Alert archive / Oklahoma / Tornado Watches in 2016

Tornado Watch 41

March 13, 201616 counties in Oklahoma

The Storm Prediction Center issued this tornado watch at Mar 13, 2016, 12:57 PM CDT for 16 counties in Oklahoma. It was in force for 6 hr.

The area

The outline as issued.

The facts

Issued
Mar 13, 2016, 12:57 PM CDT (17:57 UTC)
Expired
Mar 13, 2016, 7:00 PM CDT
In force
6 hr
Issued by
the Storm Prediction Center
Largest hail expected
2 in
Strongest gust expected
60 kt

Counties Atoka County, OK, Coal County, OK, Haskell County, OK, Hughes County, OK, Latimer County, OK, LeFlore County, OK, McIntosh County, OK, Muskogee County, OK, Okfuskee County, OK, Okmulgee County, OK, Pittsburg County, OK, Pontotoc County, OK, Pottawatomie County, OK, Pushmataha County, OK, Seminole County, OK, Sequoyah County, OK

The radar

The Tulsa radar (KINX), 113 km from the middle of the area, began a volume at 17:58 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.

What SPC expected

The probabilities SPC published with the watch, for the watch area over its life.

Two or more tornadoes
50%
One or more EF2 to EF5 tornadoes
20%
Ten or more severe wind reports
30%
One or more gusts of 65 knots or more
10%
Ten or more severe hail reports
60%
One or more hailstones of 2 inches or more
30%
Six or more combined severe hail and wind reports
70%

Warnings issued inside it

4 tornado, severe thunderstorm and flash flood warnings for its counties while it was in force.

IssuedProductOfficeCountiesLasted
Mar 13, 2:59 PM CDTSevere Thunderstorm WarningTSALeFlore31 min
Mar 13, 3:27 PM CDTSevere Thunderstorm WarningTSALeFlore33 min
Mar 13, 3:42 PM CDTSevere Thunderstorm WarningTSAHaskell, LeFlore33 min
Mar 13, 4:14 PM CDTSevere Thunderstorm WarningTSAHaskell31 min

Discussions around it

SPC mesoscale discussions over the same counties from four hours before the watch to its end.

The nearest sounding before it

Norman, OK (KOUN), launched 12:00Z, 6.0 hours before the alert went out and 147 km from the middle of its area. This is the routine balloon launch nearest before it, the air the forecaster had in hand, not a measurement taken for the alert.

Skew-T log-pSkew-T log-p diagram, Norman, OK at 12:00Z on 2016-03-13Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 103 joules per kilogram.LCLLFCEL10008507005003002001001 km2 km3 km6 km9 km12 km15 km-30°-20°-10°10°20°30°40°
Temperature in red, dew point in green, the mixed-layer parcel dashed.
HodographHodograph, Norman, OK at 12:00Z on 2016-03-13The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity 143 square meters per square second.19395878Sfc1 km3 km6 km9 kmRMLM
The wind turning with height, colored by layer: ground to 1 km, 1 to 3 km, 3 to 6 km, 6 to 10 km.
Mixed-layer CAPE
103 J/kg
Mixed-layer CIN
-278 J/kg
Mixed-layer LCL
1061 m above ground
0-6 km bulk shear
49 kt
0-1 km storm-relative helicity
143 m²/s²
0-3 km storm-relative helicity
155 m²/s²
Significant tornado parameter
0.0
Supercell composite
0.0

Open this sounding in Storm Lab

The text

As transmitted.

517 
WWUS20 KWNS 131754
SEL1  
SPC WW 131754
ARZ000-OKZ000-140000-

URGENT - IMMEDIATE BROADCAST REQUESTED
TORNADO WATCH NUMBER 41
NWS STORM PREDICTION CENTER NORMAN OK
100 PM CDT SUN MAR 13 2016

THE NWS STORM PREDICTION CENTER HAS ISSUED A

* TORNADO WATCH FOR PORTIONS OF 
  WEST CENTRAL ARKANSAS
  SOUTHEAST OKLAHOMA

* EFFECTIVE THIS SUNDAY AFTERNOON AND EVENING FROM 100 PM UNTIL
  700 PM CDT.

* PRIMARY THREATS INCLUDE...
  A FEW TORNADOES POSSIBLE
  SCATTERED LARGE HAIL LIKELY WITH ISOLATED VERY LARGE HAIL EVENTS
    TO 2 INCHES IN DIAMETER POSSIBLE
  ISOLATED DAMAGING WIND GUSTS TO 70 MPH POSSIBLE

SUMMARY...THUNDERSTORMS ARE BEGINNING TO FORM OVER SOUTHEAST OK
ALONG A WARM FRONT.  THESE STORMS WILL POSE A RISK OF LARGE HAIL AND
ISOLATED TORNADOES THIS AFTERNOON ACROSS THE WATCH AREA.

THE TORNADO WATCH AREA IS APPROXIMATELY ALONG AND 40 STATUTE
MILES NORTH AND SOUTH OF A LINE FROM 55 MILES WEST NORTHWEST OF
MCALESTER OKLAHOMA TO 15 MILES SOUTHEAST OF POTEAU OKLAHOMA.  FOR
A COMPLETE DEPICTION OF THE WATCH SEE THE ASSOCIATED WATCH
OUTLINE UPDATE (WOUS64 KWNS WOU1).

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 24030.


...HART

SPC that day

Everything else SPC issued on the same UTC day.

IssuedProductOfficeCountiesLasted
Mar 13, 12:35 PM CDTMesoscale DiscussionSPCCoal, Haskell, Latimer, LeFlore, McCurtain, Pittsburg and 1 more55 min
Mar 13, 2:10 PM CDTTornado WatchSPCMcCurtain5 hr
Mar 13, 3:19 PM CDTMesoscale DiscussionSPCCoal, Haskell, Hughes, Latimer, LeFlore, McIntosh and 4 more86 min
Mar 13, 5:35 PM CDTMesoscale DiscussionSPCAdair, Cherokee, Delaware, Haskell, LeFlore, Mayes and 6 more85 min
Mar 13, 5:58 PM CDTMesoscale DiscussionSPCMcCurtain92 min

Nearby

Tornado Watches in Oklahoma, 2016Every tornado watch in 2016

Sources

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.