National Weather Service Forecast Discussion |
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465 FXUS65 KBOU 171932 AFDBOU Area Forecast Discussion National Weather Service Denver/Boulder CO 132 PM MDT Tue Mar 17 2026 .KEY MESSAGES... - Significant warm and dry period through Saturday. All-time new March record high temperatures a good bet for the plains Thursday, Friday and Saturday. - Record high temperatures and low humidity levels will sustain prolonged high fire danger for portions of the plains today and Wednesday, then across much of the forecast area Thursday through Saturday. && .DISCUSSION /Through Tuesday/... Issued at 120 PM MDT Tue Mar 17 2026 The forecast continues to indicate well above normal record warmth, no precipitation and critical fire weather conditions for the next several days. West and northwesterly low level winds are in place across much of the forecast area at this time. Gusts of 20 to 30 mph are noted across the northern border plains with 10 to 20 mph elsewhere. The light snow over the higher elevations is over. Models keep a strong upper high centered over the southwestern U.S. through Friday and even further out into the weekend. For our forecast area, models have fairly strong north-northwesterly flow aloft for the CWA today through Wednesday night. From Thursday through Friday, speeds decrease at jet level and the direction is more due northwesterly. The QG Omega fields have benign synoptic scale energy for the CWA through Friday. For moisture, cross sections just show a tad in the upper levels for the next four days. There is no precipitation progged on the QPF fields through Friday. For temperatures, 850mb, 700mb and thickness fields all show readings to set new daily record highs Thursday, Friday and Saturday with low to mid 80s all three days. It still looks likely that Denver will see a new all-time March high temperature as well; one or even two of those days. Denver`s record high reading for March is 84 degrees. It was set back on March 26, 1971. All the heat and low humidity levels will make elevated and critical fire weather conditions. For the later days, Saturday through Tuesday, models continue to show the upper ridge center to weaken and push southward into Mexico Saturday night and Sunday. There looks to be flat upper ridging for the forecast area all four days. A weak cold front is still progged to push into the CWA Saturday night, with Sunday`s highs cooling into the 60s over the plains. Readings warm right back up with mid 70s over the plains by Tuesday. There may be enough moisture in the westerly flow for light scattered snow showers over the high mountains Sunday through Tuesday && .AVIATION /18Z TAFS through 18Z Wednesday/... Issued at 1151 AM MDT Tue Mar 17 2026 VFR conditions will persist through the period. Daytime heating and mixing is increasing the winds, with W-NW G22-30kts expected at the Denver metro TAF sites from now through about 01Z. Then mixing will decrease with the loss of daytime heating and allow winds to relax. However, they will likely be slower than normal to return to normal drainage winds due to a modest gradient still in place, and and a slight chance (20%) that a few gusts to 20 kts occur til around 05Z. After that, an eventual transition to SSW is expected at KDEN and KAPA, only to increase again from the W-NW toward 18Z Wednesday, although a couple knots weaker than today. Despite less mixing overnight, KBJC will still have a chance (30-50%) of occasional G25-30kts in the 01Z-15Z period due to proximity to the mountains. && .FIRE WEATHER... Issued at 111 PM MDT Tue Mar 17 2026 Will leave the Red Flag Warning going over the northern and northeastern plains until early evening. Current wind gusts are strong enough across the norther border zones to meet the Red Flag criteria. For Wednesday will go with another Red Flag Warning for most of the plains, with the exception of the southern tier of zones. Humidity levels will drop into the 8-13 percent range during the afternoon hours. Wind gusts will be marginal in some areas, but close enough with the dryness of the fuels in mind across those areas. Concerning the foothills, fuels are not yet at critical levels for widespread fire growth in those areas according to latest data from land managers. && .BOU WATCHES/WARNINGS/ADVISORIES... Red Flag Warning until 8 PM MDT this evening for COZ238-242>244- 248>251. Red Flag Warning from 11 AM to 7 PM MDT Wednesday for COZ238>240- 242>245-248>251. && $$ DISCUSSION...66 AVIATION...20 FIRE WEATHER...66