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fxus65 kgjt 162350 

Area forecast discussion
National Weather Service Grand Junction Colorado
550 PM MDT Mon Sep 16 2019

Short term...(tonight through Tuesday night)
issued at 111 PM MDT Mon Sep 16 2019

Relatively moist southwest flow aloft with precipitable water
values 0.60-0.90 inches and weak cape this afternoon and evening
will support orographically driven scattered convection the
remainder of the day. Steering flow aloft is strong enough to
move showers/thunderstorms to the northeast over adjacent
valleys. As usual, with the dry low levels, gusty outflow winds 40
to 50 mph will occur around the thunderstorms. A deeper trough
over the West Coast will move east tonight and Tuesday, but lift
to the north of Colorado. A glancing blow of mid and upper level
dynamics and a stalling surface frontal boundary may affect the
northern areas with a bit more organization to
showers/thunderstorms Tuesday. Otherwise, expect another round of
orographically driven convection Tuesday, with a decrease in
activity late in the day as drier air moves in behind the upper
level trough axis passage.

Long term...(wednesday through monday)
issued at 111 PM MDT Mon Sep 16 2019

Dry southwest flow aloft Wednesday along with a tightening
pressure gradient over Utah will likely yield afternoon gusty
winds, which combined with low relative humidity may result in
marginal critical fire weather conditions over eastern Utah. Will
keep an eye on that for possible fire weather highlights. A
relatively deep upper level trough will move east from the West
Coast Thursday with associated trough axis and stronger surface
front moving through on Friday. Thursday afternoon into early
Friday looks like the next period of highest chance and greatest
coverage of showers and thunderstorms. The snow level may drop
Friday to near 9000 ft over northeast UT, to near
10,000 ft park and Gore ranges, to around 11,000 feet on the San
Juans. So, we could see some light accumulations on the higher
peaks. Temperatures will be coolest Friday, then rise slowly
through next weekend, but remain slightly below normal under a
progressive and wavy northwest flow pattern.


Aviation...(for the 00z tafs through 00z Tuesday evening)
issued at 541 PM MDT Mon Sep 16 2019

Isolated/scattered shower and thunderstorm activity will continue
into the early evening hours. Expect thunderstorms in the vicinity and brief reduction in
ceilings and visibility in stronger storms. VFR conditions should largely
prevail for all taf sites with ceilings staying above ils breakpoints.
Shower activity will diminish by late this evening. Gusty
southwest winds will develop by 18z on Tuesday, with gusts
exceeding 30 knots at some taf sites.


Gjt watches/warnings/advisories...


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