699
FXUS65 KPSR 102059
AFDPSR

Area Forecast Discussion
National Weather Service Phoenix AZ
159 PM MST Thu Sep 10 2026

.KEY MESSAGES...

- Above normal temperatures will prevail through the rest of the
  week, with Extreme Heat Warnings in effect for portions of the
  lower deserts.

- Daily chances for scattered showers and isolated thunderstorms
  will continue to be focused over the Eastern Arizona high
  terrain. Any chances for lower deserts should be confined to
  late Friday and again Sunday into Monday.

- Cooling temperatures over the weekend into early next week
  should eventually push readings back into the normal range by
  around next Tuesday.

&&

.SHORT TERM /TODAY THROUGH FRIDAY/...
The high remains centered over southwestern AZ and southeastern
CA with generally easterly flow aloft over the region. Mid to high
level moisture has stayed put with 1000-700 mb mixing ratios
still ranging between 10-12g/kg across the lower deserts and into
the eastern high terrain. While we have plenty of moisture (PWATs
140-160% of normal), with a strong lower level subsidence
inversion in place convection will struggle to have any
development for most areas, especially after SE AZ had extensive
activity last night, which may have overworked the atmosphere too
much for anything developing tonight. This is reflected in the
latest CAMs and HREF showing 544-546-548>551-559.

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

&&

$$

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

NWS Phoenix (PSR) Office