Area Forecast Discussion
Issued by NWS Denver/Boulder, CO

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000 FXUS65 KBOU 210207 AFDBOU Area Forecast Discussion National Weather Service Denver/Boulder CO 807 PM MDT Fri Oct 20 2017 .UPDATE...
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Issued at 754 PM MDT Fri Oct 20 2017 Pcpn was increasing across wrn CO and will gradually move into the mtns as mid lvl qg ascent associated with the upper level trough moves across overnight. Snow amounts over the higher mtns will range fm 2 to 6 inches. Across the plains, a band of showers may dvlp by 09z closer to the WY border and then move quickly across the far nern plains by 14z as a cdfnt moves across. Behind the fnt gusty NWLY winds will occur with a few gusts fm 40 to 50 mph for a few hours especially closer to the WY border.
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&& .SHORT TERM...(This evening through Saturday) Issued at 340 PM MDT Fri Oct 20 2017 This evening a 700 mb front will move through bringing very strong cold air advection. Late today into tonight, the higher mountains are forecast to reach 45 kts, especially across the northern mountains and Wyoming border. Lows tonight will drop into the 40s on the plains and will be near 20-30 F over the mountains. Highs Saturday will remain cooler, only expected to reach 50-60 on the plains and 30-40 across the higher terrain. Near the Wyoming border the gusts could return to around 40 kts. Snow accumulation of 2 to 5 inches is expected Friday night into Saturday morning above 8500 feet. At this point, we don`t feel the need for any highlights. .LONG TERM...(Saturday night through Friday) Issued at 340 PM MDT Fri Oct 20 2017 Strong northwest flow overnight and a surface lee trough will result in strong downsloping winds over the foothills. While the rest of the plains will likely hit freezing or below, areas in and along the foothills will remain warmer. Gusts of 40 to 50 mph will be common, especially in the wind prone areas. Northwest flow will continue Sunday through Wednesday bringing dry weather to the area. After a warm up on Sunday, a shortwave trough sinking down over the Great Plains and Great Lakes will push in cooler air. Wednesday will warm up again as the next system drops down out of western Canada. Latest models have all trended much deeper and colder with the expected system on Thursday. GFS, the Canadian and EC now will have snow levels down over the plains with the quick moving system. With it being in Day 7 and having the potential for more differences in the models due to effects from Typhoon Lam that gets caught up in the flow next week, have lowered the temperatures for Thursday and Friday, but will keep it still warm enough for rain over the plains during the day Thursday then down to snow. The moisture will push south Friday for a dry day but colder air will likely still linger. && .AVIATION...
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(For the 00Z TAFS through 00Z Saturday evening) Issued at 754 PM MDT Fri Oct 20 2017 Winds have switched back to SSW early this evening. Overnight latest data has winds becoming more NW around midnight and then N or NE by 09Z lasting thru 12Z Sat. This is somewhat different than what was shown earlier, so overall confidence is not high for winds directions and speeds late tonight. On Sat gusty NWLY winds should gradually dvlp after 15Z.
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&& .BOU WATCHES/WARNINGS/ADVISORIES... None. && $$ UPDATE...RPK SHORT TERM...Sullivan LONG TERM...Kriederman AVIATION...RPK

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