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011 FXUS65 KBOU 082333 AFDBOU Area Forecast Discussion National Weather Service Denver/Boulder CO 533 PM MDT Wed Apr 8 2026 .KEY MESSAGES... - Scattered showers Thursday afternoon/evening. Rainfall amounts will be light (less than 0.10"). - A brief cool down Friday with a 20-30% chance for light rain. - Warm and mostly dry for the weekend. Scattered showers possible Saturday, mainly over the mountains. Dry Sunday. - A spring storm possible Tuesday/Wednesday with heavier precipitation amounts possible. && .DISCUSSION /Through Wednesday/... Issued at 201 PM MDT Wed Apr 8 2026 Cold front has back southwestward much quicker thanthe models indicated. High temperatures lowered a few degrees earlier for areas behind the front. Isolated, high-based showers are still on track for this afternoon and early evening. Low level moisture increased behind the front, but it`s shallow and won`t help with wetting rainfall. Chances for measurableprecipitation remain low, less than 10 percent. Gusty outflow winds up to 30 mph will be possible under and near the high-based showers. Thursday`s forecast is tricky regardingPoPs. We have an upper level ridge building over the region, but it appears a weak wave passes underneath it. This combined withsteep lapse rates is expected to result in scattered showers during the afternoon and evening. A weak front tracks southward duringthe evening, which could increase activity. Moisture is again limited, so any rainfall reaching the ground is expected to be light, with precipitationamounts less than a tenth of an inch, and in most cases less than 0.05 (in).Gusty outflow winds around 35 mph will be possible with the showers. Northeast low level flow behind the front continues to increase low level moisture through Thursday night. Low clouds (and possibly drizzle and fog) are expected to develop over the eastern plains late Thursday night and into Friday morning. It will be cooler Friday over the northeast plains where low clouds are expected to persist through the day. Gusty south to southeast winds will develop over eastern Colorado. This should lead to the development of a Denver cyclone. Northerly flow on the backside of it will pull cooler air southwestward, so northern parts of the I-25 corridor may struggle to reach 60 degrees. Another round of high-based isolated/scattered showers will be possible during the afternoon, though any rainfall will likely be light. On Saturday, southwest flow aloft will prevail. A lee-side surface trough forms over eastern Montana, eastern Wyoming, and far northeast Colorado. This, combined with the increasing southwest flow aloft will lead to gusty south winds. A shortwave trough embedded in the southwest flow aloft lifts northeastward across the central Rockies. Given the current projected track, western and centralColorado will see scattered to numerous showers with this system. Farther east, scattered high-based showers are expected for the Front Range and eastern plains. Temperatures rebound under this pattern with highs reaching the 70s across northeast Colorado. Southwest flow aloft continues Sunday around an upper level low slowly moving east across northern California. Subsidence behind Saturday`s system will prevail bringing dry conditions to the area. Isolated high- based showers are possible over the higher terrain during the afternoon, but little to no rainfall is expected. South to southwest winds are expected to increase during the day as flow aloft increases. Depending on the strength of the winds and how low relative humidity falls, fire weather may be a concern. Temperatures remain warm with highs expected to reach the 70s again. For Monday through Wednesday, the upper level low to the west will slowly progress eastward. Southwest flow aloft continues Monday ahead of the system. Moisture begins to increase with a the best chance for showers over the mountains. The best chance for precipitation with this system comes Tuesday as it tracks across the Four Corners. There is still considerable uncertainty regarding this system as models vary on the strength, timing, and track. However, models generally agree that this upper level low will track over or near the Central Rockies on Tuesday. A subset of the ensemble still shows it cold enough for snow across the lower elevations. The chance for precipitation decreases Wednesday as the upper level low is expected to move east of the region. Temperatures begin to recover with highs reaching the 60s across northeast Colorado. && .AVIATION /00Z TAFS through 00Z Friday/... Issued at 527 PM MDT Wed Apr 8 2026 VFR conditions are expected to prevail for all terminals through the TAF period. Gusty winds have largely subsided at this hour, and winds will continue to veer E to SE to S through the evening at KDEN/KAPA with drainage flow continuing overnight. KBJC will be light and VRB during this period. Daytime mixing is expected to favor development of relatively light 08-11kt NE/NNE winds beginning 18-19Z Fri at all of the terminals. Between 19-20Z, mid-level cumulus development and associated virga and -SHRA is anticipated, with this scattered activity persisting through at least 01Z, and possibly as late as 03Z, being most numerous and consistent in the vicinity of KDEN and KBJC, for which TEMPO groups have been introduced. Convective-induced gusts of 18-22 kts will be possible with and near passing -SHRA. An isolated TS cannot be ruled out with marginal instability in place. With the bulk of the activity expected to favor the northern half of our forecast area, wind directions should thus tend to favor NW/N/NE components, but some variability is likely nonetheless. && .BOU WATCHES/WARNINGS/ADVISORIES... None. && $$ DISCUSSION...12 AVIATION...BRQ