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710 FXUS65 KBOU 020839 AFDBOU Area Forecast Discussion National Weather Service Denver/Boulder CO 239 AM MDT Wed Sep 2 2026 .KEY MESSAGES... - A chance for showers and thunderstorms in the northern Mountains today with gusty winds. A slight chance of showers and a few thunderstorms across the plains late this afternoon and evening. - Warmer Thursday and Friday with mainly dry conditions. - Return of better moisture by the weekend with an increasing chance for showers and thunderstorms across the high country. && .DISCUSSION /Through Tuesday/... Issued at 233 AM MDT Wed Sep 2 2026 Drier air in SW flow aloft will remain in place across the area today. However, there is a decent upper level jet over the area which will combine with decent lapse rates and lingering moisture, to produce a chance of showers/tstms over the higher terrain, mainly north of I-70. With decent mid level flow, gusty winds will accompany this activity as well. Meanwhile, along northern areas of the I-25 Corridor, will see sct high based showers along with a possible tstm by late aftn. DCAPE is around 1000 j/kg so brief gusty outflow winds will occur with this activity as well. For tonight, the upper level jet will move slowly across the plains which may lead to an additional chc of higher based showers and a few tstms thru the evening hours. As for highs today, readings will rise into the upper 80`s to lower 90s over the plains. On Thu, SW flow aloft will continue but it appears an even drier airmass will be in place. Thus don`t expect any shower/tstm activity. Temps will continue to warm with readings rising into the lower to mid 90`s across nern CO. By Fri, the flow aloft will become more SSW. Some monsoon moisture could get entrained into the flow. At this point, still think any shower/tstm activty in the aftn/evening will be widely sct. Once again highs will reach the lower to mid 90`s over nern CO. For the weekend, models still show an upper level trough over the wrn US with an upper level high extending from the srn Rockies into the central US. As a result, this will leave SSW flow aloft across the area as some monsoon moisture moves across the area. It`s not certain how deep this moisture will be initially. Specific Humidity is in the 5-6 g/kg range on Sat and then increases to 7-8 g/kg on Sun. Thus, activity on Sat may be rather high based and more sct as compared to Sun which may have better coverage. Meanwhile, it still appears highs will remain above normal both days with more 90`s possible over nern CO. By Labor Day, the upper level trough over the wrn US is fcst to move northeast across the nrn Rockies. As a result, this leaves nrn CO in SW flow aloft. Models continue to show monsoon moisture embedded in the flow with specific humidity from 6-8 g/kg. Thus will keep in a good chc of showers/tstms. Highs still look to remain above normal across the plains. For Tue and Wed, there are some disagreements between the ECMWF and GFS. The ECMWF has more of a zonal component developing as monsoon moisture is shifted southward. Meanwhile, the GFS keeps SW flow aloft across the area with a continued influx of monsoon moisture. Thus, the ECMWF would have drier conditions both days while the GFS would have a chc of showers/tstms. && .AVIATION /06Z TAFS through 06Z Thursday/... Issued at 1109 PM MDT Tue Sep 1 2026 Winds will gradually go drainage by 07z and continue overnight. On Wed, winds will become more SE by 19z. Latest data suggest there will be sct high based -shra by 22z with a 10 percent chc of -tsra. DCAPE values are around 1000 j/kg so expect gusty and erractic outflow winds thru early Wed evening. Winds may shift to more northerly by 00z and then to easterly by 04z. && .BOU WATCHES/WARNINGS/ADVISORIES... None. && $$ DISCUSSION...RPK AVIATION...RPK