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Area forecast discussion 
National Weather Service Denver/Boulder Colorado
430 am MDT Monday Jul 6 2015

Short term...(today through tonight )
issued at 425 am MDT Monday Jul 6 2015

A moist and marginally unstable airmass now in place over
northeast Colorado will remain little changed today...and
temperatures today will be much cooler with the anticipated
abundant cloud cover...and weak cold air advection surface and aloft.
Models show the upper ridge over the region past few days
weakens in response to a weak shortwave moving through the
northern stream north of Colorado. Outflow from large convective
complex over the northern Great Plains early last evening partly
responsible for the moist northeasterly/upslope flow east off the mountains at
this time. Models show this flow lingering throughout the day
which continues to pile moist air up against the Front Range.
Present precipitable water values along the Front Range in the
1.25 to 1.35 inch range this hour. See little change in these
numbers today. However...areas farther out on the plains are
likely to see drier air filtering down from northern areas next
24 hours. Precipitation probabilities in the 30 to 40 percent range still
appears reasonable for today on the plains. Severe weather chances
look quite low today except for the northestern corner of the state
where greater sunshine and instability could result in a few near
severe storms after 2 PM today.

For the high country...subtropical moisture spreading northward
along The Spine of The Rockies is prognosticated to reach southwest
sections of the forecast area by early this afternoon. Difficult
to Pin Point any forcing mechanisms embedded in this flow. So
storm formation over the mountains and high valleys will largely be the
product of daytime heating and orographics. However will need to
keep an eye on storms over southern sections of Park County as the wind
and stability profile could favor a brief severe T-storm or two
later this afternoon.

Tonight...specific humidity/boundary layer Theta-E levels are
forecast to remain little changed except on the far northestern plains
where drier air continues to flow down from the north. Should see
precipitation chances falling off through the evening hours with
cooling...expect perhaps over and along the southern foothills and eastern
sections of Park County where isolated storms could linger well
beyond midnight. Low temperatures tonight should little different
from those the night before.



Long term...(tuesday through sunday)
issued at 425 am MDT Monday Jul 6 2015

On Tuesday...temperatures will moderate a little but remain well
below normal across the urban corridor and adjacent plains. The
flow aloft will be westerly with a ridge to the south...a closed
low off the central California coast...and a tough across the northern
U.S. Subtropical moisture will keep the precipitable water values high over the
mountains where the best instability will be. Will keep likely probability of precipitation
in the high country. There will be a better chance of
thunderstorms over the northeast plains with convective available potential energy in the 500-1000
j/kg range. Southeasterly winds across eastern Colorado could help to initiate a
Denver cyclone in the afternoon. Tuesday night...nocturnal showers
with a slight chance of thunderstorms could persist overnight...especially
in the high country. On Wednesday...the ridge will build a bit
over Colorado as the closed low off the California coast moves inland. The
surface high over the plains will continue it shift with an inverted
surface trough over eastern Colorado. Temperatures will warm a bit more but
still well below normal. Overall will go with chance probability of precipitation for most of
the County Warning Area. The warming trend will continue through the rest of the
week with the flow aloft southwesterly on Thursday and Friday with
a broad ridge over the southeastern U.S. Subtropical moisture will
continue to advect into Colorado from the south...so chance in the
mountains...slight chance plains in the late afternoon/evening time frame. Over
the weekend...ridge over the southeastern U.S will retrograde to the west
and start to build. Temperatures will continue to warm as moisture
from the south will get pinched off so probability of precipitation will be more isolated at
that time.

&&

Aviation...(for the tafs through 12z Tuesday morning)
issued at 425 am MDT Monday Jul 6 2015

Ils conditions with low ceilings the main concern next 4-7 hours
at Denver area terminals. Could see ceilings lowering below 1000 feet
above ground level around 12z for a couple of hours before gradually lifting
through the morning. Not much in the way of precipitation in the
area at the present time. However later this morning could see
scattered light rain showers drifting off the Front Range. Then by
afternoon with further heating...isolated to scattered
thunderstorms. Much cooler temperatures today should reduce the
risk of both heavy rainfall and severe weather in the metropolitan area.
But can rule out entirely. Looking for partial clearing overnight
and most of the shower activity in the metropolitan area ending by around
midnight.

&&

Bou watches/warnings/advisories...
none.
&&

$$

Short term...Baker
long term...Cooper
aviation...Baker

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