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461 FXUS65 KBOU 111759 AFDBOU Area Forecast Discussion National Weather Service Denver/Boulder CO 1159 AM MDT Sat Apr 11 2026 .KEY MESSAGES... - Scattered showersand a couple thunderstorms producing gusty winds this afternoon and early evening. Potential for a few stronger storms in our eastern counties. - Warm and dry Sunday and Monday, with breezy/windy conditions possible along with increasing fire conditions. - Weakening disturbance for Tuesday with a chance of mainly light showers, then dry weather returns for Wednesday and Thursday. && .DISCUSSION /Through Friday/... Issued at 1047 PM MDT Fri Apr 10 2026 SW flow aloft will remain over the area on Sat as a disturbance moves across WY. At the sfc, low pres will extend from ern WY into ern CO. Overall, low level moisture will mix out by aftn, except over the far nern plains where SBCAPE may be up to 1000 g/kg. Further west, SBCAPE will be 500 j/kg or less and over the higher terrain. However, lapse rates will be decent along with quite a bit of mid level moisture. Thus will see higher based showers with a few tstms across the area. DCAPE over the plains will be around 1000 j/kg so a few of the stronger storms may produce marginal svr wind gusts. Highs will be warmer with readings in the 70`s across the plains. On Sun, drier air in SW flow aloft will spread across the area with little chc of pcpn. In addition, winds will increase over the higher terrain and portions of the plains. Highs across the plains will range from 75 to 80 degrees. For Mon, an upper level trough will move in the Great Basin with increasing SW flow aloft as a sfc lee trough extends from ern WY into ern CO. Cross-sections show limited moisture embedded in the flow thru aftn with dry air in the lower levels. As a result, it will be warm and dry over the plains with just a slight chance of aftn showers over the higher terrain. Winds will remain gusty over the higher terrain and portions of the plains. Looking ahead to Mon night into Tue, the upper level trough over the Great Basin will move across as a disorganized system with rather weak QG ascent. Best chc of precip will be in the mtns with just a chc of showers across the plains. Overall amounts with this system look to be on the light side at this time. On Wed, the flow aloft will be zonal with latest cross-sections showing very little moisture in the flow. Thus it looks mainly dry with warmer temperatures as downslope low level flow develops. On Thu, the flow aloft will become more SW as an upper level trough approaches from the Pacific NW. For now, Thu looks dry with above normal temperatures. && .AVIATION /18Z TAFS through 18Z Sunday/... Issued at 1155 AM MDT Sat Apr 11 2026 Winds have been gusting around 15 to 20 knots for the past several hours at KAPA and KDEN. We have quickly warmed this morning to near 70 degrees F at KDEN as of 18z and are starting to see cumulus clouds across Boulder, Jefferson, and Douglas counties. A chance for high-based isolated to scattered showers (30-40%) continues for this afternoon at all three sites. There is a low chance (10%) for an isolated thunderstorm to occur. Therefore, we opted to stick with the -SHRA vs.-TSRA. DCAPE values are expected to be around 700 to 1000 J/kg, but CAPE values should stay below 400 J/kg this afternoon. To account for any gusty outflow winds from these showers, there is a TEMPO and PROB30 for wind gusts of 30 to 40 kts with a low chance (10%) of these gusts exceeding 40 kts. These would generally occur between 20z and 02z this afternoon and evening. We eventually turn to drainage winds this evening between 6 and 12 kts. Tomorrow afternoon, winds will stay S to SW, but will increase with gusts expected to be as strong as 20 to 25 knots starting around 18z at KAPA and KDEN. Skies will be mainly clear tomorrow afternoon with only a few mid-level clouds possible. && .FIRE WEATHER... Issued at 1047 PM MDT Fri Apr 10 2026 Have expanded watch for Sunday to include plains areas near the WY border and across South Park. Winds may end up being borderline in some areas but humidity levels will be low and precip has been minimal. At this time, best chc for stronger winds appears to be over South Park, southern Foothills, Palmer Divide and near the Wyoming border. && .BOU WATCHES/WARNINGS/ADVISORIES... Fire Weather Watch from Sunday afternoon through Sunday evening for COZ214-216-238-239-241-242-246>251. && $$ DISCUSSION...RPK AVIATION...MV FIRE WEATHER...RPK