Severe Thunderstorm Warning 221, NWS Amarillo, TX

769 
WWUS54 KAMA 101727
SVSAMA

Severe Weather Statement
National Weather Service Amarillo TX
1227 PM CDT THU AUG 10 2017

OKC007-139-101815-
/O.CON.KAMA.SV.W.0221.000000T0000Z-170810T1815Z/
Beaver OK-Texas OK-
1227 PM CDT THU AUG 10 2017

...A SEVERE THUNDERSTORM WARNING REMAINS IN EFFECT UNTIL 115 PM CDT
FOR WESTERN BEAVER AND NORTHEASTERN TEXAS COUNTIES...

At 1227 PM CDT, a severe thunderstorm was located 5 miles south of
Hayne, moving east at 35 mph.

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

SOURCE...Radar indicated. 

IMPACT...Minor damage to roofs, siding, and trees is possible. Hail 
         damage to vehicles is expected. 

Locations impacted include...
Beaver, Forgan, Mocane, Turpin and Floris. 

PRECAUTIONARY/PREPAREDNESS ACTIONS...

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

To report severe weather contact your nearest law enforcement agency.
They will send your report to the National Weather Service office in
Amarillo.

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

&&

LAT...LON 3660 10060 3700 10107 3700 10037
TIME...MOT...LOC 1727Z 290DEG 29KT 3702 10079 

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

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305 
WWUS54 KAMA 101736
SVSAMA

Severe Weather Statement
National Weather Service Amarillo TX
1236 PM CDT THU AUG 10 2017

OKC007-139-101746-
/O.CAN.KAMA.SV.W.0221.000000T0000Z-170810T1815Z/
Beaver OK-Texas OK-
1236 PM CDT THU AUG 10 2017

...THE SEVERE THUNDERSTORM WARNING FOR WESTERN BEAVER AND
NORTHEASTERN TEXAS COUNTIES IS CANCELLED...
                
The storm which prompted the warning has weakened below severe
limits, and no longer poses an immediate threat to life or property.
Therefore the warning has been cancelled.

LAT...LON 3660 10060 3700 10107 3700 10037
TIME...MOT...LOC 1735Z 290DEG 29KT 3699 10070 

$$

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Area Forecast Discussion...UPDATED
National Weather Service Amarillo TX
702 AM CDT Thu Aug 10 2017

.AVIATION...
For the 12Z TAFs, latest round of showers and tstms should be east
of the TAF sites by around 14Z this morning, and have reflected
this in the fcst. Expect a lull in the precipitation by around mid
morning through much of the afternoon hours. Then another crop of
showers and tstms is forecast to develop late this afternoon
through the evening and nighttime hours, with the greatest threat
at KGUY and KDHT, and have included PROB30 groups at those sites
for later this evening and tonight. Low confidence in storms
affecting KAMA during this same time period precludes mentioning
for this fcst issuance. Finally, a weak cold front will move
slowly south across the terminal sites later this evening and
tonight.

Andrade

&&

.PREV DISCUSSION... /Issued 409 AM CDT Thu Aug 10 2017/

DISCUSSION...
Northwest flow bringing daily rain/thunderstorm chances continues
to dominate the overall weather pattern over the TX/OK
Panhandles. This is primarily due to anti-cyclonic flow over the
Sonoran Desert and persistent cyclonic flow over the Great Lakes
region extending over the eastern CONUS. This upper level pattern
is not expected to change much over the next 7 days.

As of 08z, an area of elevated showers and thunderstorms were
moving southeast over Hartley and Dallam Counties in responce to a
shortwave in the northwest flow and decent 700mb theta-E
advection. One storm has shown signs of being strong. With MUCAPE
around 1500 J/kg and 0-6km effective bulk shear values around 25
knots certainly can't rule out some strong wind (but would have to
punch through any surface inversion). Severe hail seems unlikely
given warm 500mb temps around -4 deg C. Heavy rain will be the
main concern given previous rains and plentiful moisture
throughout most of the vertical profile. These storms should move
into the Amarillo area over the next hour or so and may produce
around 0.5" to 1.5" for areas that see the heavier rainfall.
Coverage of showers and storms should be on the decrease after 12z
with a few lingering storms mainly in the Texas Panhandle. There
may then be a lull in activity for Thursday afternoon before the
next system moves into the area. High temperatures should get
right around normal with low 90s across most of the area.

The next round of showers and thunderstorms are expected to
develop in responce to another northwest flow shortwave and move
into the northwestern zones Thursday evening. Deterministic model
guidance is also indicating that a frontal boundary will be
approaching the northern zones around the same time, with
additional thunderstorm development along the boundary.
Probablistic guidance suggest the highest rain chances will be
across the Oklahoma Panhandle and northern Texas Panhandle between
06z and 12z Friday. However, this may shift south some depending
on how far south the front is able to advance. The NAM is very
aggressive with the front, pushing it all the way through the
Panhandles by 12z Friday. Effective shear near the front may
approach 40 knots during the evening along with MLCAPE around
1000-2000 J/kg, so a strong to marginally severe storm is not out
of question. The main threat with storms will continue to be heavy
rain and flooding/flash flooding with PWATs above the 90th
percentile and saturated soils from rains over the last week.
Depending on better confidence in overall storm mode and storm
motion, may need to consider flood/flash flood watch for some
northern zones on Thursday night and Friday morning.

The position of the front will have a large effect on
temperatures and potential thunderstorm development Friday. For
now going with blend. Beyond Friday, overall pattern remains the
same. Northwest flow aloft with nearly daily shortwaves moving
through flow bringing nocturnal convection. Another decent wave is
already showing up in the model guidance for late Friday night
into early Saturday. Moisture values will remain well above
average, with PWATs around 1.3-1.7 inches each day and surface
dewpoints staying around 60-65 deg F. Temperatures should be right
around average with highs in the upper 80s and lowers 90s.

Ward

&&

.AMA Watches/Warnings/Advisories...
TX...None.
OK...None.

&&

Hazardous Weather Outlook...UPDATED
National Weather Service Amarillo TX
1211 PM CDT Thu Aug 10 2017

OKZ001>003-TXZ001>020-110515-
Cimarron-Texas-Beaver-Dallam-Sherman-Hansford-Ochiltree-Lipscomb-
Hartley-Moore-Hutchinson-Roberts-Hemphill-Oldham-Potter-Carson-
Gray-Wheeler-Deaf Smith-Randall-Armstrong-Donley-Collingsworth-
1211 PM CDT Thu Aug 10 2017

This Hazardous Weather Outlook is for the Texas and Oklahoma
Panhandles.

.DAY ONE...This Afternoon and Tonight.

Thunderstorms will be possible across the panhandles through
tonight. Some storms may become severe mainly across the Oklahoma
Panhandle the northern Texas Panhandle, with damaging winds and large
hail the primary hazards. Another concern will be heavy rainfall,
which may lead to localized flooding or flash flooding.

.DAYS TWO THROUGH SEVEN...Friday through Wednesday.

Thunderstorms will be possible across the Oklahoma and Texas
Panhandles every day through mid next week. Some storms that
develop during this time period may become strong to marginally
severe, with strong wind gusts and hail the primary hazards. In
addition, the strongest storms will be capable of producing heavy
rainfall, which may lead to localized flooding or flash flooding.

.SPOTTER INFORMATION STATEMENT...

Spotter groups and emergency management agencies should be ready
for possible activation this afternoon and tonight.

PRELIMINARY LOCAL STORM REPORT
NATIONAL WEATHER SERVICE AMARILLO TX
810 AM CDT THU AUG 10 2017

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

0806 AM     FLASH FLOOD      2 SSW WASHBURN          35.15N 101.59W
08/10/2017                   ARMSTRONG          TX   LAW ENFORCEMENT

            FLOODING HAS BEEN REPORTED ON COUNTY ROAD 2 AND FM
            1151.

&&

EVENT NUMBER AMA1700804

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PRELIMINARY LOCAL STORM REPORT
NATIONAL WEATHER SERVICE AMARILLO TX
822 AM CDT THU AUG 10 2017

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

0819 AM     FLASH FLOOD      6 SW AMARILLO           35.15N 101.89W
08/10/2017                   RANDALL            TX   NWS EMPLOYEE

            INTERSTATE 27 CLOSED WITH TRAFFIC BEING DIVERTED TO THE
            ACCESS ROADS. FLOODING HAS ALSO BEEN REPORTED IN LOW
            SPOTS ON INTERSTATE 40 THROUGH TOWN AS WELL AS MOST
            UNDERPASSES IN DOWNTOWN AMARILLO.

&&

EVENT NUMBER AMA1700805

14