Flash Flood Warning 78, NWS Flagstaff, AZ

976 
WGUS75 KFGZ 122129
FFSFGZ

Flash Flood Statement
National Weather Service Flagstaff AZ
229 PM MST SAT AUG 12 2017

AZC005-122315-
/O.CON.KFGZ.FF.W.0078.000000T0000Z-170812T2315Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/
Coconino-
229 PM MST SAT AUG 12 2017

...THE FLASH FLOOD WARNING REMAINS IN EFFECT UNTIL 415 PM MST FOR 
ANTELOPE CANYON IN COCONINO COUNTY...

At 224 PM MST, thunderstorms have ended across the warned area. No 
reports of flash flooding have been received yet. However, flash 
flooding will continue to be possible in the slot canyons for the 
next few hours.

Some locations that may experience flooding include...
Antelope Canyon, Antelope Creek Basin, Antelope Canyon Near State 
Road 98.

This includes the following streams and drainages...Antelope Creek...
Kaibito Creek...Sand Wash and Peach Wash.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

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

&&

LAT...LON 3673 11125 3657 11127 3658 11137 3700 11146
      3700 11134

$$

TM

102 
WGUS75 KFGZ 122239
FFSFGZ

Flash Flood Statement
National Weather Service Flagstaff AZ
339 PM MST SAT AUG 12 2017

AZC005-122315-
/O.CON.KFGZ.FF.W.0078.000000T0000Z-170812T2315Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/
Coconino-
339 PM MST SAT AUG 12 2017

...THE FLASH FLOOD WARNING REMAINS IN EFFECT UNTIL 415 PM MST FOR 
ANTELOPE CANYON IN COCONINO COUNTY...

At 337 PM MST, thunderstorms ended across the warned area. No 
reports of flash flooding have been received yet. However, flash 
flooding will continue to be possible in the slot canyons for the 
next hour.

Some locations that may experience flooding include...
Antelope Canyon, Antelope Creek Basin, Antelope Canyon Near State 
Road 98.

This includes the following streams and drainages...Antelope Creek...
Kaibito Creek...Sand Wash and Peach Wash.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

Remain alert for flooding even in locations not receiving rain. Dry
washes, streams, and rivers can become raging killer currents in a
matter of minutes, even from distant rainfall.

&&

LAT...LON 3673 11125 3657 11127 3658 11137 3700 11146
      3700 11134

$$

TM

332 
WGUS75 KFGZ 122316
FFSFGZ

Flash Flood Statement
National Weather Service Flagstaff AZ
416 PM MST SAT AUG 12 2017

AZC005-122326-
/O.EXP.KFGZ.FF.W.0078.000000T0000Z-170812T2315Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/
Coconino-
416 PM MST SAT AUG 12 2017

...THE FLASH FLOOD WARNING FOR ANTELOPE CANYON IN 
COCONINO COUNTY HAS EXPIRED...

The heavy rain has ended. Flooding is no longer expected to pose a
threat. Please continue to monitor weather conditions.

LAT...LON 3673 11125 3657 11127 3658 11137 3700 11146
      3700 11134

$$

TM

Area Forecast Discussion
National Weather Service Flagstaff AZ
948 AM MST Sat Aug 12 2017

.SYNOPSIS...Expect typical monsoon weather conditions through the
weekend. Drier air will bring a decreasing trend in storms
beginning Monday, with mostly dry weather from Tuesday onward.

&&
.DISCUSSION...The KFGZ 12Z sounding showed ample moisture (0.87
PWat) over norther Arizona this morning. Two weak inversions were
noted between 500 and 450 mb. A weak trough, as seen on WV, is
moving through far northern Arizona and Utah this morning. This is
helping to trigger showers and thunderstorms in northwestern
Coconino County already this morning. Updated POPs in this area for
this morning.

&&

.PREV DISCUSSION /413 AM MST/...Low level moisture remains plentiful
across the region this morning with sfc dewpoints in the 50s, though
westerly mid and upper level flow has caused drying aloft. This
setup will continue through the weekend with typical monsoon
thunderstorm coverage during the afternoon and evening, with lower
chances during the overnight hours. The steering flow will push
storms toward the E-NE both today and Sunday. Fairly slow storm
motion will bring a chance of localized heavy rainfall/flooding.
Hail and gusty winds will also accompany the stronger cells.

Monday, continued westerly flow aloft will lead to additional
drying with storm chances falling to the slight chance category
for most areas. By Tuesday, further drying associated with an
upper trough passage should be sufficient to end storm chances for
the majority of northern Arizona with the exception of the White
Mtns region where a slight chance will persist. Breezy southwest
winds are also likely on Monday and Tuesday as the trough moves
through. Dry conditions with near average daytime temperatures
should persist through at least Friday.

&&

.AVIATION...For the 18Z package...A few isolated showers and
thunderstorms are continuing early this morning. More widespread
shower and thunderstorm activity will develop by this afternoon,
with localized MVFR/IFR conditions in the strongest storms. Storm
coverage and intensity will decrease after 03Z Sun. Aviation
discussion not updated for TAF amendments.

&&

.FIRE WEATHER...A moist monsoon air mass will bring an elevated
chance of showers and thunderstorms today and Sunday, with
temperatures slightly below normal.

Monday through Wednesday...A drier air mass is forecast to move back
into the region early next week with decreasing storm chances.
Temperatures will be near to slightly below normal.

&&

.FGZ WATCHES/WARNINGS/ADVISORIES...NONE.

&&

PUBLIC...MAS/JJ
AVIATION...KD
FIRE WEATHER...KD

For Northern Arizona weather information visit
weather.gov/flagstaff

Hazardous Weather Outlook
National Weather Service Flagstaff AZ
426 AM MST Sat Aug 12 2017

AZZ004>018-037>040-130230-
Kaibab Plateau-Marble and Glen Canyons-Grand Canyon Country-
Coconino Plateau-Yavapai County Mountains-
Northeast Plateaus and Mesas Hwy 264 Northward-Chinle Valley-
Chuska Mountains and Defiance Plateau-
Little Colorado River Valley in Coconino County-
Little Colorado River Valley in Navajo County-
Little Colorado River Valley in Apache County-
Western Mogollon Rim-Eastern Mogollon Rim-White Mountains-
Northern Gila County-Yavapai County Valleys and Basins-
Oak Creek and Sycamore Canyons-Black Mesa Area-
Northeast Plateaus and Mesas South of Hwy 264-
426 AM MST Sat Aug 12 2017

This hazardous weather outlook is for Apache...Coconino...
Northern Gila...Navajo...and Yavapai Counties in Northern
Arizona.

.DAY ONE...Today and Tonight

Lingering monsoon moisture will lead to scattered showers and
thundertorms, mainly during the afternoon and evening. Some local
areas could see heavy rain lead to flash flooding, and this will
be the main concern. Small hail and gusty winds are also possible
with stronger cells.

.DAYS TWO THROUGH SEVEN...Sunday through Friday

Expect typical monsoon weather conditions Sunday with scattered
showers and thunderstorms. Thunderstorm threats will include
lightning, heavy rain, and small hail. Drier air will bring
decreasing thunderstorm activity Monday, with little to no chance
of storms Tuesday through Friday.

.SPOTTER INFORMATION STATEMENT...

Weather spotters are encouraged to report significant weather
conditions according to standard operating procedures.