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Area forecast discussion 
National Weather Service Grand Junction Colorado
412 am MDT Sat Jul 26 2014

Short term...(today through sunday)
issued at 412 am MDT Sat Jul 26 2014

Monsoon moisture continued to stream over the area early this
morning as high pressure now centered over west-central New
Mexico. A weak shortwave trough over northeast Utah and northwest
Colorado was responsible for sustaining lingering showers over
The Flat Tops and portions of the Roan Plateau. A few of these
showers may linger past sunrise so added some isolated probability of precipitation to
those areas.

00z/kgjt sounding contained 0.9 inches precipitable water...which
is down by about a tenth from yesterday but still considerable.
Dewpoints were relatively homogeneous across the forecast area
with readings in the upper 40s and low 50s. Given moisture levels to say that stage is set for another round of afternoon
thunderstorms developing over the higher terrain. As diurnal
circulations break down some storms will move from the higher
terrain and over the valleys. Less cape available for today/S
storms according to bufr soundings though slow moving storms will
be capable of high precipitation rates and localized flooding or
debris/mud flows.

As is common this time of year...afternoon highs largely dependent
on timing and location of thunderstorm development but overall
expect highs near or just a bit below seasonal norms.

Shower activity will diminish during the evening hours on Saturday.
Scattered shower and thunderstorm activity will re-develop by late
Sunday morning over the higher terrain and spread over the
remainder of the forecast area during the afternoon hours. Models
are slowly increasing moisture on expect another round
of scattered showers and thunderstorms with the strongest storms
producing heavy rain...gusty winds and frequent lightning.

Long term...(sunday night through friday)
issued at 412 am MDT Sat Jul 26 2014

Partial clearing is expected Sunday night with a slight chance of
shower/thunderstorm activity extending into the late-night hours.
The monsoonal moisture surge will increase on Monday and will be
enhanced by a wave rotating around the flow. Have continued the
trend of higher probability of precipitation with heavy rain possible and the potential
for flooding with the stronger storms developing during the

Models hinting at an easterly wave wrapping into the area Tuesday
impinging on an airmass containing precipitable water values in
excess of 1 inch. Stands to reason that there is the potential for
widespread thunderstorm activity with areas of very heavy rain.
Models indicated the remainder of the week favors the usual
diurnal shower and thunderstorm activity favoring the mountains.

Temperatures expected to be cooler than normal Tuesday due to
increased clouds and showers/thunderstorms. During the remainder
of the week look for temperatures to hover near normal.


Aviation...(for the 12z tafs through 12z Sunday morning)
issued at 412 am MDT Sat Jul 26 2014

Expect VFR conditions to continue through midday. Thereafter...
daytime heating will generate another round of scattered showers
and thunderstorms over the mountains which will drift over
adjacent valleys during the latter part of the afternoon and into
the evening. Monsoon moisture is rather deep so storms moving over
taf sites will bring brief periods of IFR visibility and possibly MVFR
ceilings in heavy rain. Activity is expected to diminish overnight.


Gjt watches/warnings/advisories...




long term...mpm/nl layers

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