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Area forecast discussion 
National Weather Service Grand Junction Colorado
538 PM MDT Friday Sep 4 2015

Short term...(tonight through Saturday night)
issued at 344 PM MDT Friday Sep 4 2015

An unsettled moist SW flow continues through these periods.

This afternoon-overnight...the morning model runs continue to not
resolve organized forcing. Jet support remains stretched SW-NE
across the forecast area and precipitation water values are near one inch
in the lower elevations. Storm motion is the NE at
25kts. The hrrr seems to be capturing the early afternoon shower
coverage with the NAM and GFS too wet for this evening. The hrrr
suggests the evening storms will be mainly near the Continental
Divide and perhaps the eastern uintas. Then isolated to scattered
showers linger over the south into Saturday morning.

If today is any indication of how tomorrow will be...then some showers
and thunderstorms are expected but nothing too impressive. Models
have been overdoing coverage and intensity last few days with both
NAM and GFS painting widespread precipitation which just hasn't
been panning out. Even with decent upper level support...there's
not been any real good surface trigger to get strong convection
going. For Saturday...GFS showing another day of widespread precipitation
while NAM has really pulled back. Forecast follows NAM so dropped
probability of precipitation good amount. That's not to say we won't see any precipitation...we
will...some afternoon/evening thunderstorms are expected with some
heavy rain under the stronger cells. Expect coverage will be
similar to today. Of course...having said that chance has now
increased for tomorrow to be very active day. Stay tuned. As far
as temperatures are concerned...plenty of cloud cover will keep temperatures
near normal to a few degrees below.

Long term...(sunday through friday)
issued at 344 PM MDT Friday Sep 4 2015

A few days of nice weather on tap as low pressure shifts north and
the assod trough forces the moisture stream to our east. A few
garden variety showers/storms may popup in the afternoon/evening
more so for Monday and Tuesday but they will be very few and far
between favoring the highest terrain. Most of the County Warning Area will see
plenty of sun with some cumulus buildup in the afternoon with scattered
skies being predominant.

The remainder of the long term will see pieces of energy rotating
around the periphery of high pressure to our south kicking off
some showers/storms mainly over the San Juans. Mean flow remains
from the west to northwest keeping temperatures seasonable for this time
of year.


Aviation...(for the 00z tafs through 00z Saturday evening)
issued at 538 PM MDT Friday Sep 4 2015

Moist southwest flow will keep isolated to scattered showers
popping over the eastern Great Basin to The Rockies overnight.
Radar trends show ktex...kase...kege have the best potential to be
impacted by gusty winds near the showers through 05/02z...otherwise
VFR continues. Some of these gusts will exceed 35 miles per hour through
late evening. In general things quiet down after midnight with a
return of the shower and thunderstorm activity tomorrow afternoon.


Gjt watches/warnings/advisories...


Short term...Joe/tgr
long term...tgr

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