Chase Report: 24 May, 2011 - Goldsby, OK EF4

EF4 Tornado near Washington, OK - ~5:55 CDT

High risk for Central and Northern OK. The associated Tornado prob from the 1630Z outlook shown below, with huge 45% hatched contour.

Solo chase. My forecasted target was around the OK/KS border, Alva, OK to Medicine Lodge, KS. Fortunately, I was working all morning and did not get out of the driveway until about 12:30 p.m. While there was action at the Northern target, Central OK ended up being the breeding ground for the strongest tornadoes of the day. Stopped just north of Fort Worth at the I-35/287 junction around 3:15 CDT. Severe cells were in progress to my west within a couple of counties. Broken line of supercells had fired on the dryline W and NW of OK City. Made a quick decision to shoot north and try to get to the southern end of the Central OK storms. Within a few minutes of that decision, three of the Central OK storms went tornado-warned.

Made good time moving up 35, but cell motion was NNE at the time, and fast- 45-55 knots (I think). Around 4 p.m., crossed the Red River. The most damaging tornado of the day was already in progress. It would go through El Reno and Guthrie over its 75 mile track, and cause 9 fatalities. This tornado has been rated EF-5 based on radar data collected by a mobile radar.

As I approached Purcell, OK, a new cell that had formed south of the original OK line went tornado-warned near Bradley. I had no data for a long stretch about this time. Got some much needed help from chasing partner John S, who was unable to go with me on the trip. There were two cells within range, both with tornado warnings. The northern cell produced an EF4 from Chickasha to Moore, and at the time had a better radar presentation. However, I did not think I could get up to it in time, and the hail core from the southern cell was already over I-35. I decided to pull off and try to get the Bradley tornado.

Took exit 101 (Ladd Rd), and pretty quickly had a visual on the southern edge of the rain free base. Contrast was poor and I was taking some small hail with an occasional larger stone. Moved slightly west to Pacer Field, and about 5:52, a tall stovepipe tornado in progress came into view to my Southwest.

I reported the tornado and observed it for several minutes as it got closer. Initially thought it would track over my location, but it ended up turning north towards the end of its life cycle according to the current survey details (survey not yet finalized). That is consistent with what I observed.

While observing this tornado, a new lowering formed to my immediate west. It quickly began to produce a funnel cloud and shortly after that, at around 5:58, it kicked up a debris cloud within 100 yards of my location.

While it did not look to be a very strong tornado, I had to relocate quickly to avoid getting hit. The new tornado went past me- technically, I was probably in the outer edge of the circulation- but it remained weak and dissipated once it crossed I-35. The main tornado was roping out by this stage, and completely dissipated shortly after 6 p.m.

Here is the preliminary NWS survey of the Goldsby tornao:

STORM 4... WASHINGTON-GOLDSBY
PRELIMINARY DATA...
EVENT DATE: MAY 24, 2011
EVENT TYPE: TORNADO
EF RATING: EF-4
ESTIMATED PEAK WINDS (MPH): 190
INJURIES/FATALITIES: UNKNOWN/NONE
EVENT START LOCATION AND TIME: 4 SW BRADLEY 5:26 PM CDT
EVENT END LOCATION AND TIME: 1 NW GOLDSBY 6:05 PM CDT
DAMAGE PATH LENGTH (IN MILES): 27 MILES
DAMAGE WIDTH: UNKNOWN

Continued chasing eastward on I-40 past sunset, narrowly missing a tornado near Shawnee reservoir, and observing numerous lowerings and a couple of possible tornadoes after dark. Finally stopped at Hulbert, and about 9:45 CDT, decided to end the chase, as I had to be at work the next morning. Crossed the path of the April 14 Tushka/Atoka EF3 shortly after midnight, and arrived back in Austin around 5 a.m.

Another bad day for strong tornadoes hitting populated areas, and a well-deserved high risk call by SPC. I was happy with most of my chase, especially considering how late I started. Missing a couple of minutes of the Washington-Goldsby rope out, and missing at least one other late tornado was frustrating. Still, this was a difficult day with multiple HP cell interactions and fast NE storm motion. Impossible to stay with cells for long when the road network runs mostly NS and EW. A lot of chasers had trouble and went home empty-handed, so I am just glad I got up there in time for one of the main tornadoes.

Special thanks to John S for nowcasting during the crucial Goldsby intercept and later in the evening also to help keep me close to good cells.

NWS Norman page about the outbreak

Depart: Austin, TX 12:30 p.m.
Arrive: Austin, TX 5:00 a.m.
1020 miles, 16.5 hours
Solo chase