102
FXUS65 KTWC 311018
AFDTWC

Area Forecast Discussion
National Weather Service Tucson AZ
318 AM MST Fri Jul 31 2026

.SYNOPSIS...Expect a downturn in thunderstorm activity through
today with isolated storms south and east of Tucson. Storm
coverage and chances increasing Saturday, but especially next
week. High temperatures will be 10-15 degrees above normal into
the weekend with an Extreme Heat Warning in effect through
Sunday.

&&

.DISCUSSION...
Overnight an MCS (Mesoscale Convective System) moved through
Cochise and Santa Cruz counties, with its current position over
Santa Cruz county. Behind this system, there will be subsidence
left in its wake, delaying and/or limiting today`s afternoon and
evening storms in these areas. Outside of these areas, the best
chances for storms are in the White Mountains.

Saturday looks to be shaping up to be an increase in
thunderstorm activity, with SPC introducing an area of marginal
risk for severe winds for areas east of Tucson. The high
pressure moves from overhead to northward, introducing SW flow
aloft. The 31/00Z HREF is showing an area of probability of 10%
wind gusts 50kts/58mph along the AZ/NM border in Graham,
Greenlee and Cochise counties. With the placement of these
probabilities, blowing dust can be an issue along I-10 from San
Simon to Willcox and in Cochise county. Isolated areas of flash
flooding due to locally heavy rainfall and/or training
thunderstorms over the same areas is possible, but not the main
impact expected Saturday.

The high pressure continues to meander generally near northern
Arizona, keeping Southeast Arizona under SW flow into early next
week, keeping daily chances for showers and thunderstorms each
afternoon and evening.

Outside of storm chances, the Extreme Heat continues through the
weekend with temperatures 10-15 degrees above normal with near
to record breaking heat each day. Continue to practice heat
safety by staying indoors (with AC when possible) during peak
heating, staying hydrated, consider moving plans indoors,
knowing the signs for heat illness, and checking in on
vulnerable populations over the coming days.

&&

.AVIATION...Valid through 01/12Z.
FEW-SCT 8k-12k ft AGL for much of the period. Isolated TSRA
will be possible 31/21Z-01/06Z with KDUG terminal having the
best chance to be impacted by TSRA, KOLS could see TSRA as well.
Gusty SFC winds near TSRA with wind gusts up to 35 kts will be
possible. SFC winds NWLY 8-12 kts from 31/18Z thru 01/03Z with
occasional gusts up to 25 kts. Otherwise, SFC winds light and
variable under 10 kts. Aviation discussion not updated for TAF
amendments.

&&

.FIRE WEATHER...
High temperatures will remain well above normal this through
Sunday with an Extreme Heat Warning in effect through Sunday.
Expect daily chances of afternoon and evening showers and
thunderstorms mainly south and east of Tucson through the
weekend with some day to day variability in coverage. Early
next week storm coverage and chances are expected to increase.
Any thunderstorm will bring a threat of severe, erratic wind
gusts as well as brief heavy rainfall and an isolated threat of
flash flooding. Min RH values will be 10-20 percent through
Saturday then 15-30 percent Sunday into next week. Winds will be
terrain driven at 5 to 10 mph with occasional gusts up to 25
mph.

&&

.CLIMATE...

RECORD OR NEAR RECORD HIGH TEMPERATURES NEXT 2 DAYS

DATE                         Jul 31           Aug 01
                           FCST RCD/YR      FCST RCD/YR
TUCSON INTL AIRPORT       111  111 / 1926   112  112 / 1993
AJO                       111  117 / 1995   112  114 / 1972
KITT PEAK                  91   89 / 1995    92   96 / 2021
ORGAN PIPE CACTUS         110  114 / 1986   111  113 / 1997
PICACHO PEAK              107  114 / 1996   108  114 / 1993
SAFFORD AG STATION        110  108 / 1995   107  108 / 1986
SIERRA VISTA FD           103  104 / 2020   101  103 / 2020
TOMBSTONE                 102  106 / 2020   101  105 / 1944
WILLCOX                   106  107 / 2020   104  108 / 2020

RECORD OR NEAR RECORD HIGH TEMPERATURES DAYS 3 & 4

DATE                           Aug 02           Aug 03
                            FCST RCD/YR      FCST RCD/YR
TUCSON INTL AIRPORT       110  110 / 1918   107  110 / 1994
AJO                       112  115 / 1972   109  115 / 2021
KITT PEAK                  91   91 / 1995    89   90 / 1995
ORGAN PIPE CACTUS         110  113 / 1994   108  114 / 1998
PICACHO PEAK              107  111 / 1995   106  112 / 1998
SAFFORD AG STATION        105  108 / 2024   107  107 / 2025
SIERRA VISTA FD            98  103 / 2020    98  100 / 1995
TOMBSTONE                  99  105 / 1944    99  105 / 1995
WILLCOX                   101  104 / 1944   103  105 / 1944

&&

.TWC WATCHES/WARNINGS/ADVISORIES...
Extreme Heat Warning until 8 PM MST Sunday for AZZ501>509.

&&

$$

JT

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