Area Forecast Discussion
Issued by NWS Grand Junction, CO

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FXUS65 KGJT 241015

Area Forecast Discussion
National Weather Service GRAND JUNCTION CO
415 AM MDT Wed May 24 2017

.SHORT TERM...(Today through Thursday)
Issued at 301 AM MDT Wed May 24 2017

Another dry day is in store for the forecast area with significant
warming anticipated. Full sun will allow temps to make a quick
run upward this morning with developing southwest flow as we await
the arrival of a strong cold front that will sweep through
tonight and Thursday. Temperatures this afternoon will make a run
toward the warmest so far this season with some 90s expected
across southeast Utah. Winds pick up a bit this afternoon with
deep mixing anticipated, but stronger gusts expected on Thursday,
especially along and ahead of the southward moving front.

Cloud cover increases tonight with scattered showers developing
through the late evening hours, generally north of Interstate 70.
This activity will work south late tonight and Thursday before
stalling along and north of the San Juan mountains in southwest
Colorado. With the front stalling in this area, expect very dry
conditions to persist over our Four Corners valleys with
increasing winds as we look for another day of deep mixing. This
drives consistent and somewhat persistent winds down to the
surface on Thursday. When combined with dry fuels and low humidity
values, concerns for fire weather conditions will be elevated.
More details on this can be found below in the fire weather

After a very warm Wednesday, expect temps to be a solid 10 to 15
degrees cooler on Thursday for areas north of the front, or near
seasonal normals. Very warm conditions persist south of the front
through Thursday afternoon.

.LONG TERM...(Thursday night through Tuesday)
Issued at 301 AM MDT Wed May 24 2017

Flat zonal flow will be in place Thursday night with showers
lingering over the area. Flow backs to more southwesterly on
Friday as we see another re-enforcing shot of cooler air slide
south across Idaho and Wyoming, dropping into our forecast area
by Friday. This will keep cool and unsettled weather in place
through the weekend with final push of cooler air sliding through
on Saturday. Models continue to advertise the strong west coast
ridge to slide east across the rockies, but have backed of on it`s
arrival once again. As a result, expect the somewhat active
pattern across our area to continue into early next week, although
showers are expected to be more confined to the afternoon and
evening hours, versus the potential nocturnal activity early on in
this extended. Next interesting factor will be the arrival of
another low that will undercut the western ridge by Wednesday.
Moisture sweeps northward across New Mexico up into the Four
Corners are by midweek. The pattern looks wet at this point,
especially south of the San Juans and into New Mexico. Still
several days away, but early signs pointing to an uptick in
precipitation as the week wears on. Temperatures will be dancing
around the normal mark for much of the extended period.


.AVIATION...(For the 12Z TAFS through 12Z Thursday morning)
Issued at 301 AM MDT Wed May 24 2017

VFR conditions will continue through early this evening. A cold
front is expected to move south and approach northeast Utah and
northwest Colorado overnight. The front will make steady progress
southward, before stalling along the San Juan Mountains in
southwest Colorado. Gusty winds can be expected along and near
higher mountains with speeds up to 35 kts. Clouds increase
overnight with ILS CIGS moving across the northern zones and
scattered showers and thunderstorms developing after 03z this
evening. The unsettled weather will continue through Thursday with
local MVFR CIGS anticipated near showers. Mountains will also be
obscured at times tonight and Thursday near showers.


Issued at 301 AM MDT Wed May 24 2017

A cold front will be moving south across western Colorado tonight
and Thursday. The front is expected to stall north of the San Juan
Mountains, with scattered showers developing along and north of
the front. Across the southern valleys, especially across
Colorado Fire Weather Zone 207, gusty southwest to west winds are
expected Thursday afternoon and evening. With the front stalled to
the north, expect temperatures to remain above normal with
relative humidity values dropping below 15 percent for several
hours. With winds in place, low humidities and critical fuels,
per our land agency partners, will be upgrading the fire weather
watch to a red flag warning from early Thursday afternoon through
the early evening hours. North of the San Juans, scattered to
numerous showers are expected with a cooler air mass in place.


CO...Red Flag Warning from noon to 7 PM MDT Thursday for COZ207.



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