Flash Flood Warning 87, NWS Tucson, AZ

854 
WGUS75 KTWC 130030
FFSTWC

Flash Flood Statement
National Weather Service Tucson AZ
530 PM MST Mon Aug 12 2024

AZC019-023-130145-
/O.CON.KTWC.FF.W.0087.000000T0000Z-240813T0145Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/
Pima AZ-Santa Cruz AZ-
530 PM MST Mon Aug 12 2024

...FLASH FLOOD WARNING REMAINS IN EFFECT UNTIL 645 PM MST THIS 
EVENING FOR EAST CENTRAL PIMA AND NORTHWESTERN SANTA CRUZ COUNTIES...

At 530 PM MST, Doppler radar indicated thunderstorms which produced 
heavy rain near and south to southeast of Green Valley has subsided. 
Between 1 and 2 inches of rain have fallen. Flooding impacts will 
continue, but no additional rainfall is expected. Flash flooding is 
ongoing or expected to begin shortly.

HAZARD...Life threatening flash flooding. Thunderstorms producing
         flash flooding.

SOURCE...Radar.

IMPACT...Life threatening flash flooding of creeks and streams,
         urban areas, highways, streets and underpasses.

Some locations that will experience flash flooding include...
  Sahuarita, Green Valley, Amado and Arivaca Junction.

This includes Interstate 19 between mile markers 29 and 40.

This includes the following streams and drainages...
  Old Junction Wash, Sopori Wash, Demetrie Wash and Santa Cruz River.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

Turn around, don't drown when encountering flooded roads. Most flood 
deaths occur in vehicles.

Be aware of your surroundings and do not drive on flooded roads.

&&

LAT...LON 3188 11104 3186 11095 3185 11096 3177 11096
      3172 11095 3169 11098 3170 11104 3171 11109
      3177 11111

FLASH FLOOD...RADAR INDICATED
FLASH FLOOD DAMAGE THREAT...CONSIDERABLE

$$

GEL

271 
WGUS75 KTWC 130146
FFSTWC

Flash Flood Statement
National Weather Service Tucson AZ
646 PM MST Mon Aug 12 2024

AZC019-023-130156-
/O.EXP.KTWC.FF.W.0087.000000T0000Z-240813T0145Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/
Pima AZ-Santa Cruz AZ-
646 PM MST Mon Aug 12 2024

...FLASH FLOOD WARNING HAS EXPIRED FOR EAST CENTRAL PIMA AND 
NORTHWESTERN SANTA CRUZ COUNTIES...

Flood waters have receded. The heavy rain has ended. Flooding is no 
longer expected to pose a threat. Please continue to heed remaining 
road closures.

&&

LAT...LON 3188 11104 3186 11095 3185 11096 3177 11096
      3172 11095 3169 11098 3170 11104 3171 11109
      3177 11111

$$

GEL

Area Forecast Discussion
National Weather Service Tucson AZ
123 PM MST Mon Aug 12 2024

.SYNOPSIS...
Scattered thunderstorms are expected through this afternoon and
evening with the potential for heavy rain and severe wind gusts.
Additional thunderstorms are likely Tuesday, with lower chances
Wednesday and Thursday. High temperatures will rise by mid-week,
though remain within a few degrees of normal.

&&

.DISCUSSION...
The overall weather pattern is being driven by an upper high over
the Southern Plains, and small scale circulation over northern
Baja California. Southern Arizona is under moist southerly flow
driven by these circulations. The atmosphere remains very moist,
elucidated by this morning's weather sounding that shows over 1.5
inches of precipitable water. Scattered showers and thunderstorms
have started developing as of this writing. With a fair bit of
instability in the atmosphere along with moisture, both severe
winds and flash flooding will be threats. There is a bit of storm
motion to these storms, and with a bit of wind shear, some of
these storms may be able to sustain themselves longer than the
usual pulse storms. Considering all threats and probabilities,
today appears to be a "moderate risk" day...or 3 on a scale of 1
to 5 of potential monsoon impacts.

Tuesday's weather will likely depend somewhat on how the
convection evolves today. That being said, the axis of moisture
does shift eastward slightly on Tuesday, and the potential areas
of impact should follow.

An upper high centered over the eastern Pacific should build
overhead on Wednesday and Thursday. This will effectively cut off
the southerly moisture tap from the Sierra Madres, and enhance
subsidence across the region. This should result in a couple days
of drier and hotter weather. At this stage, it looks like
temperatures should remain well below the High HeatRisk category
that would prompt Excessive Heat consideration.

The upper ridge quickly slides eastward back to southcentral US
late this week. This could result in an uptick in thunderstorm
activity Friday onward.

&&

.AVIATION...Valid through 13/12Z.
Scattered to broken clouds with 7k to 10k with scattered TSRA
through around 13/03Z, with continued -SHRA possible overnight.
Visibility restrictions, gusts to 45 kts, heavy rain, and mountain
obscurations likely with any thunderstorm this afternoon and
evening. Wind outside of thunderstorms will be less than 12 kts
and favor a west to southwesterly direction. Aviation discussion
not updated for TAF amendments.

&&

.FIRE WEATHER...
Chances for thunderstorms continue this afternoon and evening as
well as Tuesday. A downturn in thunderstorm chances is likely
Wednesday and Thursday, with moisture and thunderstorms chances
returning by the weekend. Minimum relative humidity values 25 to
40 percent in the valleys through mid-week. Outside of
thunderstorm outflow winds, 20-foot winds will generally be 15 mph
or less, with afternoon/early evening gusts to 20-25 mph and
light winds overnight.

&&

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

&&

Public...Dang
Aviation...Dang
Fire Weather....Dang

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