Jump to content
  • Member Statistics

    17,600
    Total Members
    7,904
    Most Online
    ArlyDude
    Newest Member
    ArlyDude
    Joined

May 24 Plains/MW Severe Threat


Helicity

Recommended Posts

  • Replies 1.6k
  • Created
  • Last Reply

STORM 2... BINGER-EL RENO-PIEDMONT-GUTHRIE

PRELIMINARY DATA...

EVENT DATE: MAY 24, 2011

EVENT TYPE: TORNADO

EF RATING: EF-5

ESTIMATED PEAK WINDS (MPH): GREATER THAN 210 MPH

INJURIES/FATALITIES: UNKNOWN/9

EVENT START LOCATION AND TIME: 8 WNW BINGER 3:30 PM CDT

EVENT END LOCATION AND TIME: 4 NE GUTHRIE 5:35 PM CDT

DAMAGE PATH LENGTH (IN MILES): 75 MILES

DAMAGE WIDTH: UNKNOWN

NOTE: RATING BASED ON UNIVERSITY OF OKLAHOMA MOBILE DOPPLER RADAR

MEASUREMENTS.

Link to comment
Share on other sites

Radars don't scan scan at the surface, they are tilted in elevation.

right...so why would the rating be based solely on radar data? I guess even though that's all it says the rating was based on their must have been other factors involved...

Link to comment
Share on other sites

STORM 2... BINGER-EL RENO-PIEDMONT-GUTHRIE

PRELIMINARY DATA...

EVENT DATE: MAY 24, 2011

EVENT TYPE: TORNADO

EF RATING: EF-5

ESTIMATED PEAK WINDS (MPH): GREATER THAN 210 MPH

INJURIES/FATALITIES: UNKNOWN/9

EVENT START LOCATION AND TIME: 8 WNW BINGER 3:30 PM CDT

EVENT END LOCATION AND TIME: 4 NE GUTHRIE 5:35 PM CDT

DAMAGE PATH LENGTH (IN MILES): 75 MILES

DAMAGE WIDTH: UNKNOWN

NOTE: RATING BASED ON UNIVERSITY OF OKLAHOMA MOBILE DOPPLER RADAR

MEASUREMENTS.

I agree with the rating from the damage photos I've seen, but why would they put doppler radar measurements as the basis for an EF rating?!?!? Why would they not put damage cases in the description to back up this rating? I'm shocked.

Link to comment
Share on other sites

I hear that the mobile radar data indicated that the first tornado from this storm, which crossed US-283 at Lookeba (N of Binger), actually dissipated and that the El Reno-Piedmont tornado subsequently developed somewhere near the Canadian/Caddo Co. line. Interestingly, it appears that the NWS OUN survey has maintained this as all one track.

Also, I was quite surprised to see the radar data used as justification for an upgrade in this age of more stringent ratings, when the 1991-04-26 tornado at Red Rock was not upgraded despite mobile radar-indicated 250+ mph winds. (Not sure what the elevation was of that measurement, but I've seen Dr. Bluestein's video and it crosses the road a couple football fields away, so I imagine it was at least as low as the El Reno case).

Link to comment
Share on other sites

Doppler radar measured windspeeds became a DI? :o

Anyway, thanks for all the updates Attica... this is definitely kinda new here...

I am a little surprised myself. Winds are winds. It all depends on the duration of the winds and how it hits the structure to cause certain types of damage to get an EF-rating. The damage photos did look like they were probably borderline EF4/EF5 so maybe that is why they used the wind measurement as a factor to upgrade the tornado to an EF5.

Link to comment
Share on other sites

I was looking at the winds from the Chickasha tornado and was very impressed.

The CASA radar doppler velocity folds at roughly 75 knots. Obviously you'd expect major wraparound when looking at a beast like this, and being so close to the ground, with such violent winds, noise, and debris, unfolding the data can be difficult.

Below is a image of folded velocity values (in kts.)

Looking for continuity in the values, I believe we may be seeing outbound velocities hit 75kts, and then wrap all the way back to -3kts. If this is correct, we are measuring winds of 147kts (~170 mph) <500m off the ground. You'll certainly see some noise in the velocities, so I am not 100% confident in this measurement, but the continuous values along a few of these radiials suggests they may be correct. I have a few other frames where it's possible the data starts to wrap even further, back into positive territory, but I'm not done with the analysis yet. This would support the EF4 ranking. Although the winds at the ground may not be as high, it's quite likely that the short intervals we are scanning the couplet did not catch the absolute max velocities.

post-992-0-59100400-1307047184.png

Link to comment
Share on other sites

NWS Norman has updated the Lookeba to Guthrie tornado track. It gave me chills. It is blatantly obvious that after approaching I-40, that beast had taken a hard right turn. This continued until just beyond El-Reno, when it veered north. After looking at radar loops, I believe the number of storms in the area is what caused the northward jog, as the parent storm and mesocyclone traveresed the path with greatest instability and less interference from other storms.

Link to comment
Share on other sites

NWS Norman has updated the Lookeba to Guthrie tornado track. It gave me chills. It is blatantly obvious that after approaching I-40, that beast had taken a hard right turn. This continued until just beyond El-Reno, when it veered north. After looking at radar loops, I believe the number of storms in the area is what caused the northward jog, as the parent storm and mesocyclone traveresed the path with greatest instability and less interference from other storms.

Yeah, it is remarkable how close Moore and Norman came to having a huge problem.

Storm3Tracks.jpg

Link to comment
Share on other sites

I was looking at the winds from the Chickasha tornado and was very impressed.

The CASA radar doppler velocity folds at roughly 75 knots. Obviously you'd expect major wraparound when looking at a beast like this, and being so close to the ground, with such violent winds, noise, and debris, unfolding the data can be difficult.

Below is a image of folded velocity values (in kts.)

Looking for continuity in the values, I believe we may be seeing outbound velocities hit 75kts, and then wrap all the way back to -3kts. If this is correct, we are measuring winds of 147kts (~170 mph) <500m off the ground. You'll certainly see some noise in the velocities, so I am not 100% confident in this measurement, but the continuous values along a few of these radiials suggests they may be correct. I have a few other frames where it's possible the data starts to wrap even further, back into positive territory, but I'm not done with the analysis yet. This would support the EF4 ranking. Although the winds at the ground may not be as high, it's quite likely that the short intervals we are scanning the couplet did not catch the absolute max velocities.

Do you guys have to unfold all that data manually or do you have some sort of unfolding program that does most of it for you? I'd say if I were working on a paper or presentation that used raw CASA or DOW data it would take a heck of a long time to get everything unfolded properly.

Link to comment
Share on other sites

  • 1 year later...

Two years already... sheesh. Even more eerie is the idea that this monster central OK day has already been eclipsed by the 19-20 May 2013 sequence. Still, this will always hold a special place in terms of the number of violent tornadic supercells clustered in a small spatiotemporal window. All of the below occurred within ~3 hours and ~75 miles of one another from separate storms.

 

Canton:

 

El Reno:

 

Chickasha:

 

Dibble/Goldsby:

Link to comment
Share on other sites

Archived

This topic is now archived and is closed to further replies.

  • Recently Browsing   0 members

    • No registered users viewing this page.

×
×
  • Create New...