Severe Thunderstorm Warning 30, NWS Phoenix, AZ

829 
WWUS55 KPSR 182220
SVSPSR

Severe Weather Statement
National Weather Service Phoenix AZ
320 PM MST TUE JUL 18 2017

AZC007-013-182230-
/O.CON.KPSR.SV.W.0030.000000T0000Z-170718T2230Z/
Gila AZ-Maricopa AZ-
320 PM MST TUE JUL 18 2017

...A SEVERE THUNDERSTORM WARNING REMAINS IN EFFECT UNTIL 330 PM MST
FOR GILA AND MARICOPA COUNTIES...

At 320 PM MST, a severe thunderstorm was located over Tonto National
Monument, or near Roosevelt, moving north at 5 mph.

HAZARD...60 mph wind gusts and quarter size hail. 

SOURCE...Radar indicated. 

IMPACT...Hail damage to vehicles is expected. Expect wind damage to 
         roofs, siding, and trees. 

Locations impacted include...
Round Valley, Roosevelt, Tonto National Monument, Roosevelt Dam, Four
Peaks, Apache Lake, Tonto Basin and Tortilla Flat.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

For your protection move to an interior room on the lowest floor of a
building.

Continuous cloud to ground lightning is occurring with this storm.
Move indoors immediately. Lightning is one of nature's leading
killers. Remember, if you can hear thunder, you are close enough to
be struck by lightning.

If on or near Lake Roosevelt, get away from the water and move 
indoors or inside a vehicle. remember, lightning can strike out to 
15 miles from the parent thunderstorm. If you can hear thunder, you 
are close enough to be struck by lightning. Move to safe shelter 
now!  Do not be caught on the water in a thunderstorm.

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

&&

LAT...LON 3381 11117 3379 11113 3376 11099 3374 11096
      3365 11092 3365 11090 3347 11097 3350 11139
      3384 11151
TIME...MOT...LOC 2220Z 179DEG 5KT 3362 11107 

HAIL...1.00IN
WIND...60MPH
 
$$

Hirsch

Area Forecast Discussion
National Weather Service Phoenix AZ
156 PM MST Tue Jul 18 2017

.SYNOPSIS...
Thunderstorm potential will continue each afternoon and evening
throughout the week, with the potential for heavy rainfall,
strong wind gusts, and areas of blowing dust. Temperatures will
remain near or even slightly below seasonal normals for the rest
of the week.

&&

.DISCUSSION...
Visible satellite imagery from this afternoon shows convection is
well underway across northern and eastern Arizona. Mesoanalysis
data show an axis of 1500-2500 J/kg MLCAPE values in place between
Tucson and Phoenix, and this seems reasonable considering the
exceptional moisture in place amidst mid-upper 60s afternoon
surface dewpoints. Thermodynamically, the air mass is easily
supportive for convection to persist into the lower deserts later
this afternoon and evening. Additionally, modest easterly flow in
the midlevels is supporting sufficient effective shear magnitudes
(around 25 kt) for loosely organized multicell clusters
propagating westward this evening. High-resolution
models have become increasingly bullish for convection to develop
this evening across most of south-central Arizona.

Heavy rainfall will be the primary threat given the very high PW
values in place. Localized rainfall amounts of 1-2 inches are
possible, and a Flash Flood Watch remains in effect for all of
south-central Arizona, as well as most of La Paz County, until 2
AM MST Wednesday. Strong to locally damaging wind gusts are also a
possibility, and SPC has included most of the area in a marginal
risk for damaging wind gusts per the 20Z convective outlook
update.

The environment will remain favorable for thunderstorm development
throughout the remainder of the week as the predominant midlevel
anticyclone remains situated over the Southern Plains. Day-to-day
variability in thunderstorm activity will be greatly affected by
the preceding mesoscale evolution (e.g., cloud cover, air mass
modification from thunderstorms). However, no clear break in the
Monsoon pattern appears imminent. Temperatures will remain near
or even slightly below normal all week.

&&

.AVIATION...
South-Central Arizona including KPHX, KIWA, and KSDL:

Looking to be a very active late afternoon/evening across the
Greater Phoenix Area Today for thunderstorm development. A well-
defined weather disturbance that will be moving into the region from
the east combined with ample moisture levels will very likely
produce strong-severe thunderstorms that will be moving westward
across the Phoenix area during the 02-04Z time frame. Strong easterly
winds and very heavy rain are possible. Once the storms move
through, lighter easterly winds can be expected to continue through
the rest of the night and into early Wednesday. Wind shift back to a
westerly direction is likely on Wednesday afternoon.

Southeast California/Southwest Arizona including KIPL and KBLH:

Although most convective activity is expected to remain well east of
the SE CA terminals, there is a fair-good chance the outflows from
storms could affect KBLH later this evening. Otherwise, southerly
winds to prevail at KBLH and southeasterly winds at KIPL through the
taf period.

Aviation discussion not updated for amended TAFs.

&&

.FIRE WEATHER...
Wednesday through Sunday:

Monsoon moisture will gradually decrease through Wednesday which
will generally confine thunderstorms to the higher elevations
north and east of Phoenix during the afternoon. Although storms
around Phoenix on Wednesday cannot be ruled out entirely.
Moisture will gradually increase into the weekend and through the
early part of next week which will increase thunderstorm coverage
and possibly bringing a chance of precipitation to all lower
desert locations by early next week. Each day, minimum relative
humidity will range from 20-30% (40% in the higher elevations of
Gila county) with good overnight recoveries. Typical summertime
breezes can be expected except near thunderstorm outflows.

&&

.SPOTTER INFORMATION STATEMENT...
Spotters should follow standard reporting procedures.

&&

.PSR WATCHES/WARNINGS/ADVISORIES...
AZ...Flash Flood Watch through late tonight for AZZ533-534-537>563.

CA...None.
&&

Visit us on Facebook, Twitter, and at weather.gov/phoenix

DISCUSSION...Rogers
AVIATION...Percha
FIRE WEATHER...Wilson

PRELIMINARY LOCAL STORM REPORT
NATIONAL WEATHER SERVICE PHOENIX AZ
922 AM MST TUE JUL 18 2017

..TIME...   ...EVENT...      ...CITY LOCATION...     ...LAT.LON...
..DATE...   ....MAG....      ..COUNTY LOCATION..ST.. ...SOURCE....
            ..REMARKS..

1100 PM     TSTM WND DMG     1 SE GLOBE              33.38N 110.77W
07/17/2017                   GILA               AZ   LAW ENFORCEMENT

            TREES KNOCKED DOWN.

&&

MP

PRELIMINARY LOCAL STORM REPORT
NATIONAL WEATHER SERVICE PHOENIX AZ
935 AM MST TUE JUL 18 2017

..TIME...   ...EVENT...      ...CITY LOCATION...     ...LAT.LON...
..DATE...   ....MAG....      ..COUNTY LOCATION..ST.. ...SOURCE....
            ..REMARKS..

1100 PM     FLASH FLOOD      4 SSW GLOBE             33.34N 110.80W
07/17/2017                   GILA               AZ   LAW ENFORCEMENT

            HEAVY DEBRIS AND WATER WASHING OVER BRIDGE
            IN UPPER ICE HOUSE CANYON NEAR 9758 ICE
            HOUSE CANYON ROAD. DELAYED REPORT.

&&

MS

PRELIMINARY LOCAL STORM REPORT
NATIONAL WEATHER SERVICE PHOENIX AZ
1031 AM MST TUE JUL 18 2017

..TIME...   ...EVENT...      ...CITY LOCATION...     ...LAT.LON...
..DATE...   ....MAG....      ..COUNTY LOCATION..ST.. ...SOURCE....
            ..REMARKS..

1205 AM     FLASH FLOOD      GLOBE                   33.39N 110.79W
07/18/2017                   GILA               AZ   OTHER FEDERAL

            RAPID RISE OF WATER IN PINAL CREEK IN CLOSE
            PROXIMITY TO GILA COUNTY RV PARK. WATER
            REMAINED WITHIN THE BANKS OF THE CREEK BUT
            WAS SWIFTLY FLOWING AND APPROACHED BANKFULL
            CAPACITY. DELAYED REPORT.

&&

MS

PRELIMINARY LOCAL STORM REPORT
NATIONAL WEATHER SERVICE PHOENIX AZ
138 PM MST TUE JUL 18 2017

..TIME...   ...EVENT...      ...CITY LOCATION...     ...LAT.LON...
..DATE...   ....MAG....      ..COUNTY LOCATION..ST.. ...SOURCE....
            ..REMARKS..

1200 AM     FLASH FLOOD      1 E CLAYPOOL            33.41N 110.82W
07/17/2017                   GILA               AZ   PUBLIC

            LOW WATER CROSSING CLOSED NEAR COBRE VALLEY
            COMMUNITY HOSPITAL. DEPTH OF FLOW IN RUSSELL
            GULCH AT LOW WATER CROSSING ONE FOOT DEEP
            AND 100 FEET WIDE.

&&

MS

Special Weather Statement
National Weather Service Phoenix AZ
224 PM MST TUE JUL 18 2017

AZZ547-552-556-558-182215-
Tonto Basin AZ-Superior AZ-Rio Verde/Salt River AZ-
Pinal/Superstition Mountains AZ-
224 PM MST TUE JUL 18 2017

...SIGNIFICANT WEATHER ADVISORY FOR GILA...MARICOPA AND PINAL
COUNTIES UNTIL 315 PM MST...

At 224 PM MST, Doppler radar was tracking a strong thunderstorm 9
miles north of Top-Of-The-World, or 13 miles north of Superior,
moving west at 5 mph.

Half inch hail and wind gusts of 50 to 55 mph will be possible with
this storm.

Locations impacted include...
Roosevelt, Roosevelt Dam and Tonto National Monument.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

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

Frequent cloud to ground lightning is occurring with this storm.
Lightning can strike 10 miles away from a thunderstorm. Seek a safe
shelter inside a building or vehicle.

&&

LAT...LON 3354 11093 3337 11099 3337 11133 3372 11119
TIME...MOT...LOC 2124Z 106DEG 6KT 3348 11105

Hirsch