Area Forecast Discussion
Issued by NWS Denver/Boulder, CO

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FXUS65 KBOU 010926

Area Forecast Discussion
National Weather Service Denver/Boulder CO
326 AM MDT FRI JUL 1 2016

.SHORT TERM...(Today and tonight)
Issued at 324 AM MDT Fri Jul 1 2016

Confidence in today`s fcst is not high based on what happened
yesterday.  Currently there appears to be a disturbance moving
across nrn CO which is triggering some sct showers across the
plains.  Meanwhile a 2nd feature is supposed to move into the four
corners area late this aftn and then move across srn CO tonight.
Precipitable water values by aftn will range fm near 1.20" along the
front range to as high as 1.50" across the ern plains.  At the
surface the flow east of the mtns will become more sely this aftn
with potentially a Denver Cyclone developing by midday to the sw of

Overall with abundant moisture should see another round of showers
and tstms across the higher terrain this aftn into the early evening
hours with the best focus possibly along and south of I-70. Over
nern CO if a Denver Cyclone does dvlp like the HRRR shows then a
convergence zone may center itself over the Denver metro area which
could act as a focus for stronger tstm development by early aftn and
across the Palmer Divide.  Further north would expect tstm coverage
will be more sct.  With high PW`s the potential exists for heavy
rainfall in some areas especially fm Denver south to the Palmer
Divide and points eastward.  The big quesion is whether storms will
gradually propagate to the east along outflow boundaries or will
they potentially train over the same areas.  At this point not sure
how things will evolve so will not issue a Flash Flood Watch at this
time due to so much uncertainty.  As for svr threat mid lvl temps
rise a few degrees by aftn so believe main threat would be gusty
winds especially across the Palmer Divide towards Limon where mid
lvl winds will be stronger.  As for highs this aftn will keep
readings mainly in the 70s across the plains.

For tonight if the disturbance over swrn CO does move across srn CO
then threat of additional showers and tstms may continue overnight
especially across srn areas of the cwa.

.LONG TERM...(Saturday through Thursday)
Issued at 224 AM MDT Fri Jul 1 2016

On Saturday, an upper level ridge of high pressure will be centered
over the Gulf of Mexico, with a shortwave trough moving across
Colorado. This pattern should produce scattered afternoon and
evening showers and storms across the region. Pw`s are around an
inch, therefore some of the storms could produce brief heavy rain.

On Sunday, the models show the upper high rebuilding over the Desert
Southwest which should bring drier air into the state. This would
result in warmer and drier weather across north central and
northeastern Colorado. There may be enough moisture, combined with
daytime heating, to produce isolated to scattered high based storms
mainly over the higher terrain.

On Monday, the models show a 50kt jet max moving across southern
Colorado, while the ECMWF has a weak shortwave moving across the
state. These features may be enough to produce a few storms across
the CWA. Soundings look somewhat dry, therefore would expect
mainly light to moderate rain and gusty winds with the storms.

Tuesday looks to be the driest day of the week as GFS and ECMWF
soundings show PW`s falling below 0.75 inch.

On Wednesday, the models show the flow of monsoonal moisture
returning to the region as the upper level ridge shifts eastward
into the southern plains states. If this pattern verifies, we should
see an increase in shower and thunderstorms activity across north
central and northeastern Colorado Wednesday and Thursday.

As for Temperatures, Saturday should be the coolest day of the
period with highs in the 70s and low 80s on the plains. Temperatures
should warm back into the 80s on Sunday and into the 90s by


.AVIATION...(For the 06Z TAFS through 06Z Friday night)
Issued at 224 AM MDT Fri Jul 1 2016

HRRR and RAP continue to show some type of Denver Cyclone by midday
with a convergence zone setting up over Denver.  Thus could see
stronger storms dvlp along this bndry as early as 19z. Both models
show some potential of redevelopment by 23z after first line of
storms move through by 21z.  Thus will have a tempo/prob group thru
at least 00z.  For tonight there may be a chc of showers and
possibly an early evening tstm with activity decreasing by 03z.

As for winds will keep them mainly sse thru early aftn however
outflow boundaries will likely lead to chaotic wind directions for
most of the aftn after 19z.  For this evening will have winds
becoming ssw.


Issued at 324 AM MDT Fri Jul 1 2016

Storms will have the potential to drop 1 to 2 inches of rain in
one hour with isolated amounts up to 3 inches in a few spots. The
most likely area for heavier rainfall would be from Denver south
to the Palmer Divide extending eastward towards Limon. In addition
areas in the southern Foothills could see some heavier rainfall as


.BOU Watches/Warnings/Advisories...


LONG TERM...Kalina
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