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867 FXUS65 KBOU 120555 AFDBOU Area Forecast Discussion National Weather Service Denver/Boulder CO 1155 PM MDT Sat Apr 11 2026 .KEY MESSAGES... - Critical fire weather conditions expected both Sunday late day and Monday late day over the southern forecast area and the plains near the Wyoming border. - Continued above normal warmth Sunday and Monday with a few, mainly alpine late day showers. - The next system will bring cooler temperatures and a decent chance of precipitation to the forecast area Tuesday and Tuesday evening. && .DISCUSSION /Through Saturday/... Issued at 1155 PM MDT Sat Apr 11 2026 The convection has ended across the CWA late this evening. Drainage winds are in place across the forecast area. Temperatures were still in the 50s over the plains at this time and even a tad warming to decent downsloping winds near the foothills. Southwesterly flow aloft will dominate our weather now through Tuesday night. Jet level wind speeds increase by Sunday night and continue pretty strong, 90-110 knots, through late Tuesday. By then, upper level troughing is expected to move across Colorado Tuesday night through Wednesday morning. There isn`t much in the way of synoptic scale energy through Monday. The QG Omega fields have decent upward motion starting late Monday overnight into Tuesday with the approaching trough. There is also a cold front for the CWA Tuesday afternoon and evening. Moisture is looking scarce for late day Sunday. Will keep the 10-20% pops going for the mountains late this afternoon and evening. There will be a little better moisture in the mountains for late day Monday, so pops will be as high as 40%. Will increase pops late Monday overnight and Tuesday with the approaching trough`s incoming synoptic scale energy and increased moisture. The latest model runs point to most of the CWA actually getting measurable precipitation on Tuesday and Tuesday evening. For temperatures, highs will be well above seasonal normals both Sunday and Monday. Sunday`s highs will be in the mid to upper 70s over the plains. Monday`s highs look a tad cooler with lower to mid 70s for highs there. Tuesday`s expected cooler airmass keeps highs in the 60s over the plains and this continues on Wednesday. For the later days, Thursday through Sunday...there is more southwesterly flow aloft Thursday into Friday. This is followed by a fairly strong upper trough, complete with a decent shot of cold air, low level upslope flow and the potential for snow over much of the CWA from later Friday, Friday night on into Saturday. We`ll see. && .AVIATION /06Z TAFS through 06Z Monday/... Issued at 1155 PM MDT Sat Apr 11 2026 VFR conditions will persist through the period. No showers or thunderstorms are forecast, although we will see some high based cumulus. The threat of any variable gusty outflow winds from those 22Z-02Z would be less than 10%. Winds are starting from the W-NW, although they are now weakening as that was the last of outflow associated with dissipating showers in the mountains. Winds are then expected to settle and be more SW overnight through at least 18Z Sunday. After 18Z, we`ll see stronger mixing but there remains some uncertainty in direction without strong downward forcing. We do think the mixing will be sufficient for a few SW-W gusts to 20-22 kts after 20Z (slightly earlier at KAPA). However, there`s a 30% chance winds stay lighter and even retain a more S-SE component in the afternoon. Winds will eventually return to more S-SW by 03Z-05Z Monday. && .FIRE WEATHER... Issued at 1137 PM MDT Sat Apr 11 2026 We went with a Red Flag Warning Sunday afternoon into early evening for the southern CWA Zones and Zone 238 due to the low humidity levels and wind gusts to 30 mph. Fuels remain extremely dry in these areas. We also went with the Fire Weather Watch over similar areas for Monday afternoon and early evening, due to the same conditions. There looks to be elevated to critical fire weather conditons Thursday afternoon as well. && .BOU WATCHES/WARNINGS/ADVISORIES... Red Flag Warning from noon to 8 PM MDT Sunday for COZ214-216-238- 241-246-247-249. Fire Weather Watch from Monday morning through Monday evening for COZ214-216-238-241-242-246-247-249. && $$ DISCUSSION...66 AVIATION...20 FIRE WEATHER...66