Area Forecast Discussion
Issued by NWS Grand Junction, CO

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FXUS65 KGJT 231423

Area Forecast Discussion
National Weather Service GRAND JUNCTION CO
823 AM MDT Sun Apr 23 2017

Issued at 823 AM MDT Sun Apr 23 2017

Added Colorado Fire Weather Zone 292, the North Fork forecast area
which includes Delta and Montrose districts, to the Red Flag
Warning for this afternoon and evening as latest guidance supports
this. Relative humidity values will drop into the teens and
sufficient mixing will occur leading to warmer temperatures and
gusty winds above 25 mph.


.SHORT TERM...(Today through Monday)
Issued at 426 AM MDT Sun Apr 23 2017

The current infrared satellite image is showing some high clouds
moving into the area this morning ahead of an approaching cold
front. This cold front is currently located roughly along the
Nevada Utah border. Southerly winds will increase this afternoon
ahead of the front ushering in warm air advection which will help
the Grand Valley reach the mid 70s to lower 80s this afternoon. As
temperatures rise relative humidity will decrease into the teens
for low elevation areas in the CWA.

Showers and isolated thunderstorms will work their way into
northern portions of the CWA this evening as the cold front slides
across northern Utah and Colorado. Cool air will fill in from the
northwest behind the departing cold front on Monday resulting in
about 10 degrees of cooling for most areas, initiating a cooling
trend that will be felt all week long.

.LONG TERM...(Monday night through Saturday)
Issued at 426 AM MDT Sun Apr 23 2017

The current satellite water vapor image is showing a low pressure
system centered over southern Missouri and a ridge of high
pressure centered over the Four Corners with a cold front
approaching Utah. The 0000Z ECMWF and 0600Z GFS20 have initialized
well with these synoptic scale weather features and remain in good
agreement through at least Saturday.

Both of these forecast models depict unsettled weather across the
forecast area through nearly the entire upcoming week. This
unsettled weather will be driven by a vigorous jet stream which
will meander over Utah and Colorado all week long, steering
several weather disturbances through the intermountain west. These
disturbances will result in periods of showers and isolated
thunderstorms and eventually mountain snows as cold air lowers the
snow levels. The most notable of these disturbances will arrive
Thursday night as a fairly significant low pressure system begins
to slide across the forecast area. This low pressure system will
influence the weather through at least Saturday.


.AVIATION...(For the 12Z TAFS through 12Z Monday morning)
Issued at 426 AM MDT Sun Apr 23 2017

Southwesterly winds will increase and become gusty today as a
cold front approaches the forecast area. VFR conditions are
expected through at least early evening with increasing cloud
cover as the day progresses. Precipitation will become a
possibility this evening at terminals north of I-70.


Issued at 823 AM MDT Sun Apr 23 2017

Warm dry conditions remain on track for today with afternoon
temperatures expected to reach the upper 70s to low 80s in the
lower valleys of west-central and southwest Colorado as well as
southeast Utah today. Relative humidity values will fall into the
teens as southwesterly winds increase ahead of an approaching
cold front.

These warm dry atmospheric conditions combined with dry fuels in
western Colorado will lead to critical fire weather conditions.
Therefore, a Red Flag Warning is in effect this afternoon for
Fire Weather Zones 203, 207, 290 and 292 in central and southern
portions of western Colorado where fuels are being reported as
dry. For more detailed information please see the Red Flag Warning
on our web page; or see DENRFWGJT.

An active weather pattern also remains on track for the fire
district as a vigorous jet stream meanders over Utah and Colorado
steering several weather disturbances across the area this week.
Beginning on Monday, these weather disturbances will help to
lower temperatures and increase relative humidity values around
the district. The active weather pattern will stick around all


CO...Red Flag Warning from 1 PM this afternoon to 8 PM MDT this
     evening for COZ203-207-290-292.



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