181
FXUS65 KGJT 241112
AFDGJT

Area Forecast Discussion
National Weather Service Grand Junction CO
512 AM MDT Fri May 24 2024

.KEY MESSAGES...

- Chances for showers and storms increase later today and
  continue through tomorrow. Gusty winds will be possible with
  these showers and storms.

- Mountain snow is possible generally above 9 kft with the
  impacts to the roads occurring tonight and tomorrow night.
  Highest chances and amounts will be in the northern and
  central mountains.

- Temperatures will run below normal through the weekend then
  increase next week. Precipitation chances remain low through
  mid week.

&&

.SHORT TERM /THROUGH SATURDAY/...
Issued at 139 AM MDT Fri May 24 2024

A trough will drop into the Great Basin later today allowing for
southwest flow aloft over our region. Modest moisture will advect
into the area in the form of clouds and eventually showers beginning
this afternoon. The low levels are rather dry and so initially
showers will have trouble reaching the ground. Winds are not
expected to be as high as yesterday in general, but any virga
could enhance gusts. The better moisture will spread over the
northern half of the forecast so that is where the chances are
for showers. Precip chances and coverage increase tonight as the
trough approaches from the west, again mainly north of I-70.
High temps today will range from 10 degrees below average up
north to near normal down south. Tomorrow, the base of the
trough passes over the area with the focus for lift across the
north. This will be the best timeframe for precip. Showers may
expand south of I-70 during the afternoon due to the trough
progressing eastward. It appears that minor QPF is possible in
the San Juans with none along the New Mexico state line. There
are indications that mountain snow is possible with this
system. The northern mountains may end up with several inches
generally above 9-10 kft. Instability will be present in the
prefrontal airmass tomorrow so expect thunderstorms. Winds
increase in general due to a tighter pressure gradient. Any
strong convection will have the chance to produce gusty winds
perhaps upwards of 50 mph. High temperatures will end up similar
to today.

&&

.LONG TERM /SATURDAY NIGHT THROUGH THURSDAY/...
Issued at 139 AM MDT Fri May 24 2024

The upper level trough will be just about directly over the CWA
Saturday night with models placing the heaviest precip along the
surface cold front. This band of precip looks to set up from
the northern mountains down through the Flat Tops to near
Douglas Pass in the Book Cliffs. As the night progresses, the
front will continue to drop south and east bringing some
rain/snow to the central mountains by late evening, the same for
the San Juans by midnight. This is a quick moving system and by
daybreak Sunday morning, the trough will be over the Front
Range with all precip having ended. When all is said done, 2 to
4 inches of snow above 10K feet will be the end result with 0.2
to 0.4 inches of QPF...some locally higher amounts expected for
both snow and rain. Previous model runs showed a second system
moving through on Sunday but all guidance is now indicating
stronger ridging building into the Intermountain West which will
keep that second system much further north. We`ll see mostly
sunny skies out west with partly cloudy skies along the Divide
and higher terrain, lifting through the day.

Ridging builds in Monday onwards and ushers in warmer temperatures
with some of the warmest temperatures seen so far this year for
Wednesday and Thursday. Under the ridging, we`ll see the usual
afternoon breezes and partly cloudy skies. Slight chance for some
convection firing along the Divide each afternoon but coverage and
chances are low (10 to 30%). A more pronounced trough passes through
Wednesday evening but with limited moisture, not expecting much, if
any, sensible weather. Wouldn`t be surprised if this changes as we
get closer to the event. Time will tell.

&&

.AVIATION /12Z TAFS THROUGH 12Z SATURDAY/...
Issued at 509 AM MDT Fri May 24 2024

VFR conditions have returned and will stay that way for the next
24 hours. Clouds up north will start to increase this afternoon
onwards ahead of the next system with scattered to broken skies
expected though ceilings will remain above 10K feet. Afternoon
breezes will reach 20 to 25 mph at times.

&&

.GJT WATCHES/WARNINGS/ADVISORIES...

CO...None.
UT...None.

&&

$$

SHORT TERM...KJS
LONG TERM...TGR
AVIATION...TGJT