367
FXUS65 KPSR 232036
AFDPSR
Area Forecast Discussion
National Weather Service Phoenix AZ
136 PM MST Fri Jan 23 2026
.KEY MESSAGES...
- An unsettled weather pattern will carry us through Saturday,
with temperatures cooling near to slightly below normal this
weekend and chances for a few rounds of showers across South
Central and Eastern Arizona.
- Some convective showers capable of producing small hail and
lightning will be possible Saturday afternoon into the evening.
- Dry conditions return on Sunday, with temperatures gradually
warming next week.
&&
.SHORT TERM /TODAY THROUGH SATURDAY/...
Water vapor imagery show the closed low diving down the Northern
Baja Coast moving southeastwards and is expected to traverse just
south of the state through Northern Mexico over the next couple
of days. The position of the low has already began to advect
moisture in to our region with Thursday`s 03Z radiosonde launch
showing PWATS already at 0.6" up from 0.41" from the 00Z launch.
Model guidance suggest PWATs climbing to a peak of 0.75-0.9" by
this evening into Saturday across much of South Central AZ and to
the east in the higher terrain areas. With moisture already in
place with more to come as the low progresses, this afternoon can
expect to see spotty virga to light showers across much of the
east valley and east of the Metro.
By Saturday the closed low will begin its journey eastwards
across Northern Mexico. As mentioned above PWATs will continue to
increase as the system moves, with the NAEFS mean values peaking
around the 90th percentile of CFSR climatology across the forecast
area and even exceeding the 98th percentile in the southeastern
corner of AZ later today. However, GFS bufr soundings project the
moisture to be mostly contained in the midlevels, generally above
600 mb. In conjunction with the low passing to our south another
disturbance will be diving south along the Interior West passing
along Northern AZ. This will help facilitate showers to become
more widespread across the eastern CWA Saturday. This disturbance
has lead HREF mean MUCAPE values to be between 100-250 J/kg
across S.Central AZ in the afternoon, expanding eastwards by the
late evening hours. This is enough to produce convective activity
resulting in the possibility of small hail and lightning in the
affected areas, most notably in the evening and bleeding into the
overnight hours as vorticity peaks during this time, providing
extra fuel for shower activity to occur.
This second disturbance will also be responsible for temperatures
cooling to near normal today and below normal starting Saturday.
Today`s afternoon highs will be in the low to mid 70s across the
lower deserts with some areas in the Phoenix Metro seeing highs
just under 70 degrees. Saturday can expect morning lows in the
low to mid 50s in the Phoenix Metro, and in the mid to high 40s
in the western portions of our CWA, and in the higher terrain
areas. Afternoon highs tomorrow will be in the mid to high 60s in
central AZ, and in the low 70s out west.
&&
.LONG TERM /SUNDAY THROUGH THURSDAY/...
The poorly defined cold front that sweeps the area from the north
late Saturday into Sunday will usher in a cooler and much drier
air mass, ending precipitation chances by early Sunday morning.
Temperatures will drop noticeably from Saturday to Sunday, from
near normal into a 2-5 degree below normal range. Morning lows are
forecast to range from the mid 30s to mid 40s starting Sunday,
with some of the typically colder rural, low-lying areas
potentially flirting with freezing temperatures (32F or less) into
early next week. NBM probabilities for freezing temperatures peak
Sunday night/Monday morning around 20-50% in those rural and
sheltered river valley locations, except slightly higher (50-80%)
in the Tonto Basin.
Ensembles remain in excellent agreement that ridging off the West
Coast will slide eastward and build over the Western US during
the first half of next week, promoting a gradual warming trend.
However, WPC cluster analysis reveals discrepancies on how strong
the ridge will become, and whether any disturbances will undercut
or weaken the ridge during the latter half of next week.
Regardless, after the unsettled weather Friday-Saturday, expect
quiet, dry weather to return Sunday and persist through at least
the middle of next week.
&&
.AVIATION...Updated at 1846Z.
South Central Arizona including KPHX, KIWA, KSDL, and KDVT:
Lowered CIGs, rounds of VCSH/SHRA, shifting winds, and isolated
TS will be the primary aviation impacts and forecast challenges
through Saturday. There is currently a break in shower activity,
but showers will return by this afternoon/evening. Winds through
this afternoon will favor a SE-S component with speeds around
5-10 kt. CIGs prior to the next round of showers will stay up
around 10K ft AGL. With the next round of shower activity winds
will be light (aob 5 kt) and favor a E component with some
variability and CIGs will lower down to around 6-7K ft AGL. CIGs
will be lowest Saturday morning, likely after midnight, down to
around 4-6K ft AGL with odds of staying above 4K ft at 80%. A
break in shower activity is likely again later Saturday morning
through early to mid afternoon. Toward late afternoon another
round of scattered showers are expected and this round will have
the potential for an isolated thunderstorm with gusty winds and
small hail. Winds turn W-NW Saturday afternoon with sustained
speeds up to 8-13 kt. CIGs in the afternoon will be around 5-7K ft
AGL
Southeast California/Southwest Arizona including KIPL and KBLH:
No aviation weather concerns will exist through the current TAF
period under periods of thick mid/high level cloud decks. Winds
will favor a southerly component during the day at KBLH and shift
from SW to SE at KIPL by this afternoon. Expect speeds to remain
light, generally aob 6 kts at both terminals with extended periods
of nearly calm conditions amongst typical diurnal wind shifts.
&&
.FIRE WEATHER...
Unsettled weather will carry us through Saturday, with
temperatures cooling near to slightly below normal and chances for
a few rounds of showers across South-Central and Eastern AZ. The
best chances for wetting rains (up to 60-90%) will be focused
east and southeast of the Phoenix area, especially over the higher
terrain. MinRHs will increase from 20-40% areawide today to
30-50% Saturday, with even higher values over the higher terrain
of the eastern districts, then decreasing back to between 15-30%
on Sunday with a low to high gradient from west to east. A weak
cold front will sweep the area from the north late Saturday into
Sunday, increasing northerly winds especially in the western
districts along the Colorado River. As such, anticipate mostly
light winds (under 15 mph) through Saturday morning, followed by
locally breezy north winds Saturday afternoon into the evening,
and lingering breeziness on Sunday. &&
.PSR WATCHES/WARNINGS/ADVISORIES...
AZ...None.
CA...None.
&&
$$
SHORT TERM...Ryan/Whittock
LONG TERM...Whittock
AVIATION...Benedict
FIRE WEATHER...Ryan/Whittock
NWS Phoenix Office
Tucson, AZ 
