Area Forecast Discussion
Issued by NWS Denver/Boulder, CO

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FXUS65 KBOU 140342

Area Forecast Discussion
National Weather Service Denver/Boulder CO
942 PM MDT Sun Aug 13 2017

Issued at 937 PM MDT Sun Aug 13 2017

Still a few weak showers upstream of the mountains and in the
just into the Nebraska panhandle, but they are all weakening and
not much threat east of the mountains any more. Only significant
change to the forecast was to keep cloud cover around much of the


.SHORT TERM...(This evening through Monday)
Issued at 333 PM MDT Sun Aug 13 2017

Scattered showers and thunderstorms are moving out of the
foothills and onto the adjacent plains, as expected. Shower
activity extends back into northwest Colorado, so more storms can
be expected for a couple more hours. Gusty winds, brief rain and
small hail will be the main threats. Gusts into the 40 to 50 mph
range should be expected. Clouds and showers will diminish as
sunset approaches. Further east, LAPS CAPE fields show only modest
instability (around 1000 j/kg). Stronger instability is present
over the far east parts of Colorado, so severe weather is expected
with the thunderstorms through the evening. The strongest storms
should develop over southwest Nebraska and western Kansas.

For Monday, it looks like another setup similar to today. Mostly
sunny morning skies will give way to increasing clouds and another
round of thunderstorms moving out of the mountains. Model
soundings only show about 1000 j/kg of CAPE, so storms should
remain below severe limits. Temperatures will continue running at
or just below seasonal normals.

.LONG TERM...(Monday night through Sunday)
Issued at 333 PM MDT Sun Aug 13 2017

Monday night, the upper level ridge axis will be over the Central
Plains an upper level trough axis stretching from southwest MT
into ncntrl NV. As a result the flow aloft will be west to
southwesterly. Subtropical moisture continue over the region with
NAM12 soundings still around one inch. Forecast soundings over
1000 j/kg for Denver, with higher values over 2000 j/kg over the
northeast plains. The pattern will remain unsettled through the
middle of the week as the upper trough shifts eastward and its
axis brushes the state Tuesday night into Wednesday, then another
secondary system may possibly follow suit on Thursday. Weak surge
from the north may also help to reinforce the low level moisture
across the northeast plains of CO.  By the end of the week the
ridge will be centered south and east of CO with a weak
southwesterly flow over the state. Confidence still low this far
out but trend for warmer and a little drier may kick in by that
time. Overall trend with the temperatures will continue through
the period with highs each day running slightly below normal.


.AVIATION...(For the 06Z TAFS through 06Z Monday night)
Issued at 937 PM MDT Sun Aug 13 2017

VFR through Monday. Isolated thunderstorms are expected after 21z
with a slight chance of variable winds gusting to 30 knots.




SHORT TERM...Dankers
LONG TERM...Cooper
AVIATION...Gimmestad is the U.S. government's official web portal to all federal, state and local government web resources and services.