Flash Flood Warning 7, NWS Las Vegas, NV

412 
WGUS75 KVEF 240507
FFSVEF

Flash Flood Statement
National Weather Service Las Vegas NV
1007 PM PDT Thu Jul 23 2020

AZC015-240715-
/O.CON.KVEF.FF.W.0007.000000T0000Z-200724T0715Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/
Mohave AZ-
1007 PM MST Thu Jul 23 2020

...FLASH FLOOD WARNING REMAINS IN EFFECT UNTIL 1215 AM MST FRIDAY 
FOR SOUTHERN MOHAVE COUNTY...

At 1005 PM MST, The first round of thunderstorms had moved away and 
weakened, but another storm was moving over Wikieup. This could add 
more water to the Big Sandy River, possibly flooding secondary roads 
such as Signal Road.

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

SOURCE...Doppler radar and automated gauges.

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

Some locations that will experience flash flooding include...
  mainly rural areas of Southern Mohave County

Big Sandy River south of Wikieup.

This includes the following streams and drainages...
  Santa Maria River, Graveyard Wash, Box Canyon Wash, Government 
  Wash, Bill Williams River, Burro Creek, Big Sandy River and Rupley 
  Wash.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

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

Excessive runoff from heavy rainfall will cause flooding of small 
creeks and streams, country roads, farmland, and other low lying 
spots.

&&

LAT...LON 3466 11359 3461 11354 3430 11350 3430 11351
      3431 11351 3431 11352 3431 11353 3431 11355
      3446 11365 3447 11365

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

$$

CM

399 
WGUS75 KVEF 240601
FFSVEF

Flash Flood Statement
National Weather Service Las Vegas NV
1101 PM PDT Thu Jul 23 2020

AZC015-240715-
/O.CON.KVEF.FF.W.0007.000000T0000Z-200724T0715Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/
Mohave AZ-
1101 PM MST Thu Jul 23 2020

...FLASH FLOOD WARNING REMAINS IN EFFECT UNTIL 1215 AM MST FRIDAY 
FOR SOUTHERN MOHAVE COUNTY...

At 1100 PM MST, thunderstorms with heavy rain had moved away from 
the Big Sandy River. However, water is likely still flowing down the 
river from earlier heavy rain.

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

SOURCE...Doppler radar and automated gauges.

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

Some locations that will experience flash flooding include...
  secondary roads which cross the Big Sandy River south of Wikieup

This includes the following streams and drainages...
  Santa Maria River, Graveyard Wash, Box Canyon Wash, Government 
  Wash, Bill Williams River, Burro Creek, Big Sandy River and Rupley 
  Wash.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

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

Excessive runoff from heavy rainfall will cause flooding of small 
creeks and streams, country roads, farmland, and other low lying 
spots.

&&

LAT...LON 3466 11359 3461 11354 3430 11350 3430 11351
      3431 11351 3431 11352 3431 11353 3431 11355
      3446 11365 3447 11365

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

$$

CM

503 
WGUS75 KVEF 240709
FFSVEF

Flash Flood Statement
National Weather Service Las Vegas NV
1209 AM PDT Fri Jul 24 2020

AZC015-240719-
/O.EXP.KVEF.FF.W.0007.000000T0000Z-200724T0715Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/
Mohave AZ-
1209 AM MST Fri Jul 24 2020

...FLASH FLOOD WARNING WILL EXPIRE AT 1215 AM MST EARLY THIS MORNING 
FOR SOUTHERN MOHAVE COUNTY...

Heavy rain has ended, so no new flooding is expected. However, water 
may still be flowing down the Big Sandy River, which could flood 
secondary roads such as Signal Road. Please continue to heed any 
road closures.

LAT...LON 3466 11359 3461 11354 3430 11350 3430 11351
      3431 11351 3431 11352 3431 11353 3431 11355
      3446 11365 3447 11365

$$

CM

Area Forecast Discussion
National Weather Service Las Vegas NV
800 PM PDT Thu Jul 23 2020

.SYNOPSIS...Scattered thunderstorms with gusty outflow winds are
likely across northwest Arizona today but are also possible across
portions of Lincoln County. Thunderstorm chances will linger in
northwest Arizona through Friday. Seasonably cool temperatures,
breezy winds are expected areawide through the weekend. An uptick in
monsoon moisture will be possible next week.
&&

.UPDATE...Winds were settling down as expected over Lincoln County,
so the Red Flag Warning will be allowed to expire. Thunderstorms
over Mohave County had been few and far between thus far, and were
still ongoing mainly east of Kingman. Forecast captures the trends
well thus far, so no update planned at this time, but will continue
to monitor in case thunderstorm chances need to be ended more
quickly.
&&

.AVIATION...For McCarran...Southwest winds generally at or below
10 knots overnight then light and variable after sunrise. Winds
Friday afternoon are expected to be easterly and primarily below 10
kts. Thunderstorms are possible in the Peach Springs corridor and
near the Mormon Mesa corridor Friday afternoon. Light winds expected
by tomorrow morning. FEW clouds aoa 10K ft Friday afternoon.

For the rest of southern Nevada, northwest Arizona and southeast
California...Typical drainage winds overnight with a southerly
component generally under 15 kts Friday afternoon. FEW to SCT clouds
aoa 10K ft.
&&

.PREV DISCUSSION...
1218 PM PDT Thu Jul 23 2020

.SHORT TERM...through Sunday.

Per the visual from mid-level water vapor, the closed low is now
opening as it moves across central California. As expected,
convective initiation is already occurring across Mohave County,
while convective initiation attempts are happening across the
southeastern half of Lincoln County.

Instability continues to increase across those areas amid sufficient
low-level moisture and steepened mid-level lapse rates (thanks to
the mid-level wave and associated speed maxima). There will be
sufficient shear across northern Mohave County this afternoon and
evening, allowing for deeper, slightly organized convection there.
The main concern with any convection through the afternoon and
evening will be gusty outflow from nearby or distant thunderstorms.
With isolated storms gusts up to 50 MPH are possible, but generally
are expected to be 30-40 MPH. Tonight there remains the possibility
of nighttime convection in Mohave County as an outflow shoots
westward, possibly continuing convection for 2-4 hours after sunset.
Though steering flow is relatively strong, slow moving convection
along developing cold pools may result in very isolated flooding,
specifically for southern Mohave County this evening.

In addition to the thunderstorms today, breezy to locally gusty
winds are still expected across portions of the southern Great Basin
this afternoon, elevating fire danger. That said, the Red Flag has
been left as is - ending 8 PM tonight.

As the weakening shortwave pivots northeastward Friday winds will be
reduced and breezy at best during the afternoon. Without extra
convective support from the mid-level wave, convection across
northwest Arizona on Friday is expected to be diurnal and favor the
terrain for the most part. All other areas may see some cu buildups,
but convection is unlikely on Friday.

Weak cyclonic flow aloft will persist through the weekend, allowing
dry conditions to continue for the region. There still may be
isolated, terrain-driven storms in northwest Arizona through the
weekend.

Seasonably "cool", by late-July standards, conditions are expected
to last through the weekend.

.LONG TERM...Monday through next Thursday.

By early next week there is a signal from ensembles that the typical
monsoon ridge will become situated near the Four Corners,
potentially priming the pump for a moisture surge Additionally
Tropical Depression #8 may be a key factor in a surge of moderate to
high-grade moisture by Wednesday or Thursday next week. Taking this
with a grain of salt at the moment, but the potential for a decent
period of thunderstorms and attending threats is increasing.

Also, with the subtropical ridge developing, temps will increase
above average once again next week.
&&

.FIRE WEATHER...Today will be the last day of critical winds across
the Great Basin. Tomorrow (Friday) breezy winds are expected but
will be substantially weaker. Scattered thunderstorms possible this
afternoon and Friday in northwest Arizona> More isolated
thunderstorms are possible for Lincoln county this afternoon. A
period of generally dry weather expected over the weekend, with
potential for increasing monsoon moisture next week along with
increasing temperatures.
&&

.AVIATION...For McCarran...Southerly winds are expected to continue
through the day today across the region with afternoon gusts
generally 20 to 25 knots. Southerly winds will decrease by 02-03Z
this evening, generally remaining below 10 knots. Scattered
thunderstorms expected in the Peach Springs and near the Mormon Mesa
corridors this afternoon/evening. Light winds expected by tomorrow
morning. Some FEW to SCT aoa 10 Kft possible this afternoon.

For the rest of southern Nevada, northwest Arizona and southeast
California...Southerly winds will continue across the region today
with gusts generally 20 to 25 knots. Scattered showers and
thunderstorms are expected to mostly stay away from terminals today
and remain across northwest AZ and far eastern southern NV. Gusty
outflows are expected with any storms that develop but should remain
across northwest AZ. Typical drainage winds will resume between 03-
04Z later this evening. Expect periods of clouds FEW to SCT aoa 10
Kft.
&&

.SPOTTER INFORMATION STATEMENT...Spotters are encouraged to report
any significant weather or impacts according to standard operating
procedures.
&&

UPDATE...Morgan
AVIATION...Salmen
DISCUSSION/FIRE WEATHER...Boothe
AVIATION...Kryston

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