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Area forecast discussion
National Weather Service Denver/Boulder Colorado
259 PM MDT Mon Sep 16 2019

Short term...(this evening through tuesday)
issued at 258 PM MDT Mon Sep 16 2019

Water vapor satellite shows a trough departing northeast Colorado
and moving into Nebraska with dry air in place over our County Warning Area.
There will be weak showers and storms over the mountains as well
as along a convergence zone from Monument Hill to Yuma. High LCLs
and dry sub-cloud air will result in most precipitation
evaporating before it reaches the surface. These showers will end
early tonight with low temperatures around 10 degrees above

Water vapor satellite also shows a strong trough over northern
California and northwestern Nevada. This trough will continue to
move east-northeastward and will center itself over Wyoming during
midday tomorrow. Models indicate qg descent on the back side of
this trough over our County Warning Area during the afternoon hours. In addition,
there isn't any cooling aloft over our County Warning Area tomorrow compared to
today with a weak dry inversion around 500 mb during the
afternoon. Because of this, storms will struggle to form along a
cold front that moves through during the afternoon. The best
instability will be in the mountains as scattered storms are
expected there. Mainly dry conditions are expected over the
plains with only a couple storms near the northern border of

The subsident flow will aid in developing strong winds tomorrow.
The high terrain will have gusts above 40 mph with the mountain
peaks seeing gusts up to 60 mph. Winds over the plains will be a
bit more sporadic but will gust up to 35 mph especially behind the
cold front. Otherwise, highs will continue to be well above

Long term...(tuesday night through monday)
issued at 258 PM MDT Mon Sep 16 2019

We will remain under the influence of southwesterly to southerly
flow aloft through Friday as two sequential upper level troughs
set up to the north of Colorado. Because of the warmer and drier
southwest flow loft, temperatures will remain 5 to 10 degree
warmer than seasonal normals, which are in the upper 70s, with
Denver forecast to see 80s through the Friday.

Tuesday evening, model soundings over the plains indicate potential
for gusty winds with convection associated with an inverted v
profile. Storms are expected to move from west to east.

With drier air in place, moisture will be meager through the work
week with precipitable water topping out near 0.7 - 0.8 inches over
the plains. There will be a series of Lee side surface lows setting
up in each day. A chance of afternoon and evening storms is expected
over the high country, while the plains see a slight chance of
convection. Thursday evening the GFS and European models show an
increase in qg Omega with a deep upper level low approaching.

Temperatures will remain 5 to 10 degree warmer than seasonal
normals, which are in the upper 70s, with Denver being forecast to
see 80s through the Friday. Saturday and Sunday temperature
guidance is trending closer to seasonal normals with highs in the
upper 70s. This is due to the change to northwest flow aloft on
the backside of the trough.


Aviation...(for the 18z tafs through 18z Tuesday afternoon)
issued at 258 PM MDT Mon Sep 16 2019

VFR conditions are expected through Tuesday morning. Winds will
be light and variable throughout the afternoon at den. Showers to
the west and south of den may produce outflow boundaries late
this afternoon or early evening. Normal drainage patterns will
overtake tonight.


Bou watches/warnings/advisories...


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