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324 FXUS65 KBOU 091737 AFDBOU Area Forecast Discussion National Weather Service Denver/Boulder CO 1137 AM MDT Wed Sep 9 2026 .KEY MESSAGES... - Mainly dry today through Friday with warmer temperatures for Thursday and Friday. - Return to more unsettled pattern and cooler weather favored for next weekend with a chance of thunderstorms each afternoon. && .DISCUSSION /Through Tuesday/... Issued at 228 AM MDT Wed Sep 9 2026 For today, drier in westerly flow aloft will be over the area as a cold front move across the plains early this mornng. As a result, expect dry conditions with cooler temps as highs finally drop back to more seasonal levels. By tonight, the flow aloft will become more WNW as low level southeast flow develops which will lead to some return of moisture across the east central plains. Meanwhile, a weak disturbance embedded in WNW flow will combine with warm air advection and bring some nocturnal tstms, to portions of the sern plains overnight. Current data still keeps most of this activity over sern CO, with srn Lincoln county, being on the nrn fringe. For now have kept in chc pops mainly across srn portions of Lincoln county overnight. On Thu, the flow aloft will remain WNW as southerly level flow is across the plains. MLCAPE will rise up to 1000 j/kg over portions of the plains by aftn. For now, chances for tstms stll look on the low side as I can`t find a focus for activity. However, can`t rule out an isold storm or two across Lincoln and Washington counties. Meanwhile, temps will begin to warm as readings reach the upper 80`s to lower 90`s over nern CO. Looking ahead to Fri, zonal flow aloft will be over the area as a sfc lee trough develops over the plains. This will lead to another warm day as highs rise into the upper 80`s to mid 90`s over the plains. Meanwhile, models have some mid level moisture embedded in the flow, which may lead to a slight chc of higher based showers/tstms over the higher terrain. Across the plains, MLCAPE is rather minimal so chances of precip look low. For Fri night into Sat, zonal flow aloft will continue. Meanwhile, a cold front will move across Fri night into Sat morning. This front will drop temps back to more seasonal levels across nern CO. MLCAPE is fcst to be in the 500-800 j/kg across the plains with lower values across the higher terrain. Thus will keep in a slight chc for showers/tstms across the area for the aftn/early evening hours. By Sun, an upper level trough will move into the nrn Rockies with increasing WSW flow aloft across the area. At the sfc, a lee trough will intensify east of the mtns with southerly low level flow across the plains. MLCAPE is fcst to increase to 1000-1500 j/kg over portions of the the plains east of a pseudo dryline. Thus may see a few stronger storms by late aftn thru the evening hours. Highs on Sun, will likely rise back to above normal levels. Looking ahead to Mon, rather dry WSW flow aloft will be over the areas a cool front moves across the plains Sun night into Mon morning. Latest data still doesn`t show much low level moisture behind the front, so it may end up being dry with temps dropping back to seasonal normals. && .AVIATION /18Z TAFS through 18Z Thursday/... Issued at 1134 AM MDT Wed Sep 9 2026 VFR conditions expected throughout the period. Winds are expected to stay under 15 kts. Typical diurnal winds are expected for today and tonight with only a few upper-level clouds. Tomorrow morning, winds will briefly be VRB before turning to ESE in the afternoon. No precipitation is expected today or tomorrow. && .BOU WATCHES/WARNINGS/ADVISORIES... None. && $$ DISCUSSION...RPK AVIATION...MV