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Area forecast discussion 
National Weather Service Grand Junction Colorado
230 PM MDT Wednesday Oct 7 2015

Short term...(tonight through Thursday night)
issued at 230 PM MDT Wednesday Oct 7 2015

Showers will continue through the afternoon from the Abajo
Mountains NE to about Independence Pass. Most of the thunderstorm
activity will be over the San Juans and valleys just to the west.
Increased instability this afternoon is the main driver with any
weak upper support diminishing through the late afternoon. Showers
will diminish towards sunset with a few showers lingering beyond
sunset over the higher San Juans...then dry after midnight. The
southern zones will have a colder night...the north just a degree
or two warmer than last night.

Little change indicated in model forecasts for Thursday. Latest
output continued to ease the closed low southward...well into
the Mexican state of Sonora. Meanwhile...a shortwave trough moving
southeastward across the northern rockies is expected to brush the
northern Colorado mountains. Models divided on whether there will
be sufficient moisture to generate showers over the Elkhead and
park ranges so will continue with slight chance probability of precipitation Thursday
afternoon and evening. Dynamic forcing wanes in concert with
diurnal cooling so expecting dry conditions and clearing skies
Thursday night.

High temperatures Thursday will rise to a few degrees above normal
in response to ridging aloft. However...clearing skies with drier
conditions will allow for better radiational cooling and lows near
..or a bit below normal Thursday night.

Long term...(friday through wednesday)
issued at 230 PM MDT Wednesday Oct 7 2015

Most models indicated dry conditions will persist into Friday as
high pressure builds over the Great Basin. However...the nam80 was
the outlier and depicted another weak shortwave trough moving
through during the afternoon which could bring showers/thunderstorms tp
the San Juan Mountains. Have little confidence in this solution so
will leave out mention of moist convection over this area Friday

Beyond Friday models were consistent in keeping the forecast area
precipitation through the middle of the coming week. Ec and GFS
continued to track the low center over Mexico westward over the
eastern Pacific off the coast of the Baja California peninsula through the
middle of next week. Meanwhile...a weak shortwave moving through
the northern rockies will flatten the ridge over the area this
weekend...but will not bring any moisture to the area.
Consequently...expecting unseasonably mild and dry conditions to


Aviation...(for the 18z tafs through 18z Thursday noon)
issued at 1115 am MDT Wednesday Oct 7 2015

Most areas will see VFR conditions today except for the San Juans
and areas south as they remain the favored area for precipitation. Ktex
and kdro will likely see broken ceilings with vcsh/thunderstorms in the vicinity for the afternoon
hours. Other taf sites will see some clouds but do not anticipate
any significant aviation concerns. Conditions will improve across
the forecast area after 02z. Clouds clear the San Juan Mountains by 06z
with VFR conditions expected through Thursday morning.


Gjt watches/warnings/advisories...




Short term...Joe/nl
long layers

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