Area Forecast Discussion
Issued by NWS Denver/Boulder, CO

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FXUS65 KBOU 252049

Area Forecast Discussion
National Weather Service Denver/Boulder CO
249 PM MDT MON JUL 25 2016

.SHORT TERM...(This afternoon through Tuesday)
Issued at 249 PM MDT Mon Jul 25 2016

Upper level ridge centered near the four corner will drift west
the next 24 hours. This will cause flow aloft to turn from west to
northwest on Tuesday. Precipitable water values are up to a
quarter inch drier today. This will help favor gusty outflow winds
as the main threat with the storms. Best chance for storms will be
south of I-70 where moisture will be a little better. On the
eastern plains where CAPE and shear is better, can`t rule out a
severe thunderstorm or two with large hail and winds to 70 mph.

For Tuesday, a weak wave embedded in the flow aloft along with
slightly more moisture will bring a better chance for
thunderstorms. Heavy rain and gusty outflow winds will be the main
threat with the storms. A severe storm or two will be possible
over far eastern Colorado where the best shear and instability
will reside. Temperatures will be slightly warmer with highs
climbing above 90 degrees over much of northeast Colorado.

.LONG TERM...(Tuesday night through Sunday)
Issued at 249 PM MDT Mon Jul 25 2016

An upper trough and surface front passing southeast across the
area Tuesday night will help push scattered thunderstorms east
into Kansas through midnight, with gusty outflow winds, small
hail and brief moderate to heavy rainfall the main impacts. A
stronger storm may be possible with strong winds and large hail
east of a line from Sterling to Akron. Cooler air behind the
trough and clearing skies will allow for minimum temperatures to
cool a degree or two cooler than tonight`s readings.

The upper ridge will build over the southeastern Great Basin
Wednesday and remain there through the rest of the week putting
northwest flow aloft over Colorado. This will push subtropical
moisture southeast and thereby decreasing the chances for storms
over the high terrain to a slight chance. Shortwaves in the flow
aloft coming out of Canada will send a couple fronts into the
northeastern Colorado plains, though different models have
different solutions for the timing and extent. Overall, expect
some cooling over the northeastern corner of the state with an
increase in moisture as it wraps in from the Great Plains. The
cold frontal boundary will provide a focus for isolated to
scattered storms to form each afternoon and evening over the
northeastern plains, with a slight chance for strong to severe
storms near the NE/KS state borders. The forecast area further
west will have little to no chance of showers...although this may
depend on how far west the frontal boundary moves west.
Temperatures Thursday and Friday will be back in the mid to upper
80s for the plains.

The upper ridge will begin pushing east across the state on
Saturday then develop southwesterly flow aloft for Sunday and
Monday as a trough drops into the Pacific Northwest. This will
allow for warming temperatures and a return of subtropical
moisture. Look for increasing chances for storms in the mountains
with a slight chance over the plains.


.AVIATION...(For the 18Z TAFS through 18Z Tuesday afternoon)
Issued at 249 PM MDT Mon Jul 25 2016

There will be a slight chance for thunderstorms at the Denver
airports through 03z. Gusty outflow winds to 40 knots and brief
heavy rain will be the main threats from the storms. Outflow winds
from the thunderstorms may produce a wind shift or two through
03z. Southerly winds will prevail overnight and Tuesday morning.
There will be a better chance for thunderstorms Tuesday
afternoon...after 21z.


.BOU Watches/Warnings/Advisories...


LONG TERM...Kriederman
AVIATION...Meier is the U.S. government's official web portal to all federal, state and local government web resources and services.