Special Weather Statement, NWS Tucson, AZ

Area Forecast Discussion
National Weather Service Tucson AZ
209 PM MST Sun Aug 2 2020

.SYNOPSIS...The strong ridge of high pressure responsible for our
hotter than average temperatures will gradually weaken in the coming
days, although the hotter than normal temperatures will continue
through next week. Isolated to scattered thunderstorms will develop
each afternoon as well, though Monday and Tuesday look to be a little
less active compared to the rest of the week.

&&

.DISCUSSION...Thunderstorms erupted over the White Mountains on
schedule although it is running just about an hour or so behind
elsewhere. The slower heating thanks to the thick smoke layer
overhead slowed things up. Starting to see convection starting to
bubble over a few of the east sky island areas at this time and would
expect this to continue over the next hour or two. Then we should
see isolated to scattered convection about the area mainly east,
south and potentially southwest of Tucson although likely not as
vigorous as it could have been without the dense smoke layer. Any
convection that develops should shut down by midnight.

The upper high will center itself over the area Monday as it slowly
oozes eastward which will help to suppress the convection, generally
confining it to the international border area and up over the White
mountains. Temperatures will be quite warm and flirting with heat
warning thresholds but opted to not go that route at this time. If
the Apple Fire in California has another active burn period later
today, smoke could impact our temperatures again tomorrow afternoon.

For Tuesday into Wednesday, the center of the high will continue to
move east with an upper trough moving onto the west coast. This will
induce just enough of a southerly flow that we should be able to
spread thunderstorms just a bit further north Tuesday and even more
so Wednesday. This will result in a trimming of the afternoon
temperatures by a few degrees.

By Thursday and/or Friday depending on timing, the upper trough
strengthens along the west coast increasing the southwest flow aloft
over the area which will eventually force the moisture over the area
off to the east if this comes to pass. However during the transition
of having lingering moisture and stronger mid-level flow could make
for more organized convection We will see how that plays out with
time.

The drier southwest flow looks to linger through next weekend at
this time which would translate into drier and warmer conditions once
again with any convection confined fairly close to the southern
and/or eastern border areas.

&&

.AVIATION...Valid through 04/00Z.
FEW-SCT clouds (locally BKN) at 10k-15k ft MSL much of the period.
Isolated to scattered -TSRA/-SHRA into this evening. Wind gusts to
near 45 kts may occur at times with the stronger -TSRA. Otherwise,
NWLY SFC wind at 8-14 kts with gusts around 20 kts into this evening.
The strongest speeds will occur in the Upper Gila River Valley near
KSAD. Winds decrease overnight to less than 10 kts. Isolated
-TSRA/-SHRA return Monday afternoon south and east of KTUS with sfc
wind WLY/NWLY mainly less than 12 kts. Aviation discussion not
updated for TAF amendments.

&&

.FIRE WEATHER...Hot temperatures continue this week. Expect isolated
to scattered mainly afternoon and evening thunderstorms favoring
locations east to south of Tucson through Tuesday. Coverage of
thunderstorms extends further westward by midweek to include much of
the area. By the weekend, thunderstorms will once again be limited to
areas east to south of Tucson. Except for some slightly elevated
20-foot northwest winds in the upper Gila River valley through
Monday, 20-foot winds winds will generally follow typical diurnal
trends at less than 15 mph apart. However, thunderstorms may produce
wind gusts in excess of 40 mph.

&&

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

Public...Cerniglia
Aviation...Carpenter
Fire Weather....Carpenter

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

Special Weather Statement
National Weather Service Tucson AZ
209 PM MST Sun Aug 2 2020

AZZ510-022145-
White Mountains of Graham and Greenlee Counties including Hannagan
Meadow-
209 PM MST Sun Aug 2 2020

...SIGNIFICANT WEATHER ADVISORY FOR NORTH CENTRAL GRAHAM AND
NORTHWESTERN GREENLEE COUNTIES UNTIL 245 PM MST...

At 208 PM MST, Doppler radar was tracking a strong thunderstorm 9
miles west of Hannagan Meadow, or 38 miles south of Springerville,
moving southwest at 15 mph.

Penny size hail and wind gusts up to 50 mph will be possible with
this storm.

This storm will remain over mainly remote areas of north central
Graham and northwestern Greenlee Counties.

LAT...LON 3360 10937 3340 10951 3351 10974 3352 10973
      3354 10968 3358 10967 3359 10962 3361 10960
      3362 10957 3362 10953 3367 10948
TIME...MOT...LOC 2108Z 059DEG 14KT 3361 10949

AH

Special Weather Statement
National Weather Service Tucson AZ
445 PM MST Sun Aug 2 2020

AZZ509-030015-
Upper Gila River and Aravaipa Valleys including Clifton/Safford-
445 PM MST Sun Aug 2 2020

...SIGNIFICANT WEATHER ADVISORY FOR CENTRAL GRAHAM COUNTY UNTIL 515
PM MST...

At 445 PM MST, Doppler radar was tracking a strong thunderstorm 8
miles northwest of Thatcher, or 11 miles northwest of Safford, moving
southeast at 5 mph.

Dime size hail and wind gusts up to 50 mph will be possible with this
storm.

Locations impacted include...
Safford, Thatcher, Safford Regional Airport, Pima, Central and Fort
Thomas.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

Heavy rainfall is also occurring with this storm, and may lead to
localized flooding. Do not drive your vehicle through flooded
roadways.

&&

LAT...LON 3276 10973 3296 11009 3309 10996 3287 10957
TIME...MOT...LOC 2345Z 297DEG 5KT 3291 10988