Area Forecast Discussion
Issued by NWS Grand Junction, CO

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FXUS65 KGJT 262228

Area Forecast Discussion
National Weather Service Grand Junction CO
428 PM MDT Sat May 26 2018

.SHORT TERM...(Tonight through Sunday night)
Issued at 146 PM MDT Sat May 26 2018

Gusty southwesterly winds have developed this afternoon as
anticipated in response to the presence of a 60-70 knot jetstreak
aloft. These strong surface winds have allowed temperatures to
climb to well above seasonal norms with cities like Moab, Grand
Junction, and Delta sitting on the verge of 90 degrees as of 1
PM. Single digit relative humidity values are widespread this
afternoon under a fairly cloudless sky, though some high cirrus
clouds are currently streaming across the east-central portion of
our forecast area. Needless to say, having said thus much, the
Red Flag Warnings will remain in effect for southeast-east central
Utah and much of western Colorado through 10 PM this evening as
planned. Even though it is a holiday weekend, outdoor burning is
strongly discouraged given that new fire starts may be difficult
or impossible to control under these strong winds. As always,
please check with the local authorities on any ongoing fire
restrictions in your area.

Winds will gradually taper off with the loss of daytime heating
after sunset and as the stronger winds aloft skirt to the
southeast. However, 250 mb winds will still remain between 50-60
knots overnight and through Sunday afternoon, resulting in
periodically breezy conditions. The area of low pressure sitting
over the Great Basin will slowly begin to lift to the northeast
on Sunday. This marginal shift in its position may allow for some
isolated showers to move across the northern mountains during the
afternoon hours and continuing into Monday. This will also allow
for the ridge of high pressure to relocate further east into the
Plains which will bring some relief to our area temperature wise
as temperatures finally cool back down to near seasonal levels.

.LONG TERM...(Monday through Saturday)
Issued at 146 PM MDT Sat May 26 2018

The low will transition to an open wave on Monday as it lifts to
the northeast, resulting in a slight uptick in moisture across
northeastern Utah and northwestern Colorado. The higher elevations
north of I-70 have the best chance to receive scattered
convection on Monday and into Tuesday with some showers
potentially firing off further south as the upper level trough
heads for the Dakotas. Elsewhere, expect an increase in mid and
high level clouds with cooler temperatures. This relief from the
summer-like heat will be short-lived, however, as upper level flow
once again turns to the southwest as the next Pacific trough digs
into the western CONUS on Wednesday. Mild southwest flow will
persist across eastern Utah and western Colorado through the end
of the work week. An ejected shortwave trough, or potentially a
cutoff low, will dive into the Great Basin on Friday before
progressing through our forecast area on Saturday. The arrival of
this system into the southwestern CONUS could result in a return
to critical fire weather conditions by Thursday so that will
definitely be something to monitor over the coming days.


.AVIATION...(For the 00Z TAFS through 00Z Sunday evening)
Issued at 426 PM MDT Sat May 26 2018

Strong southwest winds at the surface and aloft will cause
widespread mechanical turbulence of the entire area. Otherwise,
VFR conditions will CIGS well above ILS breakpoints will prevail
for the next 24 hours at all TAF sites.


Issued at 146 PM MDT Sat May 26 2018

Widespread critical fire weather conditions will continue across
western CO and SE/E-Central UT into the evening hours with strong
winds aloft mixing down to the surface under a 60-70 knot upper
level jet, low relative humidities, near record high temperatures,
and dry vegetation.

As mentioned above, surface winds should begin to decouple from
the winds aloft around sunset this evening and significantly
decrease by late evening. Periodic breezy conditions will
redevelop Sunday as 50 knot winds persist aloft, but a weaker
pressure gradient should keep surface winds below Red Flag


CO...Red Flag Warning until 10 PM MDT this evening for COZ200-202-203-

UT...Red Flag Warning until 10 PM MDT this evening for UTZ490-491.



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