Sierra Vista, Arizona 7 Day Weather Forecast

Wx Forecast - Wx Discussion - Wx Aviation

012
FXUS65 KTWC 272114
AFDTWC

Area Forecast Discussion
National Weather Service Tucson AZ
214 PM MST Sun Jul 27 2025

.SYNOPSIS...Hot temperatures are expected again today across
southeastern Arizona. Moisture will begin to move in to far
southeastern areas this evening, then become widespread Monday.
Daily chances for monsoon activity will arrive with this moisture
through this week. Flash flooding, blowing dust, and damaging wind
gusts will be possible with thunderstorms this week.

&&

.KEY MESSAGES...

-Isolated thunderstorm activity this evening may produce blowing
 dust in far eastern areas near the New Mexico border.

-Moisture will increase across southeastern Arizona Monday through
 the remainder of the week. Daily chances for thunderstorms with
 the threat of flash flooding, blowing dust, and damaging wind
 gusts arrive with this moisture.

-Temperatures remain above normal today and tomorrow before
 dipping closer to normal as moisture increases this week.

&&

.DISCUSSION...The 21Z visible satellite have clouds building up
in the Chiricahuas and east into New Mexico. This will be the main
story for today. There is an inch precipitable water content on
the other side of the state line whereas we have 0.66 inches.
Plus, there is higher instability to help with thunderstorm
growth. (We have zilch instability in our area.) This will lead to
thunderstorm outflows from the east and impacting areas near the
International Border and the New Mexico state line. HREF and other
convective allowing models show outflows penetrating into eastern
side of the region, as far as Willcox. Therefore, 10-30% chance
for strong gusts above 35 mph from the line of Duncan to Douglas
this late evening. Blowing dust is possible since it has been
fairly dry and hot for the last several days.

Tonight, the easterly push coupled with any outflows will boost
our dew points up by 10-25 degrees and our precipitable water
content will also climb up to 1 inch to 1.5 inches, typical
monsoon moisture for this time of year. Model guidance have
agreement on thunderstorms forming east of Tucson, especially
along the White Mountains to Mt Graham, and spreading southwest to
west across the region.

Gusty winds will be the primarily threat for the day. We will
have high instability and hot temperatures to initiate
thunderstorms. Forecasted skew-ts have CAPE and DCAPE values in
the 1200-1500 J/KG in the Upper Gila River Valley. The inverted V
profile is ripe for strong gusty winds. Even the ensemble models
have high probabilities (70%) for strong gusty winds from the
White Mountains to Mt Graham. With that, expect strong gusty winds
of 45 mph with localized areas experiencing severe level winds
from any thunderstorm coming off the high terrain. Especially
within the Gila River Valley and along the Interstate 10 of
Cochise County.

Tuesday through Wednesday, the easterly push will be around, in a
form of a wave, morphing into a mesoscale convective vortex (MCV)
after Monday night. Convective allowing models have the MCV, but
differ on the location and evolution of storm development for
Tuesday and even Wednesday. This follows the typical pattern of
the monsoon of up days, down days, or just some rainy days.
Chances for daily thunderstorms will exist through the remainder
of the week. A daily risk for gusty winds and flash flooding.

Next weekend, we will dry out slightly, but enough moisture to
bring slight chances for thunderstorms. Our precipitable water
will be around an inch with dew points in the 45-50 degrees range.
The higher terrain will be the favorite locations for storm
chances.


&&

.AVIATION...Valid through 29/00Z.
Few to scattered cirrus through throughout the forecast period.
Cumulus build-ups near and east of KTUS-KOLS this afternoon and
evening with a slight chance of a thunderstorm from near and east
of KSAD- KDUG. Gusty and erratic winds with pockets of blowing
dust possible under any thunderstorm. Otherwise winds generally
light and terrain driven through the period. Tomorrow, after
28/18Z, will have scattered to broken clouds at or around 10-12k
ft AGL due to isolated to scattered thunderstorms across the
region. Aviation discussion not updated for TAF amendments.


&&

.FIRE WEATHER...Hot and dry conditions this afternoon with min RHS
in the 8-15 percent. Monsoon moisture will be moving into the
region later this evening, providing daily chances for rain
showers and thunderstorms through the week. Surface winds will
generally be less than 12 mph through the week. Any thunderstorm
has the potential to produce strong gusty and erratic winds. With
the increase monsoon moisture from the east, starting Monday, min
RHs will generally be above 20 percent across the region with
good overnight recoveries of 50 percent or higher. Temperatures
will be hovering around seasonal normal for the week. Next weekend,
monsoon moisture will wane a bit but there will enough moisture
to provide daily to slight chances for rain showers and
thunderstorms.


&&

.TWC WATCHES/WARNINGS/ADVISORIES...
None.
&&

$$


Visit us on Facebook...Twitter...YouTube...and at
weather.gov/Tucson