Holtville, California 7 Day Weather Forecast

Wx Forecast - Wx Discussion - Wx Aviation

097
FXUS65 KPSR 302005
AFDPSR

Area Forecast Discussion
National Weather Service Phoenix AZ
105 PM MST Fri May 30 2025

.KEY MESSAGES...

- Near to above normal temperatures continue for Saturday with
  highs to 105 degrees across portions of the lower deserts.

- An influx of tropical moisture over the weekend will aid in
  widespread chances for showers and scattered thunderstorms,
  mainly Sunday into Sunday night.

- Below normal temperatures with highs in the nineties across the
lower deserts are expected from Sunday into the middle part of next
week before tempeatures rise above normal again by late next week.

&&

.DISCUSSION...
An anomalous pattern continues to take shape across the region as we
monitor an unusually wet pattern by late this weekend into early
next week along with below normal temperatures. Water vapor
imagery showing the feature of interest as a cut off low
off the northwest coast of Baja California, with an actual
southwest movement today. This low will combine with moisture
from Tropical Storm Alvin as it begins to drift north to help
pull near record moisture across the area for what is typically a
dry time of year.

The upper low will remain fairy stationary until Sunday when it
begins steering northeast toward the area. This will maintain
one more dry day Saturday and above normal temperatures with
highs nearing 105 in the lower deserts. With that said, the
continued south/southeast flow ahead of upper low will draw
moisture northwest from TS Alvin. The largest flux of moisture
into our region will occur as the low approaches Sunday and Sunday
night. Precipitable Water values reaching 300% of normal on
Sunday, with values upwards of 1.5 inches. The moisture will work
on shear and instability(near 1000 J/kg)to produce widespread
showers and a threat for thunderstorms. Given the high moisture
levels, localized heavy rainfall will be possible with any
embedded storms.

As for timing, isolated showers will begin impacting SE CA and SW
AZ as early as late Saturday. Saturday night, expecting showers
to really ramp up across that area. We`ll have to monitor how
early day showers impact instability later into Sunday, but
thunderstorms could be fairly widespread across the region Sunday
afternoon and evening as the system moves into the area. If we
are able to realize the full CAPE, some strong storms will be
possible.

As this system weakens and lifts northeast of the area early
Monday, most areas will dry out. However, a secondary upper low is
forecast to dig to our west across CA and move across the area
Tuesday. This system could act on lingering moisture for more
showers into Tuesday. After which, a drier southwest flow will
return with things heating back up, well above normal by next
weekend.

For a climate perpective, the timing of this event is quite
unusual as we are within our climatological driest time of year.
For some perspective, Phoenix Sky Harbor has only seen measurable
rainfall on 38 separate days during the last week of May and the
first week of June since 1896. The last few times Phoenix recorded
measurable rainfall during this period was in 2015, 2008, 1994,
and 1992. The highest amount recorded during this period was 0.41"
on June 3, 1915. For June 1st, Phoenix has only seen measurable
rainfall one time (1914). It is even more unusual for Yuma to see
any rainfall in the last week of May or in the first week of June
as it has only occurred on 11 separate days.

&&

.AVIATION...Updated at 1800Z.

South Central Arizona including KPHX, KIWA, KSDL, KDVT:
Winds will continue to follow their typical diurnal tendencies,
with wind speeds mostly staying under 10 kts. Light and variable
winds are expected at times as well, particularly during diurnal
transitions. Another surge of southwest winds is expected between
05-10Z, with potential for sustained speeds up to 10-14 kts and
gusts to around 20-25 kts. A TEMPO group has been added to the
KPHX and KDVT TAFs to account for this surge in winds. SCT mid
and high clouds will become BKN tomorrow morning.

Southeast California/Southwest Arizona including KIPL and KBLH:
Winds at KIPL will predominantly favor the SE, while directions at
KBLH will favor the S-SW. Wind speeds will generally be aob 10 kt.
Increasing mid and high clouds are expected through the period.

&&

.FIRE WEATHER...
Hot and dry conditions will persist into Saturday before an
unseasonably wet weather system will track through the area
Sunday. This system will bring 60-80% chances for wetting rain to
the eastern districts of South-Central Arizona and 30-60% chances
over much of the western districts. Afternoon MinRHs will
increase from mostly teens on Saturday, with MinRHs staying
elevated Sunday, mostly in the 30 percent range with excellent
overnight recoveries Sunday night. Winds will favor typical
diurnal tendencies through Saturday with some late day breeziness.
After Sunday, expect temperatures to warm and humidities to
gradually decrease, returning to more typical levels by the latter
half of next week.

&&

.PSR WATCHES/WARNINGS/ADVISORIES...
AZ...None.
CA...None.
&&

$$

DISCUSSION...Frieders
AVIATION...Berislavich
FIRE WEATHER...Kuhlman/Frieders