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542 FXUS65 KBOU 090623 AFDBOU Area Forecast Discussion National Weather Service Denver/Boulder CO 1223 AM MDT Thu Apr 9 2026 .KEY MESSAGES... - Scattered showers Thursday afternoon/evening. Rainfall amounts will be light (less than 0.10"). - A brief cool down Friday with a 20-30% chance for light rain. - Warm and mostly dry for the weekend. Scattered showers possible Saturday with a few thunderstorms, mainly over the mountains and far northeast plains. Dry Sunday. - A spring storm possible Tuesday/Wednesday with heavier precipitation amounts possible. && .DISCUSSION /Through Wednesday/... Issued at 1103 PM MDT Wed Apr 8 2026 Westerly flow aloft will be across the area on Thu as a weak disturbance is possibly embedded in the flow. Cross-sections show moisture is mainly limited to the mid levels. Sfc based capes are under 300 j/kg. Thus appears most activity in the aftn will be rather high based with brief gusty winds occurring with any shower activity. Highs will be in the lower to mid 70`s across nern CO. For Thu night, a cool front will move across the plains with some increase in low level moisture behind it. With upslope flow in the evening hours combined with the weak disturbance moving across, there could be a better chc of showers in the evening across the plains. Meanwhile, will likely see low clouds and some fog overnight into Fri morning. On Fri, the low level flow will gradually become southeast thru the day with a Denver cyclone developing. There will be a convergence zone associated with this feature by aftn. Sfc based cape near the convergence zone will be around 500 j/kg if temps rise into the upper 60s. Thus a few storms may develop by late aftn along this zone. Elsewhere across the plains, it will be cool with less instability as temps remain in the 50`s. In the mtns, there will be a chc of showers and possibly a tstm. For Sat, the flow aloft will be from the southwest. A disturbance embedded in the flow may bring a good chance of showers to the mtns. Across the plains, gusty south winds will develop as a sfc lee trough forms. Sfc based capes will be around 500 j/kg with possibly up to 1000 j/kg over the far northeast plains by late aftn. Thus could see a few stronger tstms by late aftn into the early evening hours over the far nern plains. Highs on Sat will be warmer as readings rise back into the 70`s over nern CO. By Sun, drier air in SW flow aloft will spread across the area which will limit precip chances. Highs will remain in the 70`s across the plains. For Mon, a storm system will move into the Great Basin with stg SW flow aloft over the area, as sfc low pres resides over nern CO. As a result, may see another warm and dry day across the plains. In the mtns, moisture will increase by aftn with a chc of showers. Looking ahead to Tue, quite a bit of uncertainty remains as to the timing and track of the storm system over the Great Basin. The latest GFS has it moving quickly over the area on Tue with the main low tracking across Wyoming. This track would favor the mtns for precip while the plains would be mainly dry and windy. Meanwhile, the 12z ECMWF was slower and further south with the low as it moves into ern ern Colorado by Tue aftn. As a result this would bring a better chc of precip to portions of the plains. Overall, will see varying solutions for this system over the next 3 to 4 days. && .AVIATION /06Z TAFS through 06Z Friday/... Issued at 1214 AM MDT Thu Apr 9 2026 VFR through the TAF period. Light drainage winds are expected to continue through the overnight hours, before slowly veering through Thursday morning. A more uncertain wind pattern sets up once again Thursday afternoon. Initially, winds should favor a typical north/northeast turn by the early afternoon hours. As high-based, weak showers develop between 19-21z, winds may become a bit more erratic with most of the SHRA capable of producing some variable/gusty winds through most of the afternoon hours. DCAPE near/above 1000 J/kg would favor a couple of gusts up to 30kt, mainly between 20-00z. Can`t completely rule out a couple of lightning strikes given some very modest instability. Some SHRA may linger into the evenings hours before diminishing after about 03-04z. && .BOU WATCHES/WARNINGS/ADVISORIES... None. && $$ DISCUSSION...RPK AVIATION...Hiris