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984
FXUS65 KGJT 171802
AFDGJT

Area Forecast Discussion
National Weather Service Grand Junction CO
1202 PM MDT Mon Jun 17 2024

.KEY MESSAGES...

- Hot, dry, windy conditions continue today with winds gusting
  35-45 mph across the region. Red Flag Warnings remain in place
  for southeast UT and portions of western CO.

- A cold front this evening will work from the northwest into
  the remainder of the CWA by Tuesday morning. Afternoon highs
  will be nearly 10 degrees below normal to normal on Tuesday,
  then warm some on Wednesday.

- Unsettled conditions return Thursday with afternoon showers
  and thunderstorms expected into the weekend. Exceptional PWAT
  values are expected to produce some heavier rain later this
  week.

&&

.SHORT TERM /THROUGH TUESDAY/...
Issued at 401 AM MDT Mon Jun 17 2024

A robust jet max is digging into the Great Basin this morning,
carving out a frontal boundary that makes its way into the CWA this
evening. Beforehand though, we will see another day of hot, dry,
windy conditions around the region. Red Flag Warnings remain in
place for southeast UT and western CO. The Grand Junction evening
sounding paints a clear picture of the dry boundary layer conditions
and the neatly stacked southwesterly flow aloft. A few clouds can be
seen on satellite streaming off the Wasatch to our west, but this is
about as close to moisture as we will get today, as the southern tip
of the cold front drags through the CWA with nary a drop of rain to
be spared. Winds will pick up this morning and hang on through the
evening with gusts 35-45 mph across the region, with the strongest
winds favoring our northern counties, where proximity to the jet max
overhead and well mixed conditions align this afternoon. Frontal
passage will enter northeast UT around 5 pm MDT and push
southeastward through the evening hours. Surface winds will remain
strong behind the front until we can clear the strong winds aloft,
which won`t happen until the early morning hours of Tuesday.
Thankfully relative humidities will recover pretty quickly along the
front and we will start to see Red Flag conditions diminish in the
late evening hours. With the winds aloft washing out late tonight as
the upper trough drags through, our Red Flag zones will see winds
quickly diminish. Afternoon highs will push well into the 90s again
for our low valleys and deserts. A few clouds in the northern
portions of the CWA will help a little along the front, but too
little too late thanks to the strong warm air advection across the
region. Tuesday highs will get a nice adjustment downward,
especially in our northern counties where the cooler air doesn`t
have to fight past the Tavaputs. Highs will range from near normal
to 10 degrees below climatology Tuesday afternoon. Winds will pick
up again Tuesday afternoon, but remain below concern for critical
fire weather conditions.

&&

.LONG TERM /TUESDAY NIGHT THROUGH SUNDAY/...
Issued at 401 AM MDT Mon Jun 17 2024

A dry, southwesterly flow dominates the synoptic pattern mid week
with an upper-level trough staying put over the western CONUS.
Temperatures moderate some Wednesday and again on Thursday as 500mb
heights gradually rise. Most will stay dry under sunny skies on
Wednesday, but a few diurnal showers and storms cannot be ruled
out with the highest instability forecast along the eastern
edge of the forecast area.

Confidence is increasing for an anomalously strong plume of moisture
to wrap into the area Thursday PM into Friday, especially near the
Four Corners region. Precipitable water values are currently
projected to be upwards of 90% higher than normal for this time of
year across the forecast area and up to 99% higher than normal near
the Four Corners. The global models and their ensembles have also
latched onto this rich plume of moisture as each model run shows
stronger moisture advection resulting in periods of showers and
storms Thursday afternoon through Friday evening. While it is still
too early to pin down the potential impacts, this will certainly be
a period to watch very closely in the coming days. Shower and
thunderstorm activity will continue into the weekend with
coverage decreasing by Sunday afternoon, as moisture moves east
over the Divide.

&&

.AVIATION /18Z TAFS THROUGH 18Z TUESDAY/...
-- Changed Discussion --
Issued at 1202 PM MDT Mon Jun 17 2024

Gusty winds will occur this afternoon and evening with gusts in
the 30 to 40 kt range. Clear skies will give way to some SCT
cloud cover this evening and overnight as a dry cold front
moves through with CIGS remaining above ILS breakpoints. Gusty
winds should subside after midnight but could be occasionally
breezy at times through the night.
-- End Changed Discussion --

&&

.FIRE WEATHER...
Issued at 401 AM MDT Mon Jun 17 2024

Red Flag Warnings are in effect through this evening for
southeast UT and portions of western CO. Winds will gust 35-45
mph across the region this afternoon ahead of a cold front that
will work its way into the CWA this evening. Relative humidities
will recover late tonight and winds begin to subside by early
Tuesday morning.

&&

.GJT WATCHES/WARNINGS/ADVISORIES...

-- Changed Discussion --
CO...Red Flag Warning until 10 PM MDT this evening for COZ203-207-
     290>293.
UT...Red Flag Warning until 10 PM MDT this evening for UTZ490-491.
-- End Changed Discussion --

&&

$$

SHORT TERM...LTB
LONG TERM...KAA
AVIATION...MDA
FIRE WEATHER...TGJT