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909 FXUS65 KBOU 142331 AFDBOU Area Forecast Discussion National Weather Service Denver/Boulder CO 531 PM MDT Wed Oct 14 2026 .KEY MESSAGES... - Cool, cloudy, and drizzly through tonight. - Rain and mountain snow becoming widespread tonight, before winding down on Thursday. - Several inches (4-12") of snow expected for the mountains above9,000 to 10,000 feet with travel impacts tonight and intoThursday morning. Lighter snow and at least a dusting into the mountain valleys and higher foothills. - First freeze of the season expected over most of the plains lateThursday night into early Friday morning. - Drier and warmer again for the weekend and early next week. && .DISCUSSION /Through Wednesday/... Issued at 111 PM MDT Wed Oct 14 2026 Water vapor satelliteimagery shows the upper level low near the Four Corners at this time. It is still forecast to track northeast across Colorado, but models favor a slightlymore northerly track than earlier advertised. We nudged precipitation amounts down slightly because of this track shift.Easterly low level flow continues to produce widespread low clouds and drizzle east to the Continental Divide. This easterly flow is a downslope component west of the divideand satellite imagerycurrently shows mostly sunny skies at this time. As the upper level low nears, ridge top winds turn more southerly, which should cut off the downslope flow. The next batch of lift and precipitation is over south central Colorado and will lift northeast, bringing rain and mountain snow late this afternoon and evening. Then overnight as the low shifts over northeast Colorado, northwest flow (more typical) is expected to leadto orographic lift in addition to the deformation zone. Meanwhile, eastern Colorado is expected to see a lull in precipitation, except for continued drizzle. The deformation zone shifts east over northeast Colorado bringing rain showers. The heaviest rainfall amounts and best chance for rain will be over the northern part of the state. If the more northerly low trend continues, areas along and south of I-70 may see very little additional precipitation Thursday. Rain and mountain snow will end Thursday afternoon as the upper level low weakens and moves east of the area. The remnants of the upper level low will be northeast of the State by Thursday evening. Much drier air will move into the area leading to clearing skies during the evening. This will lead to good radiational cooling and a chilly overnight period Thursday night/Friday morning. Most locations are expected to see a frost or hard freeze therefore, we have issued a freeze watch for Thursday night and into Friday morning. We maintain a northwest flow aloft on Friday as a ridge develops to our west and a trough to our east. Surface high pressure over Colorado will lead to a sunny day with light winds and cool temperatures for Friday. Highs will be slightly below normal with readings in the mid to upper 50s. The ridge to the west moves over Colorado Saturday and we see ridging continue through Monday. A weak trough passes through the ridge on Sunday. There`s enough moisture for clouds, but not enough for precipitation. So we may see a slight dip in temperatures Sunday with the increase in cloud cover. Highs are expected to be in the 70s Saturday through Monday, with some upper 60s possible Sunday if cloud cover persists for much of the day. Southwest flow aloft is expected for Tuesday and Wednesday as a strengthening trough along the west coast pushes the ridge east of the region.Temperatures will continue to run above normal under this pattern with dry conditions persisting. This trough along the west coast is the next system to watch for precipitation acrossour area late next week. && .AVIATION /00Z TAFS through 00Z Friday/... Issued at 516 PM MDT Wed Oct 14 2026 Showers will be likely (70 percent) thru 05z with visibility down to 2-5sm with the heavier rain. Ceilings will remain generally blo 1000 ft. From 05z thru 11z expect periods of ceilings below 500 ft with areas of fog and drizzle with visibility if 1-3sm. There is a chance (30 percent) of lower visibility down to 1/2sm in fog, especially at BJC for a few hours. Winds early this evening will be east at DIA with NE winds at BJC and variable directions at APA. Eventually winds will become more N/NNE by 05z which will continue overnight. On Thu, there will be a period of rain between 14z and 18z with visibility down to 5sm at times times. Ceilings will be in the 1200 to 1500 ft range with and may drop below 1000 ft for a few hours. After 18z rain chances should gradually decrease. By 22z or 23z ceilings should gradually sct out. As far as winds, they will be from the north and gradually increase by 14z with gusts up to 30 mph through the aftn. Winds should gradually decrease by 23z. && .BOU WATCHES/WARNINGS/ADVISORIES... Winter Weather Advisory until 6 AM MDT Thursday for COZ031-033- 034. Freeze Watch from late Thursday night through Friday morning for COZ038>051. && $$ DISCUSSION...BM AVIATION...RPK