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fxus65 kgjt 191716 

Area forecast discussion
National Weather Service Grand Junction Colorado
1116 am MDT Fri Jul 19 2019

Short term...(today through saturday)
issued at 240 am MDT Fri Jul 19 2019

Precipitable water values will continue to bottom out today before
moisture gradually increases over the next 24 to 36 hours. West-
southwest flow aloft will slowly shift to the southwest this
afternoon as lower heights remain situated across the Pacific
northwest and as the subtropical high is situated to the east. The
tighter gradient will persist through this evening allowing for
critical fire weather conditions to redevelop across portions of
northwest Colorado where a red flag warning remains in effect.
Elsewhere, expect another dry and warm day with occasional breezy
conditions. Increased moisture, primarily in the form of mid and
high level clouds, will move across the south with high res models
showing an isolated shower or two developing over the San Juans
this afternoon.

Late tonight and into Saturday will see the flow aloft transition
to more of a south-southwesterly pattern as the lower heights
over the Pacific northwest retreat offshore and as the high
amplifies northward. Moisture will continue to gradually trickle
into the region with mostly clear to partly cloudy skies tonight
and isolated to scattered showers and thunderstorms over the
Continental Divide by Saturday afternoon as an embedded shortwave
helps fuel convection. Forecast soundings across the south keep
the lower levels of the atmosphere dry so gusty outflow winds will
be the primary threat with storms.

Long term...(saturday night through thursday)
issued at 240 am MDT Fri Jul 19 2019

The high will continue to remain in an unfavorable position for
eastern Utah and western Colorado to receive a direct tap of
subtropical moisture through the weekend. However, early next week
will see the center of the high drift further north with
subtropical moisture advecting into the region in the clockwise
flow. Still not a direct tap...but better than nothing! Showers
and thunderstorms that develop on Sunday and Monday will continue
to favor the higher terrain but, as additional moisture is
introduced, activity will increase in coverage and drift into the
valleys by Tuesday and into Wednesday. The GFS continues differ
from the Euro in regards to how much moisture is available,
especially going into the latter half of the work week. The
center of the high looks to progress to the southwest which would
inhibit any additional subtropical moisture from streaming into
the region. Regardless, any lingering moisture will continue to be
recycled each day resulting in scattered diurnal convection.
Additionally, expect temperatures to cool back down to near or at
seasonal normals in response to increased clouds and showers.


Aviation...(for the 18z tafs through 18z Saturday afternoon)
issued at 1113 am MDT Fri Jul 19 2019

Minimal aviation concerns today as some high clouds move overhead
this afternoon. Areas north will see some gusty winds of 20 to
25kts. VFR remains in place for the next 24 hours.


Fire weather...
issued at 240 am MDT Fri Jul 19 2019

Hot, dry and breezy conditions will persist this afternoon and
evening leading to critical fire weather conditions across
Colorado fire weather zone 200 where a red flag warning is in
effect. However, localized red flag conditions are possible
elsewhere. Critical fire weather conditions are not expected on
Saturday and continuing for the next several days as moisture
is slowly drawn northward by a shift in the weather pattern,
leading to an increase in clouds, showers and thunderstorms.


Gjt watches/warnings/advisories... flag warning until 8 PM MDT this evening for coz200.



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