Flash Flood Warning 19, NWS Flagstaff, AZ

Area Forecast Discussion
National Weather Service Flagstaff AZ
342 PM MST Mon Jul 22 2019

.SYNOPSIS...Scattered showers and thunderstorms will continue into
this evening mostly south of I-40. Increasing monsoon moisture
will lead to a more typical monsoonal pattern with daily chances
for showers and thunderstorms across most of northern Arizona through
much of the coming week.

&&

.DISCUSSION...Satellite water vapor imagery shows deep mid and
upper level moisture has moved over northern Arizona. Surface
observations indicate dew points above 50 degrees have pushed up
to the Mogollon Rim and into southern Yavapai County. The high
pressure system has setup over the Four Corners area and models
keep it in place for the next few days. Scattered to numerous
monsoonal thunderstorms have developed over the White Mountains
and the eastern Mogollon Rim producing gusts to 50 mph, heavy rain
and frequent lightning. Isolated thunderstorms are developing
southwest of a line from Holbrook to Grand Canyon Village. High
resolution models keep isolated to scattered showers and
thunderstorms through the evening south of I-40. With more low-
level moisture advecting into northern Arizona over night, Tuesday
will see more wide spread thunderstorms across most of northern
Arizona.

Wednesday and beyond...Monsoon moisture will remain over the
region through the week underneath the subtropical high pressure.
Scattered showers and thunderstorms will develop each day and will
be capable of producing areas of heavy rain and hail. Accompanying
the moisture and showers will also be cooler daytime temperatures.

There are some indications of possible drying Friday or next
weekend, but we would like to see more subsequent model runs
suggesting this before making any big changes to the forecast. For
now in the extended forecast, we will continue with daily chances
for showers and storms favoring the mountainous areas.

&&

.AVIATION...For the 00Z package...Expect VFR conditions across
northern Arizona for the next 24 hours. Isolated, generally high-
based showers and thunderstorms will continue mostly south of
I-40. There is a slight chance of these showers and thunderstorms
continuing overnight. Wind gusts in excess of 45kt are possible
in the vicinity of storms. Otherwise, winds will be southerly at less
than 15 kts through the TAF period. Showers and thunderstorms will
redevelop after 18Z mostly south of the line KGCN-KE91. Aviation
discussion not updated for TAF amendments.

&&

.FIRE WEATHER...The high-based thunderstorms this afternoon will
continue into the evening south of I-40. These storms will
produce strong outflow winds and heavy rain. Tuesday and Wednesday,
deeper moisture arrives with the thunderstorm coverage increasing
to most of northern Arizona. The potential for strong outflow
winds will persist, but the chance for wetting rain and flash
flooding over sensitive areas, such as burn scars, increases.

Thursday through Saturday...Active monsoon weather will continue
with afternoon and evening showers and thunderstorms.

&&

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

&&

PUBLIC SHORT/LONG TERM FCSTR...DB/MCT
AVIATION...DB
FIRE WEATHER...DB

For Northern Arizona weather information visit
weather.gov/flagstaff

Special Weather Statement
National Weather Service Flagstaff AZ
244 PM MST Mon Jul 22 2019

AZZ016>018-222230-
Northern Gila County-White Mountains-Eastern Mogollon Rim-
244 PM MST Mon Jul 22 2019

...SIGNIFICANT WEATHER ADVISORY FOR GILA AND NAVAJO COUNTIES UNTIL
330 PM MST...

At 243 PM MST, Doppler radar was tracking a strong thunderstorm near
Carrizo, moving southwest at 15 mph.

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

Locations impacted include...
Fort Apache Reservation, Carrizo and Cedar Creek.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

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 3381 11028 3399 11043 3406 11018 3393 11008
TIME...MOT...LOC 2143Z 060DEG 13KT 3397 11022

McCollum

Special Weather Statement
National Weather Service Flagstaff AZ
333 PM MST Mon Jul 22 2019

AZZ016-018-222300-
Northern Gila County-Eastern Mogollon Rim-
333 PM MST Mon Jul 22 2019

...STRONG THUNDERSTORMS FROM FOREST LAKES TO 15 MILES SOUTH
OF HEBER...

At 329 PM MST, Doppler radar was tracking an area of strong
thunderstorms from Forest Lakes to 15 miles south of Heber. This
storm was nearly stationary.

Pea size hail and winds in excess of 30 mph will be possible with
this storm.

Locations impacted include...
Forest Lakes, Canyon Creek Fish Hatchery, Gentry Campground, Canyon
Point Campground, Black Canyon Rim Campground and Airplane Flat
Campground.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

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 3425 11047 3419 11049 3425 11085 3436 11081
TIME...MOT...LOC 2229Z 100DEG 3KT 3424 11054

McCollum