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050 FXUS65 KBOU 022001 AFDBOU Area Forecast Discussion National Weather Service Denver/Boulder CO 201 PM MDT Thu Jul 2 2026 .KEY MESSAGES... - Critical fire weather conditions in South Park today and Friday. - Isolated showers and storms will form mainly over east-central Colorado this afternoon and evening. A couple storms may be strong to severe. - Near normal temperatures with scattered showers and storms on July 4th. These storms could become strong to severe. && .DISCUSSION /Through Thursday/... Issued at 1231 PM MDT Thu Jul 2 2026 As of 2pm this afternoon, there`s a boundary extending southeast from south of Denver through Douglas and Elbert counties and into southern Lincoln. Higher moisture and east/southeast winds are to the north of the boundary and drier south/southwest winds are to the south of the boundary. We`re already seeing some cumulus and a thunderstorm develop along this boundary. Additional development will be possible along this boundary into the late afternoon, with activity then progressing to the northeast. Storms today should remain relatively isolated. The most likely areas to see storms today will be our southern and eastern counties, with a chance for an isolated storm to move off the foothills and into the northern I-25 corridor. Surface instability and shear along the boundary could produce a landspout or two with any storm that initiates along it. We`re also looking at the potential for large hail and strong winds with any storm that develops. Temperatures will increase for Friday as the upper level ridge builds over the area. A weak upper level disturbance looks to move near/north of the area Friday late afternoon and evening. This combined with the potential for some residual outflow boundaries from overnight convection to our north/northeast could trigger some isolated convection. Most of the convection is expected to remain to our north, however we could be on the tale end of the activity, with a few storms pushing out of Wyoming and into our northern counties. There`s still quite a bit of uncertainty with the location and extent of the convection on Friday due to the overnight activity tonight to our north, and it`s impact to the afternoon convection in our area tomorrow. Outflow from convection on Friday and more easterly surface winds as a surface low moves near the area will bring increased moisture and higher dewpoints for Saturday. The easterly/southeasterly winds will allow for upslope flow, potentially triggering some showers and thunderstorms in the early to mid afternoon, with storms progressing east into the evening. The east/southeast surface winds and westerly winds aloft will create decent 0-6km shear across the area. This combined with strong lapse rates could lead to severe weather Saturday afternoon and evening. The main hazards will be large hail, strong winds, and dangerous lightning. Upper level ridging will build over the area Sunday into early next week, bringing temperatures into the low to mid 90s across the plains. Even with the strengthening ridge, a few upper level disturbances are expected to move through the flow aloft, bringing the potential for isolated showers and storms each afternoon Sunday and Monday. The ridge will start to push eastward on Tuesday, flattening a bit as a more potent shortwave moves through. This shortwave will provide the potential for more widespread rain Tuesday afternoon and evening. && .AVIATION /18Z TAFS through 18Z Friday/... Issued at 1151 AM MDT Thu Jul 2 2026 Winds are just now transitioning to diurnal easterlies, and should gradually strengthen with a shear zone/weak cyclone developing south of the TAF sites. Peak gusts could reach 20-22 kts. There is already some high based cumulus southwest of the TAF sites, and given that we expect some isolated virga we`ve introduced a PROB30 of VRB gusty outflow winds. DCAPE is nearly off the charts given the deep and dry subcloud layer, reaching 1600-1700 J/kg so potential for very localized gusts to 50 kts if we fully mix, but that`s also the greatest uncertainty as we`re still quite stable with delayed heating after last night`s surge. Winds may very well become VRB for a few hours 03Z-06Z if we get any convective influence, but will otherwise lean toward a fairly normal diurnal wind progression from SE-SSW-WSW 03Z-12Z Friday. Then back to a diurnal easterly around 18Z-19Z Friday. Next concern is smoke impacts. We still have marginal IMC conditions at the start of this TAF period, but additional smoke will arrive from the wildfires in southwestern Colorado and southeast Utah. With the change in trajectories, smoke concentration will be greater than the last few days and thus could actually start impacting visibility down to ~6SM at times through 18Z Friday. && .BOU WATCHES/WARNINGS/ADVISORIES... Red Flag Warning until 8 PM MDT this evening for COZ214. Red Flag Warning from noon to 7 PM MDT Friday for COZ214. && $$ DISCUSSION...AP AVIATION...20