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264 FXUS65 KBOU 140044 AFDBOU Area Forecast Discussion National Weather Service Denver/Boulder CO 544 PM MST Fri Nov 13 2026 .KEY MESSAGES... - Above normal temperatures and dry conditions will prevail today, followed by more seasonable temperatures this weekend into next week. - Chances for rain and snow showers across the high country Saturday, with a few showers possible over the eastern plains. - A more active storm track looking likely for next week. && .DISCUSSION /Through Friday/... Issued at 138 PM MST Fri Nov 13 2026 The persistent upper-level ridge that has been parked over the region, keeping above-normal temperatures and dry conditions in place, is finally beginning to shift eastward today. This will establish a more favorable storm track for approaching systems, essentially opening the door to a more active weather pattern heading into next week. The first of what looks to be three separate disturbances expected to move across the western CONUS this week can be seen on water vapor imagery as an open trough moving through SoCal and Arizona early this morning. As this approaches, we will see a transition to southerly flow aloft over Colorado as the day progresses. Today`s afternoon high temperatures are on track to reach the low to mid 60s across the plains, outside of where morning fog has limited the sun from heating things up so far today. Therefore, areas in our far northeastern corner and Lincoln County will be slightly cooler than our more densely populated areas along the urban corridor, where only some high cirrus are in place. Our mountain valleys should see temperatures warm into the low to mid 50s. Moisture is expected to increase overnight tonight as the trough nears, bringing an increase to cloud cover as the night progresses. Across the lower elevations, fog is expected to develop late tonight that may make for some hazardous driving conditions through the morning on Saturday, and may lead to some impacts at DIA with decreased arrival and departure rates possible for those with early morning flights. Overnight low temperatures are forecast to drop into the 30s across the plains, 20s for the higher elevations. Light mountain snow showers are expected to develop through the morning tomorrow, with scattered rain showers forecast to move over the plains for the afternoon and overnight as latest guidance shows the trough closing off and becoming a closed low over southeastern Colorado. Snow amounts are not expected to be very impressive with this first round of moisture, but a few inches (1-3") are expected for elevations above 10,000 feet, with less than an inch forecast for our mountain valleys. Areas over the Palmer Divide and into Lincoln County will cool enough overnight Saturday that we may end up with some flakes falling before sunrise on Sunday, with the best chance for any light accumulations to be over the Palmer Divide. Fog is expected to develop again late Saturday night across Lincoln County before spreading northward across the eastern plains and along the urban corridor, where it will gradually burn off through the morning on Sunday. Outside of the morning fog, quiet weather is expected to return across the forecast area for Sunday afternoon, where temperatures are expected to warm back up into the mid to upper 50s across the urban corridor. A brief period of upper-level ridging is expected to return over the region on Monday that will bring a slight warmup and drier conditions for the first few days of next week. By midweek, a second disturbance is expected to approach the Intermountain West, though ensemble guidance continues to show considerable spread and little consensus. This is evident in all of the GEFS/AIFS-ENS/AIGEFS spaghetti plots, where 500mb height contours look more like an actual plate of spaghetti than a clear lock on any particular outcome. The same can be said for the third potential disturbance that may arrive by the end of next week. While confidence remains low at this time, this system has the potential to be the most impactful of the three, bringing a more substantial cooldown and perhaps even our first accumulating snowfall across the lower elevations. There is still much to unpack, so stay tuned! && .AVIATION /00Z TAFS through 00Z Sunday/... Issued at 543 PM MST Fri Nov 13 2026 Winds are holding to the northwest at KDEN, and are expected to stay predominantly west/northwest for the next couple hours before becoming south/southwesterly for much of the overnight period. By around 11Z, winds should once again become northwesterly, and fog will settle over KDEN and KBJC. At KBJC, confidence is high (80%) for 1/4SM visibility from around 11-17Z. At KDEN, there`s a 70% chance for 1/4SM visibility fog starting at either 11Z or 12Z and ending anytime between 16-18Z. Confidence is low (20%) for fog to reach as far south as KAPA. Winds should remain light and north/northeasterly throughout most of the afternoon on Saturday, becoming more easterly after 20Z. Rain chances increase after 21Z for KDEN and KAPA Saturday evening, though any showers will be light and scattered in nature. While KBJC could also see some scattered showers, precip chances are higher after 00Z. && .BOU WATCHES/WARNINGS/ADVISORIES... None. && $$ DISCUSSION...9 AVIATION...AGS