669
FXUS65 KFGZ 261558
AFDFGZ

Area Forecast Discussion
National Weather Service Flagstaff AZ
858 AM MST Wed Jun 26 2024

.SYNOPSIS...Daily chances for afternoon and evening showers and
thunderstorms will continue through Thursday. Activity then slowly
decreases and becomes more focused over eastern Arizona by the
weekend.

&&

.UPDATE...A well developed MCV rotated through northern
Arizona overnight continuing to bring areas of light to moderate
rainfall. It can still be seen rotating just northeast of
Flagstaff this morning. Overall, we expect less activity today
than yesterday given the abundant cloud cover across north-central
and northeastern Arizona, as well as likely subsidence behind the
MCV. The FGZ sounding this morning indicated a couple degrees of
warming aloft, meaning less instability. Nonetheless, there is
still a juicy air mass in place, and areas that see some clearing
will see convection develop. We expect the greatest instability
today to be generally south of the Mogollon Rim and perhaps
western Coconino county, where the best clearing is. This is also
in line with where the CAMs project the best instability. Have
updated precipitation chances today to decrease across the
northeast and keep better chances south/west of the Rim. Heavy
rain and flash flooding will continue to be the main concern,
especially give yesterday`s rainfall. Small and gusty winds will
also be possible in the stronger cells.

&&

.PREV DISCUSSION /355 AM MST/...Today...The resulting MCV from
Tuesday`s storms remains over much of northern Arizona, and
should gradually lift northward into far north-central Arizona as
it decays. Thus, cloud cover will remain over a large portion of
the area for the overnight and into the early morning hours.

Convective initiation later in the morning and into the afternoon
will largely be dependent on where there is less cloud cover
destabilization can occur. 00Z HREF guidance has the greatest
insatiability concentrated mainly south of I-40 for the first
part of the day, then gradually increasing over eastern Arizona
as cloud cover begins to break. Given the still abnormal abundance
of moisture, flash flooding will continue to be a threat this
afternoon. A slight increase in storm motions (around 5-15 kts)
will lower the threat a bit, but is largely a nominal decrease in
the risk. HREF PMM guidance has the greatest threat for flash
flooding mainly along the Mogollon Rim and into eastern Arizona
near the New Mexico border.

Thursday...A weak through brushes past Arizona on Thursday, drier
more westerly flow aloft begins to set in across western Arizona.
Remaining moisture over the eastern-half of the state will allow
for isolated to scattered showers and thunderstorms to develop,
especially over the Four Corners region.

With the influence of the trough, storm motions look to increase
to around 15-25 kts, thereby reducing the residency time of any
one storm. Thus, the flash flood threat looks to be a bit lower,
however any areas that see training thunderstorms or rain
sensitive areas could see flash flooding. 0-6 km wind shear also
looks to increase to around 20-30 kts over northern and eastern
Arizona. The shear combined with around 1000 J/Kg of surface CAPE
may lead to a increased severe threat. Thus, any stronger storm
will have the potential to produce strong gusty winds and hail.

Friday through Tuesday...Much drier air sets in by Friday, with the
vast majority of the area remaining rain free. The only exception
may be near the White Mountains where a few isolated showers will
be possible during the afternoon.

As the trough lifts, high pressure gradually builds back into the
southwest. Moisture slowly makes a return, with chances for
showers and thunderstorms increasing each day from southeast to
northwest.

Outside of the preciptation, temperatures look to remain near-normal
through the period. Winds may be a tad on the breezier side, with
peak afternoon gusts around 20-25 mph.

&&

.AVIATION...Wednesday 26/12Z through Thursday 27/12Z...
Predominately VFR conditions across the region early this
morning, excluding a small cluster of storms that are approaching
KSEZ from the south. Assuming this cluster sustains itself, it`ll
arrive to KFLG in the next couple hours but shouldn`t persist very
long. Elsewhere high based -SHRA stretches from KCMR to east of
KPGA. That shower activity will continue to diminish. Widely
scattered TS will once again develop across the region after 18Z
and persist until after 00Z. Heavier TS will produce isolated
areas of sub VFR ceilings and visibilities.

OUTLOOK...Thursday 27/12Z through Saturday 29/12Z...Expect mostly
VFR conditions, excluding sub VFR conditions under afternoon TS
that will once again develop Thursday afternoon. Drier weather
returns Friday. Gusty/erratic winds possible near storm
development, with SW winds 10-20 kts expected otherwise.

&&

.FIRE WEATHER...Today and Thursday...Afternoon showers and
thunderstorms continue. Stronger storms will bring heavy rainfall,
hail, lightning, and gusty, erratic winds. On Thursday, the emphasis
shifts primarily to the Mogollon Rim northeast and eastward. Winds
on Wednesday will mainly be driven by outflows. By Thursday, expect
southwest winds 10 to 15 mph, gusts from 20 to 30 mph, especially
for the central and western zones.

Friday through Sunday...Most of the central and western zones become
drier, warmer and breezy. Afternoon storm chances continue for the
eastern zones, but coverage becomes more isolated. Expect southwest
winds 10 to 15 mph, gusts from 20 to 30 mph, each day.

&&

.FGZ WATCHES/WARNINGS/ADVISORIES...None.

&&

$$

PUBLIC...MCT/Humphreys
AVIATION...RKR
FIRE WEATHER...RKR

For Northern Arizona weather information visit
weather.gov/flagstaff