153
FXUS65 KPSR 142305
AFDPSR

Area Forecast Discussion
National Weather Service Phoenix AZ
405 PM MST Sat Mar 14 2026

.UPDATE...
Updated Aviation

&&

.KEY MESSAGES...

- Strong high pressure will keep temperatures well above normal
through the start of next week.

- An unprecedented heat wave for March with widespread triple digits
will arrive by Wednesday across lower elevations, and readings near
105 degrees in major metropolitan areas by Thursday shattering daily
records by as much as 10 degrees.

- An Extreme Heat Watch has been issued for Wednesday morning for
Southeast California, then expanding Thursday morning into southern
Arizona.


&&

.SHORT TERM /TODAY THROUGH MONDAY/...
Satellite imagery shows the expected quasi-zonal flow now set up
over the Desert SW as strong ridging begins to build just off the
West Coast. However, positive height anomalies still influence the
region today through Monday, continuing the above normal high
temperatures across the region and especially in the lower desert
areas. Today afternoon highs in the lower deserts will be in the low
to mid 90s. High temperatures will cool 1-2 degrees on Sunday, then
by Monday the core of the ridge begins to move onshore, which will
drive temperature back into the low to mid 90s. These temperatures
are 10-15 degrees above normal, for this time of year.

Before the aforementioned strong ridge off the West Coast migrates
over Western CONUS, a very subtle shortwave trough will pass through
the region. This will not only be a reason temperatures cool
slightly over the weekend, but it will tighten the pressure gradient
over the region causing breezy to locally windy conditions. The
strongest gusts are expected to be between 25-30 mph along the Lower
Colorado River Valley, but ridge tops can be upwards of 35 mph at
times. The main timeframe for the breezy to windy conditions will be
Sunday and Monday afternoon into the early evening hours, and will
subside after the sunset.

&&

.LONG TERM /TUESDAY THROUGH NEXT SATURDAY/...
The area of high pressure suppressed and shoved westward by the
transient disturbance will rebound and eventually migrate off the
Eastern Pacific by Tuesday. As it moves, regional H5 heights will
rise markedly, reaching near 588-590dm. However, global
deterministic guidance takes things further showing heights aloft
peaking near 594-596dm by Thursday. For reference, sounding
climatology data for Las Vegas, Flagstaff, and Tucson all show
record H5 heights for March are around 590dm and April 591dm, 593dm,
and 592dm respectively. With that being said, this high will be near
to slightly stronger than any ridge this region has seen in recorded
history, not only for March, but for April as well.

This anomalously strong high will translate to record temperatures,
not just at the surface, but throughout much of the atmosphere as
well. H7-H5 temperatures will reach all-time records for this time
of year by Tuesday, with H8 readings joining the fray by Wednesday.
These climatological records will not last one day either as
forecasts show these abnormal values extending through the end of
the work week and even into next weekend. At the surface, lower
desert highs by Tuesday will be in the upper 90s to near 100 degrees
with values climbing to around 105 degrees for much of the lower
deserts by Thursday. If these temperatures are realized, those
readings would be 25 to almost 30 degrees above normal.

It should not come as much of a surprise that numerous records are
likely to be broken at some point next week with Tuesday likely
being the first day when all-time daily MaxTs begin to fall.
However, with the lack of movement from the ridge overhead,
consecutive days with new record temperatures appear likely. What is
also very unusual about how hot this pattern will be is how much
high temperatures could potentially best previous records. For
instance, the current forecasted high temperature for Phoenix for
Friday is 106 degrees. While it is typical to see records beaten by
a few degrees at most, this forecast high may beat Fridays record of
96 by 10 degrees. Monthly records are also at risk of falling during
this upcoming heat wave. The all-time March records for Phoenix,
Yuma, and El Centro are 100, 102, and 101 degrees respectively. All
of those values could be tied or eclipsed as early as Wednesday.

The record setting potential doesn`t end there. The earliest 100
degree day recorded in Phoenix is March 26, which was observed back
in 1988, and is actually the only other time since records began
when triple digits were achieved in the month of March for the city.
It appears that a new earliest instance of 100 degree will be set as
it is a matter of when, not if, it will happen. Current forecasts
suggest that will occur on Wednesday the 18th, 8 days ahead of the
previous record. Fortunately, the earliest triple digit readings for
Yuma and El Centro are March 12th and 15th respectively, so those
records are very much safe for at least another year (and hopefully
much longer). Nonetheless, the average first 100 degree readings for
these locations is late April, so we will be almost a month and half
ahead of schedule.

Moderate HeatRisk will develop in response to the upcoming abnormal
heat, with even some localized areas of Major HeatRisk not out of
the question. Therefore, an Extreme Heat Watch has been issued for
the Lower Colorado River Valley and westward starting Wednesday,
which will expand to include much of Southern Arizona by Thursday.

&&

.AVIATION...Updated at 2305Z.

South Central Arizona including KPHX, KIWA, KSDL, and KDVT; and
Southeast California/Southwest Arizona including KIPL and KBLH:

No major weather issues will exist through Sunday evening as high
cirrus decks gradually clear. Confidence is excellent that west
winds in the Phoenix metro will revert to an easterly component
mid/late evening. Behavior of winds Sunday will be very similar to
today. In SE California, a W/SW wind component should become more
northerly Sunday with gusts 20-25kt common at KBLH.

&&

.FIRE WEATHER...
High pressure will result in temperatures 10-15 degrees above normal
today through Monday before increasing to 25-30 degrees above normal
by the middle portion of next week. Abnormally hot and very dry
conditions will translate to MinRH near or just below 10% with poor
overnight recovery as MaxRHs will only be expected to to run near 20-
40%. Increasing breeziness will be observed through this weekend,
mainly over the Arizona high terrain and the Lower Colorado River
Valley, with the strongest gusts (25-35 mph) focused over the latter
area. The breezy conditions, combined with low RH values will result
in elevated to isolated areas of critical fire weather conditions.
However, with the limited scope of enhanced winds, no fire weather
products are needed at this time.

&&

CLIMATE...

Daily record highs through next weekend:

Date      Phoenix         Yuma         El Centro
----      -------         ----         ---------
3/14     95 in 2013     96 in 2017     97 in 2017
3/15     92 in 2013     98 in 1934    100 in 1934
3/16     99 in 2007     99 in 2007    100 in 2007
3/17     99 in 2007    101 in 2007    101 in 2007
3/18     95 in 2017     96 in 2017     95 in 2007
3/19     96 in 2017     98 in 2017     96 in 2017
3/20     96 in 2017     99 in 2004     98 in 2004
3/21     97 in 2004    102 in 2004    100 in 2004
3/22     94 in 1990     98 in 2004     96 in 2004

&&

.PSR WATCHES/WARNINGS/ADVISORIES...
AZ...Extreme Heat Watch from Wednesday morning through Sunday evening
     for AZZ530.

     Extreme Heat Watch from Thursday morning through Sunday evening
     for AZZ531>544-546-548>551-553>555-559.

CA...Extreme Heat Watch from Wednesday morning through Sunday evening
     for CAZ561>570.

&&

$$

SHORT TERM...Ryan
LONG TERM...RW
AVIATION...18
FIRE WEATHER...RW/Ryan
CLIMATE...18/Kuhlman

NWS Phoenix (PSR) Office