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063 FXUS65 KBOU 051243 AFDBOU Area Forecast Discussion National Weather Service Denver/Boulder CO 543 AM MST Thu Mar 5 2026 .KEY MESSAGES... - Warm Thursday, with critical fire weather conditions across the Palmer Divide and Lincoln County in the afternoon. - Moderate to locally heavy snow is expected to impact the mountains and foothills Thursday night through Friday. - A few inches of snow increasingly likely for most of the lower elevations, favoring minor impacts. Continued uncertainty makes the forecast especially dynamic, and potential for locally moderate travel impacts does exist for portions of the I-25 corridor from Denver southward to the Palmer Divide and portions of the northeast plains. - Warmer and drier Saturday through Monday. Windier conditions develop as early as Tuesday && .DISCUSSION /Through Wednesday/... Issued at 1104 PM MST Wed Mar 4 2026 Will have one more mild day before a significant change occurs Thu night through Friday. SW flow aloft will be across the area on Thu as sfc low pres extends from near Denver into sern CO. This will allow for gusty south winds across the Palmer Divide and east central Plains. Highs across the plains will be from 65 to 70 degrees. For Thu night into Fri, an upper level trough will move from the Great Basin into Colorado with a closed low over swrn CO by 12z Fri. This low is fcst to move northeast and be over swrn NE by early Fri evening. Models show favorable QG ascent across the area on Fri which moves northeast of the area Fri night. Low level winds will become northeast Thu night and then more northerly by 12Z Fri. Snow will gradually increase in the mtns late Thu night and then spread across the plains on Fri. Snow will continue into Fri evening and then decrease by midnight in most areas. As far as snow amounts, mtn areas along and east of the divide should receive heavy snow. In addition, there is some potential for heavier snow across the srn foothills where N to NNE low level flow is enhanced. Currently have an advisory out but this may need to be upgraded to a warning if the trend for heavier snow continues in later model runs. Furthermore, may need an advisory across the Palmer Divide as this area will do well with northerly low level flow. Across the plains, if low level flow does become more northerly by 12z Fri then snow amounts along nrn areas of the I-25 Corridor and across the plains closer to the WY-NE would be only an inch or so. In the Denver Metro area, amounts from 2 to 4 inches will be possible. If the upper level low is more organized than expected, this could lead to a band of heavier snow just to the N and NW of its track across portions of the plains from east of Denver towards the Akron area. By late Fri night into Sat the upper level trough will move northeast of the area with drier air moving in. As a result, will see dry conditions on Sat with temps near seasonal levels. On Sun, dry NW flow aloft will be over the area as a sfc lee trough develops. This will allow for downslope low level flow, with warmer temperatures, as highs rise into the 60`s across the plains. Looking ahead to Mon and Tue, the flow aloft will be mainly westerly with cross-sections showing only some mid and higher level moisture embedded in the flow. Thus should see above normal temperatures with mainly dry conditions both days. && .AVIATION /12Z TAFS through 12Z Friday/... Issued at 538 AM MST Thu Mar 5 2026 VFR conditions expected through this evening. Relatively light winds this morning will give way to stronger winds this afternoon. The wind direction will be challenging to forecast. A DCVZ will setup over the city of Denver. This will likely create gusty southerly winds for DEN and APA while northeast winds occur at BJC. However, there is a 30% chance that winds at DEN never end up turning to the south. The DCVZ has a chance to develop south of DEN and create northeast winds there during the afternoon. Winds will likely turn to the northeast at DEN and BJC during the late afternoon/early evening hours. A strong cold front will move through the terminals around 03-05Z tonight. This front could have winds up to 40 knots behind it. Ceilings will decrease and around 09-12Z on Friday as precipitation, likely in the form of snow, will develop across the terminals. This snow could be intense, especially after 12Z, with visibility down to a half mile for a short time and ceilings below 500 feet at all terminals. Snow will decrease in intensity in the afternoon and ceilings and visibility will increase as a result. && .FIRE WEATHER... Issued at 1104 PM MST Wed Mar 4 2026 South to southwest winds will increase on Thursday in advance of the incoming storm system. Downslope flow off the Palmer Divide will result in warm and dry conditions, with humidity falling into the 10-15% range. Mixing heights should be quite elevated, and help promote efficient mixing of winds aloft down to the surface. The stronger flow aloft, however, likely won`t arrive until later in the afternoon, thereby shortening the window of critical conditions slightly (mainly mid and late afternoon), when gusts 25-30 mph will be most likely. Tuesday`s wetting rains were rather localized and not widespread across the warned zones, so fuels were deemed susceptible. && .BOU WATCHES/WARNINGS/ADVISORIES... Winter Weather Advisory from midnight tonight to 8 PM MST Friday for COZ031. Winter Storm Warning from midnight tonight to midnight MST Friday night for COZ033-034. Winter Weather Advisory from midnight tonight to midnight MST Friday night for COZ035-036. Red Flag Warning from noon today to 6 PM MST this evening for COZ241-246-247. && $$ DISCUSSION...RPK AVIATION...Danielson FIRE WEATHER...RPK