larimer County and for areas east of I-25. Showers/storms are expected to diminish through the evening, with above normal temperatures expected across the forecast area. The next few days will remain fairly active as multiple disturbances move through the flow aloft and the ridge continues its eastward trek. For Saturday, the center of the ridge will be near the Texas Panhandle, with flow aloft becoming slightly more west-southwesterly over Colorado. A more pronounced mid-level disturbance and increased PWATs will aid in slightly higher shower/storm coverage for the afternoon/evening. Scattered high- based showers/storms are expected to develop by early afternoon, with an isolated severe wind threat once again. Slightly cooler temperatures are expected across the forecast area as 700 mb temperatures see a few degrees of cooling. Flow aloft will become increasingly southwesterly as the ridge moves eastward through the weekend. Ensembles show PWATs remain elevated and we should be able to tap into some monsoonal moisture at least at the upper levels, while lower level moisture will remain more limited. We should see at least scattered showers/storms each afternoon, with Monday bringing the best chances for more meaningful rainfall this week, with increasingly drier conditions expected beyond that. Temperatures are expected to see a few days of sub 90 degrees for a change on Monday and Tuesday across the plains. && .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...9 AVIATION...RPK