553
FXUS65 KPSR 300501
AFDPSR

Area Forecast Discussion
National Weather Service Phoenix AZ
1001 PM MST Sun Sep 29 2024

.UPDATE...Updated 06z Aviation Discussion...

&&

.SYNOPSIS...
Record heat will continue over the next week across the region, as
Excessive Heat Warnings are in effect through Friday evening.
Temperatures will start to cool slightly starting this upcoming
weekend, but no significant relief from the hot conditions are
expected for the foreseeable future.

&&

.DISCUSSION...
High pressure continues to dominate across the region, with mostly
clear skies prevailing across the region this afternoon. Better
cumulus fields are building across the White Mountains today
relative to the last few days, as moisture levels are increasing
slightly. Thus, some increasing cloudiness can be expected to
build into the eastern fringes of the forecast area over the next
couple of days, but rain chances remain very low (<10%).
Otherwise, the main story continues to be the record heat that
will continue to have a firm grip over the region for the
foreseeable future.

The daily record high temperature has been broken once again for
central Phoenix for today, stretching the streak to six
consecutive days of the daily record high temperature being
broken. Ridging continues to dominate over the region, with very
dry conditions creating the combo for temperatures to really
skyrocket during the daytime hours. This ridging will remain
entrenched over the region for the next week, with no real threat
of any troughing energy breaking down this ridge. Thus, the
forecasted high temperatures for the next seven days for central
Phoenix will continue to run generally 10-15 degrees above
normal, with the daily high record being broken each day. The
Excessive Heat Warnings across the region continue through at
least Friday, with these warnings likely to extend into this
upcoming weekend.

&&

.AVIATION...Updated at 0500Z.

South Central Arizona including KPHX, KIWA, KSDL, and KDVT:
No major aviation weather concerns are expected through the TAF
period. Wind directions will exhibit the more typical diurnal
tendencies with light speeds aob 8 kts. There will likely be
periods of directional variability, especially during the diurnal
transition. FEW-SCT mid-level cloud decks will be common through
Monday.


Southeast California/Southwest Arizona including KIPL and KBLH:
No major aviation weather concerns under mostly clear skies are
expected through the TAF period. At KIPL, winds out of the west
currently will switch out of the southeast during the overnight
hours and remain out of the southeast through the remainder of
the period. At KBLH, winds will vary between the south to
southwest throughout the period. Extended periods of very light
and variable winds will be common.

&&

.FIRE WEATHER...
Hot, dry weather conditions will continue with temperatures
remaining well above normal into next week as a strong ridge of high
pressure remains situated over the region. Temperatures through most
of this week will hover between 105-111 degrees across the lower
deserts. Min RHs will range around 5-15% each day. Max RHs will
range around 25-45% for most places, with locally higher values to
around 60% across Yuma and Imperial Counties. Winds will remain
fairly light generally following diurnal patterns with the exception
of some breezier conditions today with gusts upwards of 20-25 mph
later this morning through the afternoon.

&&

.CLIMATE...

Record highs this weekend and next week:

Date        Phoenix         Yuma         El Centro
----        -------         ----         ---------
Sep 29    107 in 2003    110 in 1980    110 in 1969
Sep 30    107 in 2010    109 in 2020    108 in 2020
Oct 1     107 in 2020    110 in 1980    110 in 1980
Oct 2     107 in 1980    112 in 1980    108 in 2020
Oct 3     105 in 2020    108 in 1952    108 in 1952
Oct 4     105 in 2020    109 in 1952    106 in 1952
Oct 5     105 in 2020    108 in 1917    106 in 2020
Oct 6     105 in 1917    108 in 1980    106 in 1964

&&

.PSR WATCHES/WARNINGS/ADVISORIES...
AZ...Excessive Heat Warning until 8 PM MST Friday for AZZ530>544-546-
     548>551-553>555-559.

CA...Excessive Heat Warning until 8 PM PDT Friday for CAZ562-566-567-
     569-570.

&&

$$

DISCUSSION...Young
AVIATION...Lojero
FIRE WEATHER...Smith/RW
CLIMATE...18