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Area forecast discussion 
National Weather Service Denver/Boulder Colorado
813 PM MDT Monday Jul 6 2015

Update...
issued at 807 PM MDT Monday Jul 6 2015

Some very light rain/drizzle continues in and near the foothills as
weak upslope flow continues. Precipitation has ended in the mountains however
additional activity over western Colorado may eventually affect portions of
the mountains overnight.

&&

Short term...(this evening through tuesday)
issued at 337 PM MDT Monday Jul 6 2015

Increased moisture will remain in place over the region with
continued cloudy and rain for NE Colorado through the remainder of
the day. Thick stratus has prevented heating of the lower atmosphere so
convection on the plains will be hard to initiate. However...over
Park County there is a slight chance of development later this
afternoon and into the early evening. Marginal cape values could
help to fire off some thunderstorms into the evening. Shear is low
so severe is not expected. Main threats will be gusty winds and
brief heavy rain as precipitable water values are still above 1 inch. Rain showers
will move closer to the foothills this evening with gradual
clearing over the NE Colorado late this evening into the early
hours on Tuesday. Lows tonight will dip into the lower 50s for the
plains and lower 40s for the mountains.

For Tuesday early morning some light fog and stratus development
will be possible over the plains...especially the far NE corner
with some light clearing overnight. Lower ceilings will remain
over the foothills and mountains with lingering rain showers over
the higher terrain. An upper level disturbance embedded in the SW
flow aloft will increase chances for afternoon thunderstorm
development over the mountains and Park County. After the
disturbance moves through southeast flow could aid in Denver cyclone
development late tomorrow afternoon. With increased heating
combined with possible convergence south-southwest of Denver maintained a
slight chance of thunderstorms for the foothills and Western
Plains.

Long term...(tuesday night through monday)
issued at 337 PM MDT Monday Jul 6 2015

A return to a wetter regime seems to be in the offing as the flow
of sub-tropical moisture from the Gulf of Mexico has returned to
the state. Over the next several days the 700 mb specific humidity
fields from all the models show a heathy fetch of subtropical
moisture across northern Mexico...Arizona...New Mexico and
Colorado. At the same time...the upper level ridge will be setting
up over the southeastern U.S. For a couple days. Low level
circulations across eastern Colorado will be upslope...helping to
hold moisture against the foothills. The airmass is going to be
warming and Delaware-stabilizing through the week with afternoon showers
and thunderstorms expected each day. Locally heavy rainfall will
become a threat each afternoon from possibly slow moving storms.

At the end of the week and over the weekend...the upper high is
going to retrograde and establish itself over Colorado and the
Great Basin. This is going warm temperatures up and also diminish
the inflow of Gulf moisture at middle and upper levels. Low level
moisture advection may continue as a thermal low developing over
the Great Basin will induce southeasterly flow across eastern
Colorado. Warming temperatures aloft may be enough to cap the
airmass each afternoon...leading to a decrease in shower coverage.
It may also allow for the storms which do break the cap to produce
very heavy rain as winds will be weak at all levels and storm
motions will be very low. Will have a few periods in the latter
half of the forecast that are free of precipitation across the
forecast area...but that may change with time.

In the end the typical forecast of afternoon and evening
thunderstorms with temperatures around seasonal normals is what we
will go with.

&&

Aviation...(for the tafs through 06z Tuesday evening)
issued at 807 PM MDT Monday Jul 6 2015

Ceilings have begun to rise however smoke from fires up in Canada
has worked its way into the area with surface visibilities in the 3-5
mile range. Not sure how long these lower visibilities will last
but will raise them above 6 miles by 04z.

&&

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

$$

Update...rpk
short term...Bowen
long term...dankers
aviation...Bowen

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