Flash Flood Warning 37, NWS Tucson, AZ

609 
WGUS75 KTWC 030318
FFSTWC

Flash Flood Statement
National Weather Service Tucson AZ
818 PM MST TUE OCT 2 2018

AZC019-030715-
/O.CON.KTWC.FF.W.0037.000000T0000Z-181003T0715Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/
Pima-
818 PM MST TUE OCT 2 2018

...THE FLASH FLOOD WARNING REMAINS IN EFFECT UNTIL 1215 AM MST FOR 
IMMINENT MENAGERS LAKE DAM FAILURE ON THE TOHONO O'ODHAM NATION IN 
CENTRAL PIMA COUNTY...

At 815 PM MST, emergency management continued to report rising water 
in Menagers Lake with the lake level within one foot of overtopping 
the dam. If the dam is overtopped, which appears likely, the dam 
could give way resulting in rapid flash flooding of the town of Ali 
Chuk and surrounding area as the flood waters rush toward the 
Mexican border. Flash flooding is expected to begin shortly and 
immediate evacuation of the Ali Chuk area is strongly advised per 
Tohono O'odham Nation authorities.

* Some locations that will experience flooding include...
  Ali Chuk.

Some locations that will experience flooding include...
Ali Chuk.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

Move to higher ground now. This is an extremely dangerous and
life-threatening situation. Do not attempt to travel unless you are
fleeing an area subject to flooding or under an evacuation order.

Stay away or be swept away. River banks and culverts can become
unstable and unsafe.

&&

LAT...LON 3183 11265 3189 11252 3177 11244

$$

GL

048 
WGUS55 KTWC 030711
FFWTWC
AZC019-031315-
/O.EXT.KTWC.FF.W.0037.000000T0000Z-181003T1315Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/

BULLETIN - EAS ACTIVATION REQUESTED
Flash Flood Warning
National Weather Service Tucson AZ
1211 AM MST WED OCT 3 2018

The National Weather Service in Tucson has extended the

* Flash Flood Warning for...
  Central Pima County in southeastern Arizona...

* Until 615 AM MST Wednesday.

* At 1206 AM MST, no new information has been received by this 
  office with respects to rising water in Menagers Lake with the 
  lake level within one foot of overtopping the dam Monday night. If 
  the dam is overtopped, which appears likely, the dam could give 
  way resulting in rapid flash flooding of the town of Ali Chuk and 
  surrounding area as the flood waters rush toward the Mexican 
  border.

* Some locations that will experience flooding include...
  Ali Chuk.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

Move to higher ground now. This is an extremely dangerous and life-
threatening situation. Do not attempt to travel unless you are 
fleeing an area subject to flooding or under an evacuation order.

Stay away or be swept away. River banks and culverts can become
unstable and unsafe.

&&

LAT...LON 3183 11265 3189 11252 3177 11244

$$

Area Forecast Discussion
National Weather Service Tucson AZ
306 PM MST Tue Oct 2 2018

.SYNOPSIS...Areas of showers with isolated thunderstorms will
continue overnight. Isolated showers and thunderstorms Wednesday,
then mainly dry conditions Thursday into Saturday. A chance of
showers and thunderstorms returns early next week with strong
gusty winds as a cool weather system pushes in from the northwest.

&&

.DISCUSSION...Shearing remains of the bulk of Rosa's moisture and
energy northwest and north of Tucson this afternoon, with areas
of light to moderate showers still spreading across the area from
the west and south. The heaviest rainfall has ended for most of
our area, however we will be watching some areas of potential
enhancement this evening and overnight mainly north of Tucson.
Rainfall will be spottier over areas that saw flooding rains
across large areas of the Tohono O'Odham Nation (mainly west and
north of Sells). Please see the Hydrology section below for
details about that area.

We could see some patchy fog overnight in the hardest hit areas,
primarily west of Tucson. Some residual boundary layer moisture
will combine with dynamics from a trough approaching from the west
for a few thunderstorms near the mountains Wednesday afternoon and
evening. Weak troughiness with a nearly zonal flow should keep
temperatures from pushing back above average later in the week.

We're seeing good operational and ensemble mean agreement about a
strong and deep trough digging into the region this weekend.
Stacked isoheights straight from Alaska, so it should be a true
fall-like transition season storm complete with blustery winds and
temperatures 15 degrees below average by Sunday or Monday. A
hybrid track that will probably have some moisture to work with
even this far south. We might actually be forecasting meaningful
snow levels to start the new week, with a chance of snow at
highest elevations, say above 8k feet or so.

&&

.AVIATION...Valid through 04/00Z.
Areas of -SHRA and isolated -TSRA overnight. Expect MVFR
conditions or brief IFR with heavier rainfall. Otherwise, cloud
decks around 6k-8k ft AGL. Patchy fog possible overnight. SFC
wind 12-17 kts out of the south and southwest with gusts near 25
kts, diminishing overnight with normal diurnal trends tomorrow.
Aviation discussion not updated for TAF amendments.

&&

.FIRE WEATHER...Areas of showers and isolated thunderstorms will
occur through tonight, with the highest rainfall chances north of
Tucson. Isolated showers and thunderstorms will then persist into
Thursday. Dry conditions are expected across much of the area
Friday and Saturday. A chance of showers and thunderstorms returns
Sunday into Monday mainly from Tucson eastward. Gusty south winds
will occur today, with gusty southwest winds late in the upcoming
weekend and early next week. Otherwise, 20-foot winds will be
terrain driven mainly less than 15 mph.

&&

.HYDROLOGY...Flood Warnings for portions of the Tohono O'Odham
Nation continue, mainly in the districts west and north of
Sells. Additional rainfall will be much spottier but heavy flow
and flooding will continue from earlier amounts between 3 and 4
inches. Latest stage from the Vamori Wash was down to 9.9 feet
from a high this morning of just over 10 feet. That translates to
a flow of about 1300 cfs near Kom Vo.

&&

.TWC WATCHES/WARNINGS/ADVISORIES...
Flash Flood Watch through late tonight for AZZ501-502-505-506.

&&

Meyer/Hardin/Howlett

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