Tornado Watch 155

Issued

Apr 21, 2017, 4:40 PM CDT (21:40 UTC)

Expired

Apr 22, 2017, 1:00 AM CDT

In force

8 hr

Issued by

the Storm Prediction Center

Largest hail expected

2 in

Strongest gust expected

60 kt

The Western Arkansas radar (KSRX), 197 km from the middle of the area, began a volume at 21:40 UTC, the scan nearest the moment this went out.

Open the radar archive at this moment

The archived warnings, watches and discussions in force at that minute are drawn over the scan, this one among them.

Two or more tornadoes

50%

One or more EF2 to EF5 tornadoes

20%

Ten or more severe wind reports

40%

One or more gusts of 65 knots or more

20%

Ten or more severe hail reports

40%

One or more hailstones of 2 inches or more

30%

Six or more combined severe hail and wind reports

70%

• Mesoscale Discussion 536Apr 21, 1:12 PM CDT
• Mesoscale Discussion 538Apr 21, 3:09 PM CDT
• Mesoscale Discussion 540Apr 21, 3:54 PM CDT
• Mesoscale Discussion 541Apr 21, 7:11 PM CDT
• Mesoscale Discussion 542Apr 21, 9:28 PM CDT
• Mesoscale Discussion 543Apr 21, 11:39 PM CDT

459 
WWUS20 KWNS 212138
SEL5  
SPC WW 212138
ARZ000-OKZ000-TXZ000-220600-

URGENT - IMMEDIATE BROADCAST REQUESTED
Tornado Watch Number 155
NWS Storm Prediction Center Norman OK
440 PM CDT Fri Apr 21 2017

The NWS Storm Prediction Center has issued a

* Tornado Watch for portions of 
  western Arkansas
  southeast Oklahoma
  north centrtal and northeast Texas

* Effective this Friday afternoon and Saturday morning from 440
  PM until 100 AM CDT.

* Primary threats include...
  A few tornadoes possible
  Scattered large hail and isolated very large hail events to 2
    inches in diameter possible
  Scattered damaging wind gusts to 70 mph possible

SUMMARY...A few supercells are expected to develop in vicinity of a
cold front and convectively reinforced boundary, and some storms may
evolve into line segments. Large hail, damaging wind and a few
tornadoes will be possible with this activity this evening.

The tornado watch area is approximately along and 110 statute miles
east and west of a line from 20 miles east northeast of Poteau OK to
45 miles south southeast of Fort Worth TX. For a complete depiction
of the watch see the associated watch outline update (WOUS64 KWNS
WOU5).

PRECAUTIONARY/PREPAREDNESS ACTIONS...

REMEMBER...A Tornado Watch means conditions are favorable for
tornadoes and severe thunderstorms in and close to the watch
area. Persons in these areas should be on the lookout for
threatening weather conditions and listen for later statements
and possible warnings.

&&

AVIATION...Tornadoes and a few severe thunderstorms with hail
surface and aloft to 2 inches. Extreme turbulence and surface wind
gusts to 60 knots. A few cumulonimbi with maximum tops to 500. Mean
storm motion vector 26035.

...Dial

Tornado Watches in Texas, 2017Tornado Watches in Oklahoma, 2017Tornado Watches in Arkansas, 2017Every tornado watch in 2017

The product and its follow-ups from the Iowa Environmental Mesonet's archive of National Weather Service and Storm Prediction Center text; the sounding from the Mesonet's radiosonde archive; radar from the NEXRAD Level II archive.