National Weather Service Forecast Discussion |
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167 FXUS65 KBOU 150019 AFDBOU Area Forecast Discussion National Weather Service Denver/Boulder CO 619 PM MDT Tue Apr 14 2026 .KEY MESSAGES... - Numerous rain showers with snow showers above 7000-8000 feet MSL will continue through this evening. Rain showers linger overnight across the northeast plains. - Locally critical fire weather conditions over the plains Thursday afternoon. - Next system moves in Friday with much colder temperatures and snow for most locations. - Hard freeze likely Friday night and into Saturday morning with lows in the upper teens to mid 20s. && .DISCUSSION /Through Tuesday/... Issued at 227 PM MDT Tue Apr 14 2026 Water vapor satellite imagery shows the upper level trough tracking east across Utah. The trough will continue tracking eastward through tonight. Numerous showers and isolated thunderstorms will continueahead of the trough. Rain and snow showers will taper off this evening over the higher terrain and along the Front Range as the trough shifts over northeast Colorado. The snow level will be between 7,000 and 8,000 feet MSL. An additional 2 to 6 inches of snow is expected in the mountains. The rain showers will linger through the night over the northeast plains. Locally, up to half an inch of rainfall is possible over the northeast plains under the deformation zone. Cool northwest flow aloft will prevail Wednesday behind the exiting trough. High temperatures will reach the mid 60s to lower 70s across northeast Colorado. Flow aloft backs to the southwest Thursday ahead of the next storm system. This will bring warmer temperatures and continued dry conditions. South to southwest winds will increase as flow aloft increases and a surface low forms over Wyoming/northeast Colorado. The strongest winds, with gusts up to 40 mph, are expected over the mountains. Over the plains, the stronger winds will be found south of I-70. An upper level trough will track across the Central Rockies on Friday. Models are in good agreement that this trough will bring widespread light precipitation (less than half an inch) and cold temperatures. There are slight differences between the models regarding strength and timing, which could nudge amounts up or down. Precipitation may begin as rain across the plains, but theairmass quickly cools with snow expected Friday afternoon. Temperatures at 700mb fall to -8 to -12C, which is plenty cold enough for snow. As previouslydiscussed, precipitation amounts are generally expected to be light with snowfall amounts less than 3 inches across the plains. In addition to the needed precipitation, this system will be very cold. Overnight lows are expected to fall into the lower to mid 20s. Low lying areas will likely see colder temperatures, with readings in the 15 to 20 degree range. Saturday morning temperatures will be the coldest since mid March. Above-ground irrigation lines may be damaged Friday night and Saturday morning due to the hard freeze. It`s best (safest) to disconnect hoses and drain aboveground irrigation lines aheadof time. The upper level trough shifts east of the region by Saturday morning, leaving a dry northwest flow aloft in its wake. After Saturday morning`s cold start, temperatures climbed into the 50s across northeast Colorado. A little below average for this timeof year. Sunday through Tuesday, upper level ridging builds over the Central Rockies for Sunday and possibly into Monday. Once the ridge shifts east of the region late Monday or Tuesday, southwest flow aloft will prevail. All three days are expected to be warm and dry. Sunday will be the coolest withhighs in the upper 60s to lower 70s. Slow warming continues early next week and by Tuesday highs over northeast Colorado are expected to reach the upper 70s to lower 80s. Windy conditionsare not expected under this pattern, but if they occur, they would raise fire weather concerns. && .AVIATION /00Z TAFS through 00Z Thursday/... Issued at 617 PM MDT Tue Apr 14 2026 Recent radar imagery shows light rain showers in the vicinity of KDEN and KAPA at this time, as well as WNW winds gusting to 25KT. We have extended the TEMPO for -SHRA until 03Z, given that it is still possible for brief ceiling lowerings (5000-6000ft) and gusty winds to occur with the ongoing shower activity. Ceilings will improve later tonight after rain showers and virga move out of the area, and winds will turn variable with some weak drainage winds possible in the early morning hours. Winds on Wednesday afternoon will stay W-NW at all three TAF sites. There is a slight chance (30%) for some periods of gusts in the 20-25KT range at KBJC late in the afternoon due to favorable conditions for downsloping winds, but we opted not to include gusts in the TAF at this time due to low confidence. && .BOU WATCHES/WARNINGS/ADVISORIES... Red Flag Warning until 8 PM MDT this evening for COZ247. && $$ DISCUSSION...12 AVIATION...AA