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Area forecast discussion 
National Weather Service Denver/Boulder Colorado
149 PM MDT sun Jul 5 2015

Short term...(this afternoon through monday)
issued at 1139 am MDT sun Jul 5 2015

Lightning is exploding in the moisture plume from Arizona to
Wyoming. This is due to the lift associated with an upper trough
in northwest Colorado and a moist and marginally unstable airmass.
We still expect thunderstorms to continue to develop over the high
country and spread east this afternoon. As the upper trough slides
east...there are indications that we will have some subsidence and
downsloping behind the trough. As a result have lowered probability of precipitation along
the urban corridor for several hours tonight...while keeping
likely probability of precipitation in the northeast plains. Forecast convective available potential energy a little over
a 1000 may result in a severe thunderstorm in the far
northeast...otherwise thunderstorms late afternoon and evening
will be capable of wind gusts to 45 miles per hour and locall heavy rain...
but expected storm motion will limit the threat of flash flooding.

A cold front will spread south from Wyoming this evening...with
gradual moistening later tonight. Models showed the development of
stratus...but did not agree with much else for Monday. Bcconsall
looked reasonable for temperatures...for probability of precipitation on Monday it looks
as though the plains will be capped...but with upslope areas from
the Front Range to the Continental Divide getting scattered to
likely rain in the form of showers and a few thunderstorms in the
morning and thunderstorms in the afternoon. Expect low clouds
early...but cloudy most of the day with rising ceilings.

Long term...(monday night through saturday)
issued at 1139 am MDT sun Jul 5 2015

Monsoonal pattern starts to come together to bring increased
moisture into the region for next week.

On Monday night into Tuesday the upper level pattern remains zonal
with the closed low continuing to progress northward along the
Pacific coast. NE flow upslope will increase along the foothills
and Palmer Divide that will keep a chance of showers into the
evening for the plains. Thunderstorm activity will stay isolated
over the higher terrain but could result in periods of heavy rain
as precipitable waters remain above 1 inch. For Tuesday the upper level flow
starts to switch to a more SW direction that will aid in
continuing to bring moisture north into Colorado. Surface flow
will be from the southeast. Thunderstorms will develop over the mountains
during the afternoon with showers over the plains. The far
NE plains should remain relatively stable with showers closer to
the foothills. Highs on Tuesday will remain cooler than normal
only getting into the upper 70s and lower 80s.

For the latter half of the week the ridge over the Great Basin
amplifies as the low over the Pacific pushes inland. Upper level
flow remains west-southwest with steady moisture flow from the south. This
will keep a slight chance of afternoon shower and thunderstorm
development for the region. Temperatures will steadily increase
through the week into the upper 80s to lower 90s by Sunday as the
ridge continues to build.


Aviation...(for the tafs through 18z Monday morning)
issued at 1139 am MDT sun Jul 5 2015

East winds will give way to west or northwest winds as the upper
trough moves east this evening. The cold front will advance south
this evening with northerly winds developing before midnight.
Expect low MVFR conditions to become widespread in the pre dawn
hours...and not getting back to VFR ceilings until Monday
afternoon. Scattered thunderstorms can be expected this afternoon
and evening with gusts to 45 miles per hour possible with outflow winds.
Later tonight with the low ceilings scattered showers will also


Bou watches/warnings/advisories...


Short term...rtg
long term...Bowen

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