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715 FXUS65 KBOU 030009 AFDBOU Area Forecast Discussion National Weather Service Denver/Boulder CO 609 PM MDT Wed Sep 2 2026 .KEY MESSAGES... - Scattered showers and isolated thunderstorms late this afternoon and evening, mainly north of I-70. - Warmer Thursday and Friday with mainly dry conditions. - Return of better moisture by the weekend with an increasingchance for showers and thunderstorms. && .DISCUSSION /Through Wednesday/... Issued at 141 PM MDT Wed Sep 2 2026 Southwest flow aloft will persist and increase this evening. A shortwave trough will lift northeast across the Great Basin and into the Northern Rockies. At the base of thetrough a 90-110 knot jet will prevail. Lift from the jet produced thunderstormsthis morning over southern Utah. Expect lift from the right entrance region to trigger scattered showers and isolated thunderstorms late this afternoon and more so this evening. Instabilitywill be limited (less than 500 J/kg), as will moisture. Dew points will only be in the 30s to lower 40s, but mid-level moisture will be better. A brief period of moderate rain is possible, but overall precipitation is expected to be light. For Thursday through Sunday, there will be a longwave trough will cover the northwest part of the country and an upper-level high will sit over the southeast. This will result in a southwest flow aloft over Colorado. Temperatures will run above normal under this pattern with highs in the upper 80s to mid 90s each day. Dry conditions are expected Thursday with precipitable water values slightly below normal. Moisture will slowly increase each day. For Friday isolated showers and thunderstorms will be possible over the higher terrain. Saturday will see a slight chance for showers and storms spreading east onto the nearby plains. By Sunday, precipitable water values reach 140-180 percent of normal. This increase in moisture is expected to produce a round of scattered afternoon/evening thunderstorms. For next week, the overall pattern over Colorado changes little as southwest flow aloft persists. The biggest question mark will be how much moisture lifts northward into the region. Models generally place us on the edge of the better moisture, leading to an uncertain forecast. Scattered afternoon/evening showers and thunderstorms look possible each day at this time, but a slight shift in the pattern could bring much drier air into the region. Temperatures are expected to stay above normal with highs in the mid 80s to lower 90s. && .AVIATION /00Z TAFS through 00Z Friday/... Issued at 606 PM MDT Wed Sep 2 2026 Current radar imagery shows a few light showers north of the Denver metro as well as over the foothills. As such, an outflow boundary is already visible and moving into the vicinities of KDEN and KAPA from the NW/NNW. The current cyclone positioned south of KAPA makes forecasting the arrival of this boundary a bit difficult given its interaction with persistent easterly winds. Showers will continue to be able to produce erratic outflows and wind gusts up to 30KT. Once showers exit the area, winds this evening will gradually transition to the SE (~05Z) before becoming southerly during the overnight hours and through mid-morning. Model guidance is all over the place regarding wind direction Thursday afternoon given the possibility of another cyclone developing somewhere near KDEN. At this time, the most likely direction seems to be a NE/ENE wind at KDEN and KBJC. However, the exact location of the cyclone will ultimately determine the evolution of winds at the three airports. An isolated shower is possible in the early evening hours (15% chance). && .BOU WATCHES/WARNINGS/ADVISORIES... None. && $$ DISCUSSION...BM AVIATION...AA