Area Forecast Discussion
Issued by NWS Denver/Boulder, CO

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000 FXUS65 KBOU 152126 AFDBOU Area Forecast Discussion National Weather Service Denver/Boulder CO 226 PM MST Fri Dec 15 2017 .SHORT TERM...
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(This evening through Saturday) Issued at 226 PM MST Fri Dec 15 2017 Winds will be lessening thought the afternoon and evening across the region. Only slight changes made to the temperature for tonight. Cold pools were left in the forecast due to clear skies expected tonight allowing for radiational cooling. A dry cold front is expected to move into northeast Colorado Saturday morning. Highs for Saturday were lowered slightly to account for the 10 to 15 degrees temperature drop behind the front. .LONG TERM...(Saturday night through Friday) Issued at 226 PM MST Fri Dec 15 2017 There is weak southwesterly flow aloft for the forecast area Saturday night and Sunday. The upper trough axis moves across the CWA Sunday evening, then northerly flow aloft moves in overnight into Monday. For Monday afternoon and night, northwesterly flow aloft is in place. There is weak upward synoptic scale energy for the forecast area Saturday night into Sunday morning, then downward energy is progged into Monday afternoon. After that there is benign forcing in place. The boundary layer winds are northeasterly Saturday night. A very weak pressure gradient and wind field is progged on Sunday. Sunday night through Monday night more normal diurnal wind patterns are in place. Looking at moisture, there is some progged to increase Saturday night in the upper levels and down at the lower levels of the plains and lower foothills. The NAM deepens this moisture over the plains on Sunday, the other models do not. What moisture there is decreases somewhat Sunday night. All the models show some shallow alpine moisture Monday and Monday night. Concerning pops, will keep the thinking of the previous forecaster. The moisture is very shallow Saturday night into Sunday morning and perhaps we will see another minor freezing drizzle event for the western half of the plains. Will need some minor pops in the high mountains Sunday afternoon through Monday night. For temperatures, Sunday`s highs are 2-5 C cooler than Saturday`s. Monday`s highs are 4-8 C warmer than Sunday`s. For the later days, Tuesday through Friday, there will be flat upper ridging over the CWA Tuesday and Wednesday. There is strong southwesterly flow aloft Wednesday night and Thursday. An upper trough moves into the CWA late Thursday and hangs around over us through Friday well into next weekend. Models show limited measurable precipitation on the QPF fields Thursday and Thursday night. It does not look significant at this time. A fairly strong cold front moves across the CWA Wednesday night. Thursday night/Friday morning`s temperatures may be the coldest so far of this mild winter, but again, nothing significant.
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&& .AVIATION...
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(For the 18Z TAFS through 18Z Saturday afternoon) Issued at 226 PM MST Fri Dec 15 2017 VFR conditions through Saturday. Wind gusts to 25kts are expected at KBJC through 4Z. As the front moves in Saturday morning, winds are expected to switch to northeast around 16-18Z.
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&& .BOU WATCHES/WARNINGS/ADVISORIES... None. && $$ SHORT TERM...Sullivan LONG TERM....RJK AVIATION.....Sullivan

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