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Possible Owasso, OK Tornado?

gdlewen

EF2
Joined
May 5, 2019
Messages
191
Location
Owasso, OK
I'm not sure this qualifies as an "EVENT", and since it bears on @Mike Smith 's discussions of NWS Tornado warning procedures, I'm posting it here.

One of the cells that moved through Owasso, OK last night developed a strong mesocyclone that intensified as it moved W-to-E south of Owasso. As the circulation passed, winds increased from the south and then shifted rapidly to northerly. At the peak, the sound of wind and wind-driven rain drowned out the thunder from frequent cloud-ground lightning. (No longer any need to clean my exterior windows.)

I am posting the Tulsa TDWR because it is more nearly south of Owasso than is KINX, so the storm motion is more normal to the radar scan direction. That is to say: the fact that RadarScope doesn't offer storm-relative radial velocities for TTUL is less of an issue when interpreting the velocity pattern. The center of rotation passed about 1.5 miles south of my house.

I think this velocity pattern "suggests" tornado and I do wonder why no warning was issued. (The gate-to-gate velocity difference, based on the RadarScope display, is about 110MPH. Also, the lowest scan is sampling the atmosphere at a height of about 500ft at the very "center" of the circulation.)

TTUL_20230814_0512Za.jpg

Tulsa Nexrad (KINX) radar at this time had trouble with the radially-outward winds over the Turley-Owasso area:

KINX_20230814_0511_SRV.jpg

Trees and power lines are down all over Owasso, and there is a swath of storm damage from Turley across Owasso, which, obviously, could be due to straight-line winds. The winds snapped off about a dozen of my fence posts, with the most obvious indication of strong northerly winds seen below:

IMG_7715.jpg

My instinctive response is that this was too short-lived an event for a warning. Perhaps 20-30 minutes from the time it caught my attention to the point where proximity to the KINX site made it hard for me to interpret what I was seeing.

Is that a fair response? I haven't been in a WSO office during bad weather for many years, but I have no problem remembering how crazy things got. Also, it's easy for me to focus on a given feature in the overall system of cells and supercells and stay with it, since I am a "fixed target" with a limited "region of interest", while the WSFO has responsibility for the entire county and beyond.

It will be interesting to see how this is handled when storm damage is surveyed.
 
Looks like they successfully warned on it, even including the 70mph gust potential? ASOS in Tulsa hit 65mph.

WUUS54 KTSA 140445
SVRTSA
OKC037-111-113-131-143-145-140530-
/O.NEW.KTSA.SV.W.0335.230814T0445Z-230814T0530Z/

BULLETIN - IMMEDIATE BROADCAST REQUESTED
Severe Thunderstorm Warning
National Weather Service Tulsa OK
1145 PM CDT Sun Aug 13 2023

The National Weather Service in Tulsa has issued a

* Severe Thunderstorm Warning for...
Southwestern Rogers County in northeastern Oklahoma...
Southeastern Osage County in northeastern Oklahoma...
Northeastern Creek County in northeastern Oklahoma...
Western Wagoner County in northeastern Oklahoma...
Northwestern Okmulgee County in northeastern Oklahoma...
Tulsa County in northeastern Oklahoma...

* Until 1230 AM CDT.

* At 1145 PM CDT, severe thunderstorms were located along a line
extending from near Mannford to 2 miles northwest of Kellyville,
moving east at 55 mph.

HAZARD...70 mph wind gusts.

SOURCE...Radar indicated.

IMPACT...Expect considerable tree damage. Damage is likely to
mobile homes, roofs, and outbuildings.

* Locations in or near the path include...
Tulsa... Broken Arrow...
Sand Springs... Bixby...
Sapulpa... Jenks...
Glenpool... Coweta...
Catoosa... Mannford...
Kiefer... Mounds...
Kellyville... Porter...
Jenks Riverside Airport... Stonebluff...
Keystone State Park... Turley...
Tulsa International Airport... Oneta...

This includes Interstate 44 between mile markers 202 and 238.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

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

&&

LAT...LON 3616 9627 3618 9626 3626 9609 3625 9576
3586 9552 3583 9622 3616 9631
TIME...MOT...LOC 0445Z 276DEG 48KT 3615 9634 3598 9624

THUNDERSTORM DAMAGE THREAT...CONSIDERABLE
HAIL THREAT...RADAR INDICATED
MAX HAIL SIZE...<.75 IN
WIND THREAT...RADAR INDICATED
MAX WIND GUST...70 MPH
 
Looks like they successfully warned on it, even including the 70mph gust potential? ASOS in Tulsa hit 65mph.

Yeah, sorry about that. I wasn’t clear about what was warned and what was not. We had multiple severe thunderstorm warnings as cells paraded through. And a flood warning. Our weather radio was going off at regular intervals.

But no tornado warning. I’m just curious if the radar signature would justify a tornado warning.

In driving around we saw a few utility poles snapped off 10-20 feet above ground, all “pointing” S. We also have a report of 95 MPH wind gusts NW of Catoosa, about 9 miles SE of Owasso (media report.)


 
But no tornado warning. I’m just curious if the radar signature would justify a tornado warning.

I believe it would have. I've noticed the discontinuous wind speed pixels in the TDWR velocity data often show up when tornadoes are being observed by the radar.
 
What was the survey outcome?

As far as I can tell there was no damage survey anywhere in NE OK. I assume some survey of storm damage took place, but nothing seems to have been reported either at Tulsa NWS or in the news. A damage report may be in progress, or I am not looking in the right place; certainly, the Tulsa Twitter feed has no mention of anything. A week later...perhaps the world has moved on?

Did see this down the road, though--a stoplight bent so it faces SE (photo looking N). Did the storm cause it? Obviously, I can't say. Sunday it was "fine". Monday it was "bent". I can't explain it. But fun to speculate the same strong northerly winds that brought down fences and snapped off telephone poles were responsible. [shrugs]

IMG_7776.jpg
 
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