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FXUS65 KBOU 232246

Area Forecast Discussion
National Weather Service Denver/Boulder CO
346 PM MST Thu Nov 23 2017

.SHORT TERM...(This evening through Friday)
Issued at 133 PM MST Thu Nov 23 2017

A shortwave will bring stronger flow aloft with some increase in
the mountain winds and wave clouds overnight, then a cold front
and a little cooling aloft and mid level moisture by midday
Friday. The moisture layer should be pretty shallow, so the
forecast of scattered light showers still looks appropriate. Could
be an inch or two accumulation in some spots. Temperatures should
still be mild ahead of the front with highs slightly cooler than
today ahead of the front. Expecting temperatures on the plains to
drop into the 50s in the afternoon behind the front. All of this
is well covered in the current forecast.

.LONG TERM...(Friday night through Thursday)
Issued at 345 PM MST Thu Nov 23 2017

Models have a jet maximum of northwesterly flow aloft over the 
CWA Friday night into Saturday afternoon. The flow aloft decreases
Saturday night as an upper ridge moves into Colorado. The ridge 
axis is over the eastern border of Colorado late Sunday afternoon,
with the flow aloft become southwesterly Sunday night. There is 
benign synoptic scale energy on the GS Omega fields Friday night 
through Sunday night. For moisture, there is some in the upper 
level mainly here and there Friday overnight through Sunday night.
The QPF fields show a tad of measurable precipitation over the 
high mountains early Friday evening, then nothing through Sunday 
night. Will keep some minor pops there. For temperatures, 
Saturday's highs will be 2-5 C colder than Friday's highs. 
Sunday's highs are 4-7 C warmer than Saturday's. For the later 
day's Monday through Thursday, models have strong southwesterly 
flow aloft Monday. There is an upper trough with closed 
circulation at it's base near the four corners Tuesday at 12Z. 
This weakens and pushes eastward into southwesterly Kansas by 12Z 
Wednesday morning. There is upper ridging over the state 
Wednesday, then another upper trough into Thursday, while the GFS 
and Canadian have another upper trough move across Colorado on 
Thursday. The medium range models are not in good sync, timing- 
wise, with this system. Pops seem reasonable later Monday into
Tuesday, especially in the mountains. 


.AVIATION...(For the 18Z TAFS through 18Z Friday afternoon)
Issued at 133 PM MST Thu Nov 23 2017

VFR through Friday. Winds will go southerly at KDEN/KAPA around
00z-02z with west winds gusting to around 20 knots at KBJC
overnight. A cold front will bring a shift to north winds around
18z Friday, with gusts of 20-30 knots for a few hours behind the



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