FXUS65 KTWC 091022
AFDTWC

Area Forecast Discussion
National Weather Service Tucson AZ
322 AM MST Thu Jul 9 2026

.SYNOPSIS...Isolated to scattered showers and thunderstorms are
expected today and Friday, with the potential for an increase 
in storm coverage over the weekend. Hot temperatures continue
today and Friday before cooling off this weekend.

&&

.DISCUSSION...Satellite imagery this morning showed debris clouds
over across eastern half of forecast area, which will slowly 
diminish through sunrise. Satellite derived PWATs were between 
1" and 1.40". Last nights upper air plots placed the monsoon 
high west of nrn Baja with SE AZ on eastern flank of this high.

For today, isolated to scattered showers and thunderstorms this
afternoon and evening with main threats being strong gusty outflow
winds, blowing dust and localized flash flooding. HREF has 10%+
neighborhood probability (25 miles) of 50 kts for areas mainly 
E and S/SW of Tucson. SPC has most of the eastern half of the 
forecast area under marginal risk for severe wind gusts. Some of
the stronger cells will also be capable of localized heavy rain
with rain rates up to 1"/hr leading to localized flash flooding.
The main areas of concern for this will be Santa Cruz county 
and SW Cochise county. WPC has this area under marginal risk for
flash flooding. Of interest tonight will be how active will 
Sonora MX get and will the thunderstorm outflows be strong 
enough when hitting the GlfofCA to initiate a gulf surge. 

Friday: The monsoon high will lift into western Arizona keeping
the area on the eastern flank of the high. Storms, some severe,
will mostly be E and S of Tucson with HREF having 10-30% 
neighborhood probabilities (25 miles) of 50 kts. Localized heavy
rain and flash flooding will be also concern.

This weekend: With the monsoon high lifting into the northern
Rockies/Plains a more favorable monsoon flow pattern sets up
resulting in an increase in PWATs (1.2"-1.6") and flash 
flooding/severe thunderstorm risks. WPC has our area painted for
Marginal Risk for Excessive Rainfall Outlook this weekend.

Monday through Wednesday: Favorable monsoon flow will continue
daily chances of showers and thunderstorms with flash flooding 
and severe thunderstorms a daily risk.

Temperatures: One more day of the Extreme Heat Warning then
temperatures gradually cool to near normal-ish Sunday into next
week.

&&

.AVIATION...Valid through 10/12Z.
SCT clouds 8k-11k ft AGL slowly diminishing thru 09/15z, then
redeveloping aft 09/18z, bcmg SCT-BKN aft 09/23z with ISOLD to
SCTD -SHRA/-TSRA mainly E and S of KTUS. There is the potential
for outflow winds up to 45 kts btwn 09/21z and 10/03Z. Outside 
of any thunderstorm outflows, SFC wind less than 12 kts, favoring
a WLY/NWLY direction during the afternoon/early evening hours 
and variable in direction at other times. Aviation discussion 
not updated for TAF amendments.

&&

.FIRE WEATHER...Above normal high temperatures (4-7 degrees) 
through Thursday, with highs lowering to around normal over the 
upcoming weekend. Min RH values in the lower elevations in the 
13-20 percent range through Friday, increasing 5-10 percent by 
late in the weekend into early next week. Outside of any 
thunderstorm outflow winds, 20- foot winds will generally be 
less than 15 mph into early next week. There will be a daily 
chance of showers and thunderstorms mainly during the 
afternoon/evening hours through Friday. There is the potential 
for increasing thunderstorm chances and coverage this weekend 
into early next week.

&&

.TWC WATCHES/WARNINGS/ADVISORIES...
 Extreme Heat Warning until 8 PM MST this evening for AZZ501-
  502-504>506-509.

&&

$$

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