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329 FXUS65 KBOU 231853 AFDBOU Area Forecast Discussion National Weather Service Denver/Boulder CO 1253 PM MDT Sun Aug 23 2026 .KEY MESSAGES... - Scattered afternoon and evening showers and storms through Thursday. A risk of a couple severe storms each day especially Tuesday and Wednesday. - Slightly cooler with near normal temperatures for Tuesday and Wednesday. - Gradual drying and hotter temperatures by the end of the week and through next weekend. && .DISCUSSION /Through Sunday/... Issued at 1245 PM MDT Sun Aug 23 2026 The flow aloft will be mainly WNW this aftn thru tonight with PW values 100 to 150 percent above normal. Don`t really see anything aloft to enhance tstm development, so will see another round of sct showers and storms across the CWA. Overall, expect mostly outflow dominant storms with gusty winds and possibly some marginal large hail over the plains. DCAPE values are mainly at or below 1000 j/kg but a few storms may still produce brief wind gusts from 55 to 65 mph. On Mon, the flow aloft will remain WNW with some decrease in moisture as PW values drop to 100 to 125 percent above normal. As a result, may see less activity Mon aftn and evening. DCAPE values are fcst to rise to 1000 to 1500 j/kg, so there will be some potential for gusty outflow winds from the activity. Highs will be in the upper 80`s to mid 90`s. For Tue, the flow aloft will be slightly stronger from the WNW as a weak cool front moves into nern CO. As a result, will see temperatures drop back to more seasonal levels with an increase in low level moisture across nern CO. Will see a better chc of showers and tstms across the higher terrain by aftn. Across the plains, initial tstm development may focus over the Cheyenne Ridge and Palmer Divide by mid to late aftn and then track across the plains by Tue evening. MLCAPE will range from 1000-1500 j/kg with favorable shear. Thus would expect a few svr storms across the plains. On Wed, the flow aloft will become more NWLY. MLCAPE will range from 1000-1500 j/kg, across nern CO, with the higher values over the I-25 Corridor. With favorable shear, should see a few svr storms by mid to aftn along portions of the I-25 Corridor which will move across the plains during the early evening hours. Over the higher terrain will see sct showers and storms. Highs on Wed, will stay in the 80`s across the plains. Looking ahead to Thu and Fri, the upper level ridge will extend from the srn Rockies into the swrn US. As a result, this will leave the area in WNW flow on Thu becoming more westerly by Fri. Current data shows some decrease in moisture both days, however, still expect sct showers and storms over the higher terrain with widely sct activity across the plains. Highs will be near seasonal levels on Thu and then back to above normal by Fri. By next weekend, the flow aloft will become more WSW. Will still see some influx of monsoon moisture with widely sct showers and tstms possible both days. Highs will remain above normal. && .AVIATION /18Z TAFS through 18Z Monday/... Issued at 1206 PM MDT Sun Aug 23 2026 Winds have turned northward in the last couple of hours, and should remain north/northeast until storms start to move through the area. Model guidance continues to show convection initiating around 21Z, so we`ve kept that as the start time for the TEMPO; however, given that this morning`s inversion has disappeared in the recent ACARS soundings, and cumulus has started building over the foothills, it wouldn`t be out of the question to see some showers and wind gusts as early as 20Z at KDEN. Gusty outflows with shifting winds (30- 40kts) remain more of a threat than precipitation over the TAF sites. Recent CAMs runs also keep showers lingering as long as 03- 04Z, so we`ve opted to extend the PROB30 another hour to account for that. Clouds should clear up and winds should shift towards drainage after any lingering showers/outflows move out of the area, sometime between 03-05Z. Winds will then turn back to the north in the morning, around 15Z. Another round of showers/storms/outflows is expected at about the same time tomorrow, starting around 21-22Z. && .BOU WATCHES/WARNINGS/ADVISORIES... None. && $$ DISCUSSION...RPK AVIATION...AGS