Tempe, Arizona 7 Day Weather Forecast

Wx Forecast - Wx Discussion - Wx Aviation

380
FXUS65 KPSR 020913
AFDPSR

Area Forecast Discussion
National Weather Service Phoenix AZ
213 AM MST Wed Apr 2 2025

.SYNOPSIS...
An unsettled weather pattern will persist through the
end of the week with chances for scattered shower activity across
portions of south-central AZ, especially across the foothills and
higher terrain areas north and east of Phoenix, for today and
again on Friday. Temperatures through the end of the week will
remain well-below normal before a warming trend takes shape
starting this weekend.

&&

.DISCUSSION...
Latest water vapor satellite imagery as well as streamline analysis
shows a large upper-level trough encompassing most of the western
CONUS with the strong west to east oriented jet, that resulted the
widespread gusty winds yesterday, now situated just south of the
region over northern Mexico. However, enough of a pressure gradient
remains in place that some gusty winds will still materialize once
again this afternoon through early this evening. The strongest winds
will occur across the higher terrain areas east of Phoenix and
across western Imperial County, where some gusts ranging between 25-
35 mph will be possible at times. Elsewhere, wind gusts should be
lighter, ranging between 15-25 mph.

This troughing pattern will persist across the region through the
end of the week, resulting in well-below normal temperatures as well
as send a couple of shortwaves over the area bringing some rain
chances. One such shortwave is currently seen in water vapor
imagery over central CA and will continue to propagate southeast
into Arizona heading into this afternoon. Even though moisture
levels will remain quite meager as PWATs are only expected to
range between 0.3-0.4", the forcing for ascent in combination with
the cold temperatures aloft will be sufficient to squeeze out
the moisture available to result in the development of scattered
shower activity late this morning into this afternoon. The latest
HREF membership shows scattered shower activity developing across
portions of northern La Paz county during the late morning hours
and then pivoting eastward through northern Maricopa County,
favoring areas north and east of Phoenix during the afternoon
hours. Given the very cold temperatures aloft, steep mid-level
lapse rates will be in place to result in CAPE values of around
100-200 J/KG. Thus, any of these showers that pivot through will
be capable of containing embedded lightning strikes. Some pea
size hail cannot be ruled out as well with the stronger
convective showers. Rainfall amounts with the activity this
afternoon should remain light at less than 0.05" with locally
higher amounts possible with any thunderstorms that do develop.
High temperatures this afternoon will struggle to reach 70 degrees
across the lower deserts with most areas in south-central AZ
likely remaining stuck in middle 60s as a result of more abundant
cloud cover. Temperatures Thursday and Friday will slightly
warmup but will remain well-below normal. On Friday, another
shortwave will pivot through the region bringing another shot of
some scattered shower activity, mainly confined to the higher
terrain areas north and east of Phoenix once again.

Global ensembles are in good agreement that by this weekend the
troughing pattern will gradually weaken and eject eastward allowing
the upper-level height fields to rise as an upper-level ridge moves
into the west coast. As a result, a gradual warming trend will take
shape with high temperatures returning to near normal levels by
Sunday. Thereafter, as the ridge moves into the region early next
week temperatures will warm to above normal levels with highs
topping out around 90 degrees as early as Tuesday. By the middle to
latter half of next week, the ensembles are in very good agreement
that the ridging pattern will intensify even further, boosting
temperatures even more to well-above normal levels. In fact, there
is a good probability that by the latter half of the week many of
the lower deserts communities will observe the first triple digits
of the year.

&&

.AVIATION...Updated at 0520Z.

South Central Arizona including KPHX, KIWA, KSDL, and KDVT:
Unusual trends in wind directions, occasionally stronger gusts, and
periods of lower cigs will all be weather concerns through Wednesday
evening resulting in only low to moderate confidence of many
forecast details. Confidence is good that a widespread shift to
easterly winds will not occur tonight though some of the outer
terminals such as KIWA and KSDL may become SE or variable for a few
hours overnight and early morning. Models suggest 050-070 AGL cigs
will develop mid morning through early afternoon with a tendency for
bases to rise through the afternoon, though they may hover not far
from the 060 threshold. Another round of gusty SW winds 20-25kt is
likely mid/late afternoon. Isolated SHRA are possible around the
airspace during the late afternoon with somewhat better confidence
of greater coverage affecting some aerodromes - particularly KSDL
and KDVT. There is growing model evidence that some of these SHRA
north and west of Phoenix may create erratic winds and create a
northerly component late afternoon/early evening with low confidence
on resulting wind components Wednesday evening as cigs should begin
to scatter.

Southeast California/Southwest Arizona including KIPL and KBLH:
Gusty winds will remain the greatest weather issue through Wednesday
evening under periods of passing mid/high clouds. Westerly gusts 20-
30kt will be most pronounced in duration and magnitude at KIPL with
only a possible brief early morning period of weakening. Gusts will
be far weaker at KBLH, however wind directions may be much more
variable through the period, albeit mostly favoring a westerly
direction. There is model evidence of some lower cigs developing
during the mid morning hours at KBLH, though confidence is only low
to moderate.

&&

.FIRE WEATHER...
Some gusty winds will continue for this afternoon and early
evening, with the strongest winds across Imperial County and the
higher terrain areas east of Phoenix as gusts up to 25-35 are
anticipated. Scattered shower activity will develop this
afternoon, with the best chances confined across northern Maricopa
County north and east of Phoenix. A few isolated thunderstorms
may accompany the shower activity. The CWR, however, will remain
low at 10-20%. Another chance for showers is anticipated for
Friday, with activity confined mainly to higher terrain north and
east of Phoenix with the CWR once again expected to remain low at
10-30%. MinRHs today will range between 25-35% areawide. Generally
light winds are anticipated from Thursday onward. MinRHs will
range between 20-30% on Thursday and between 10-25% from Friday
through the weekend. Overnight recoveries will remain fair to good
on most days. Well-below normal temperatures are anticipated
through the end of the week before a gradual warming trend takes
shape beginning this weekend.

&&

.PSR WATCHES/WARNINGS/ADVISORIES...
AZ...None.
CA...Wind Advisory until 11 AM PDT this morning for CAZ562.

     Wind Advisory until 2 AM PDT early this morning for CAZ563-566-
     567.

&&

$$

DISCUSSION...Lojero
AVIATION...18
FIRE WEATHER...Lojero