Red Canyon, Utah Weather Forecast Discussion

240
FXUS65 KGJT 271732
AFDGJT
Area Forecast Discussion
National Weather Service Grand Junction CO
1132 AM MDT Sat Sep 27 2025
.KEY MESSAGES...
- Afternoon and evening convection continues each day through
  the weekend, possibly beyond. Sunday looks to be the most
  active day.
- Some storms may be capable of producing strong winds as well
  as heavy rainfall, which could impact the recent burn scars.
- Light snow can`t be ruled out for the highest elevations over
  the weekend though no impacts are expected to roadways.
&&
.SHORT TERM /THROUGH SUNDAY/...
Issued at 258 AM MDT Sat Sep 27 2025
H500 hand analysis and satellite imagery is showing the closed
low has migrated to the Baja region as anticipated while the
northern stream wave is moving through the Northern Plains.
Satellite derived PWAT suggests the SW cyclone is tapping into
the SubTropics and possibly even pulling in moisture associated
with Narda out in the EPac. The first spiral of this mositure
looks to lift across our southern border by mid morning just
slightly slower than thought yesterday. With the northern wave
out of the picture we should get a better push of this moisture
into the central CWA and precipitation chances reflect this
today. Water vapor is showing a dry slot behind this spiral of
mositure over central AZ this morning. Model dynamic trop and
mid level moisture fields show this feature lifting across the
4 Corners by mid afternoon on the nose of a jet emerging on the
downstream side of the low. The added ascent from these features
and some insolation should help tap into the moderate
instability and produce more organized convection. Heavy
rainfall rates...hail and gusty winds will all be threats across
the 4 Corners through the PM hours. Nocturnal convection is more
likely tonight with this strong moisture continuing to lift
northward along with any convectively forced mesoscale spins.
The SoCal low will begin to lift northward on Sunday as a
larger trough moves into the EPac. QG ascent increases ahead of
this over our CWA as a result and with well above normal
moisture in place it`s not hard to see why there will be a
fairly good chance of widespread shower and thunderstorm
activity. CAPE values in some of the CAMs are 700-1200 j/kg by
the afternoon but not sure all of that can be realized with the
amount of cloudiness in place. However there will be some
probability of stronger storms again over the southern and
western part of the CWA. Sunday has consistently been the apex
of this event and will have to watch several burn scars and
other areas for excessive runoff as well. Above normal
temperatures today drop back toward normal tomorrow.
&&
.LONG TERM /SUNDAY NIGHT THROUGH FRIDAY/...
Issued at 258 AM MDT Sat Sep 27 2025
Models have slowed down the arrival of the shortwave trough by about
12 hours the past fews runs, but despite that we are still expecting
scattered to widespread showers during day. This could result in
less forcing than previously anticipated. Another uncertainty is the
amount of cloud cover in the morning, which will dictate how much
instability can build for the afternoon convection. The more sun the
more storms. The strongest cells may be capable of small hail, gusty
winds and heavy rainfall. A few models do not bring the shortwave
overhead until Monday morning therefore showers could stick around
through out the day. Another shortwave trough could come in from the
west bringing the next chance for precipitation. As of the now the
timing is uncertain and overall it looks to be a quick wave. The
long term will be comprised of temperatures near normal to slightly
below normal due to the wave activity.
&&
.AVIATION /18Z TAFS THROUGH 18Z SUNDAY/...
Issued at 1126 AM MDT Sat Sep 27 2025
Mid to high level clouds have just about reached the I-70
corridor this afternoon with lower and denser clouds noted for
southern portions of the forecast area. Showers and
thunderstorms are expected to start firing shortly. This
convection will first affect KTEX and KDRO before shifting
northward later this afternoon and evening. Despite this
convection, VFR conditions will remain in place though some
brief MVFR can`t be ruled out under the stronger cells. Some
ILS breakpoints may also be reached as showers and lower
ceilings move through. Included PROB30 groups for these showers
and storms for many TAF sites. Unsettled weather will continue
through tomorrow.
&&
.GJT WATCHES/WARNINGS/ADVISORIES...
CO...None.
UT...None.
&&
$$
SHORT TERM...15
LONG TERM...KJS
AVIATION...TGJT

NWS GJT Office Area Forecast Discussion