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628 FXUS65 KBOU 180607 AFDBOU Area Forecast Discussion National Weather Service Denver/Boulder CO 1207 AM MDT Tue Aug 18 2026 .KEY MESSAGES... - Scattered showers and thunderstorms expected Tuesday and Wednesday. Isolated severe thunderstorm threat both afternoons and evenings. - Above normal temperatures through the weekend. Drier Thursday and Friday, but some monsoonal moisture likely returns by the weekend. && .DISCUSSION /Through Monday/... Issued at 125 PM MDT Mon Aug 17 2026 Drier zonal flow aloft is now over most of the state today... and unsurprisingly that has led to warmer temperatures across the region, along with far less convection over our forecast area. We`ve seen a return to 90s today (92F at DEN so far), with dew points back down into the 30s across the metro. We haven`t completely mixed out the boundary layer moisture across the northern I-25 corridor and over the easterly plains, where there are still mid/upper 50s dew points and modest MLCAPE. Guidance still tries to spit out a couple of showers or thunderstorms there and the environment would support a couple of stronger storms assuming we get a real attempt at CI at some point this afternoon. A weak cold front is still on track to arrive sometime late Tuesday morning, which should introduce some better surface moisture to the I-25 corridor. The increased instability (along with increasing deep layer shear) will promote at least widely scattered thunderstorms, and it wouldn`t be surprising to see a couple strong to severe storms yet again during the afternoon... especially over the eastern plains. Stronger ridging is expected to develop during the latter half of the week, though we won`t see temperatures climb nearly as high as we did with our previous ridge. Forecast highs will return back into the mid 90s for the Denver metro with generally dry conditions. As we head into the weekend or early next week, the ridge is expected to briefly weaken and shift into a slightly more favorable location for monsoon moisture to make a brief return. Both Sunday and Monday have higher PoPs, though once again the NBM is likely a bit too bullish with PoP coverage across most of our forecast area. && .AVIATION /06Z TAFS through 06Z Wednesday/... Issued at 1145 PM MDT Mon Aug 17 2026 Drainage winds will generally prevail for the next couple of hours. Winds will start to turn more west/northwest around 08Z to 09Z, before becoming variable around 15Z to 16Z. Light and variable winds will continue for the late morning to early afternoon until stronger northeasterly winds move into the area behind a weak cold front. Scattered showers and thunderstorms are expected this afternoon. Uncertainty is still pretty high in both coverage and location of this activity, so we`ve left the prob30 in there for now. But, we may need to update that to a TEMPO if models continue to trend up with storm coverage Tuesday afternoon and evening. There`s also a question on how long the showers and storms will linger across the area before moving off to the east/southeast, with some models keeping them around into the early overnight hours. && .BOU WATCHES/WARNINGS/ADVISORIES... None. && $$ DISCUSSION...Hiris AVIATION...AP