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Wednesday, November 9, 2011

Chase Report: 7 Nov, 2011 - SW Oklahoma Cyclic Tornadic supercell


Tornado intercept near Tipton,OK - 3:01-3:15CST



Tornado SSW of Snyder, OK, ~3:23 CS
T


The Details
Departed Austin with chase partner John S at about 7:30 a.m. Slight risk for southern plains, with hatched 10% tornado in SW OK:


Forecast parameters looked good for NW TX/SW OK, including 1000-1500 CAPE and nicely veered profiles. There was some concern that overly moist atmosphere and lack of Convective Inhibition would create conveyer-belt showers and hurt the prospects for discrete cells. Still, with a healthy November jet moving in, and such impressive forecast profiles, felt like it was worth a shot.

Initial target was Childress, TX. By the time we got to Anson, elongated cells were already forming in the east TX panhandle- several hours ahead of forecast initiation from the NAM or HRRR models. Decided to go NE to Vernon to try and stay in front of the activity. Caught initial cell near Quanah, TX and followed it across the Red River on 6. It produced several strongly-rotating lowerings, and one RFD that blew a huge red dust cloud over the vehicle. We did not witness a confirmed tornado from this cell. Images below from 2 p.m. CST, just south of the Red River.


Meanwhile a cell to our SE had quickly become supercellular as it crossed the River. We went South and East out of Olustee, and got our first glimpse of what would shortly become the Tipton tornado. Hail shaft, rain free base, and lowering already apparent, roughly 15 miles away. Time is 2:49, view is SE:

By the time we turned east on 5 and began to approach the town of Tipton, we had a great view of the back side of the cell, with a beautiful hail shaft obscuring a violent tornado in progress. Time is 3:01, view is east:




Shortly after driving through Tipton, we observed the big, dusty tornado as it crossed hwy 5C just to our east at 3:08 CST. Link to youtube video and stills below:

Here is our position for the picture above:

We move slightly east and stopped again, observing the Tipton Tornado move north. Time is 3:10-3:12 CST, view is N:


Over the next couple of minutes, the tornado ropes out. Time is 3:15, View NW:


Here is the NWS PNS regarding this tornado:
PUBLIC INFORMATION STATEMENT
NATIONAL WEATHER SERVICE NORMAN OK
400 PM CST THU NOV 10 2011

...TIPTON TORNADO RATING UPGRADED TO EF4...

BASED ON ANALYSIS OF DATA COLLECTED DURING A GROUND DAMAGE SURVEY...
THE RATING FOR THE NOVEMBER 7TH TIPTON TORNADO HAS BEEN UPGRADED TO
EF4 ON THE ENHANCED FUJITA SCALE. THE RATING IS BASED PRIMARILY ON
DAMAGE OBSERVED AT THE OSU AGRONOMY RESEARCH STATION ON HIGHWAY 5.

THIS IS THE FIRST NOVEMBER EF4 TORNADO IN OKLAHOMA SINCE RECORDS
BEGAN IN 1950.

ESTIMATED WIND SPEEDS IN AN EF4 TORNADO RANGE FROM 166 TO 200 MPH.
As the initial tornado was dissipating, a large low wall cloud formed and begin to produce brief vortices to our NE. Seconds later, the tornado consolidated. Time is still 3:15CST, view is ENE:



We drove east to Manitou, then north up 183, observing the tornado strengthen into a stout stovepipe. View approximately NE, time is 3:20 - 3:24.







The tornado began to weaken as it appraoched 183. It produced this needle funnel in the center of the broad circulation, and seemed to rapidly dissipate shortly thereafter. View is North, time 3:25 CST:



Here is out track and the approximate tornado track during this intercept:



We went east on 62 east of Snyder, where we observed this brief tornado just north of the highway. Time is 3:38, view N.


I believe this tornado briefly had a satellite tornado, but was unable to video this feature. During this same time frame, observed a white funnel under a separate circulation which produced a couple brief surface spinups. Time is 3:40, View N:


Turned north on 54, and then east on mud road E1590. John kept us between the ditches on the treacherous mud roads for the next few minutes, and we witnessed the initial stages of the Wichita Mountain tornado. Time is 3:51, view is E:

We took “Scenic Highway” east, hoping we could catch the cell once we got to the other side. This strategy failed miserably, but we were able to witness the large tornado from time to time when terrain was favorable. Time is after 4:07, view is NNWish:

Here is our position for this leg of the chase, up until the GPS software failed.



Slow traffic and wandering Buffalo killed any hope of catching the cell again.

We dropped south to Wichita Falls, and then to Electra where we intercepted another supercell shortly after sunset. By the time we got to it, the storm had weakened below severe limits, and we ended the chase.

NWS Norman page on Nov 7 tornadoes

Depart: Austin, TX 7:30 a.m.
Arrive: Austin, TX 12:30 a.m.
980 miles, 17 hours

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

Friday, May 27, 2011

Chase Report: 19 May, 2011 - Marathon Bust

Depart: Austin, TX 7:45 a.m.
Arrive: Austin, TX 3:25 a.m.
1303 miles
Solo chase

Phenomena Encountered:
2 minutes of marble-sized hail
1 lame attempt at a wall cloud
1 unfortunate armadillo, now deceased

The ugly truth:
Thanks to D Douglas for nowcasting on a a futile day. The hail and wall cloud both occurred near Kingman, KS with a small, isolated cell that was east of the dryline cells. After that cell dissipated, I made it almost to I-70 just south of the storm that produced the tornado reports in Russell/Ellsworth counties, KS. By then, cells from the south were starting to merge with that one, and it got messy. I decided to cut my losses and turn south, as I had to be back at work Friday morning. Of course, 20 minutes later, the cell north of I-70 ramped up again and produced another brief tornado.

Encountered another dying severe cell on the drive home in OKC. Not a blue-sky bust, but definitely a bust.

ON a positive note, things would get substantially better on my next two chases, May 21 and 24. Reports to come soon...

Wednesday, April 20, 2011

Chase Report: 15 April, 2011, Part 1 - De Kalb to Scooba, MS EF3 tornado



Tornado just North of De Kalb, MS, ~1:22 p.m. CDT.

After a much needed 3 hours of sleep following a long chase on the 14th, I woke up in Little Rock, AR about 7:30 a.m. (all times CDT). A cursory check of models and I was on the road quickly. As I crossed the MS river at Memphis, noted vast area of clearing SW of the initial line mess moving through North MS and West TN. It quickly became apparent that the odds of a big tornado day were increasing. SPC's 1730Z Day 1 included a hatched 15% tornado probability:

There was already a tornado-warned cell in Jackson, MS (which produced EF3 damage), and north of that, a cluster of cells with embedded tornado warnings to my south. I got to Hwy 45 and decided to punch through the cluster to the more isolated cell that was now east of Jackson. I calculated I could catch it near De Kalb, MS.

Arrived at Scooba at 1:07 p.m. The Jackson cell had maintained a tornado warning the entire time, and was now rapidly approaching De Kalb. I went west on 16 and immediately saw the rain-free base and low broad wall cloud. As I got a little closer, saw the top of a cone below the treeline. The wall cloud above this feature exhibited extremely rapid rotation. Called NWS Jackson and reported possible tornado.

Turned around at the junction of 16/39 in De Kalb and hurried slightly east to try to find a suitable spot to observe the area of concern. Pulled off on Old Scooba Road with a good view to the north and observed a large tornado in progress. It was just north of De Kalb, and crossed my field of view over the next 90 seconds. Called NWS Jackson again and relayed the report.

As the wrapping wain curtain on the south side of the tornado arrived at my location, I moved ENE on 16 to reposition. However, it was soon clear I could not safely outrun the tornado on 16, and I stopped to let it cross the highway. All I saw was a solid wall of white, with rapid rotation in the rain curtains as they crossed. Once the back edge had passed, I continued east and noticed a swath of downed trees and powerlines. I was able to safely continue to Hwy 45 at Scooba.

Here is the video- see Video index and map below for details:

De Kalb, MS Tornado Video

Video index:

0:00-1:02 - Driving west into De Kalb through the intersection of Hwy 16 and 39. Wall cloud and brief shot of top of tornado over the treeline. Time is 1:16-1:18 CDT.

1:02-2:52 - Looking ~north from Old Scooba Road. Wedge tornado crossing to my north. Time is 1:20-1:22 CDT.

2:53-4:00 - Driving ENE on 16 between De Kalb and Scooba- low-contrast back edge of tornado crossing highway. Time is 1:32-1:33 CDT.

And here is my position, time, and approximate look angle of the features noted in the video:

Continued east on 16 hoping to trail the tornado until I could navigate back to the SE of it. Instead, I found a tree across 16, and had to turn around and backtrack. Went up to the next eastward road. Delorme 2011 showed that this road would take me into AL at Geiger:

However, after a few minutes of mud and gravel, the road abruptly turned into a grassy, overgrown trail with trees and bushes everywhere:


I could see the storm and wall cloud/fat funnel through the trees, but it was moving away quickly. By the time I got back out of the jungle, I decided I could not catch back up to that cell, and moved back to Scooba to catch the next cells in line.

Here is NWS Jackson's summary of the EF3 tornado.:

http://www.srh.noaa.gov/jan/?n=2011_04_15_tor_neshobakemper

and NWS Birmingham's summary (see Geiger, Sumter, AL portion):

http://www.srh.noaa.gov/bmx/?n=event_04152011

From the wording of the NWS surveys, I believe this was the same tornado, with contiguous damage track. If so, it had a path length of 49 miles, width of up to 1 mile, and duration of 71 minutes.

Over the next 6 hours, observed and filmed several big wall clouds and funnel clouds, but have not confirmed any more tornadoes. I will have to sift thru NWS surveys to see if any of the features I filmed is coincident with tornadic damage. A couple of the features I saw obscured by treelines certainly could have been tornadoes. Will update this report with a part 2 once that work is complete.

As daylight waned, there were still warnings in progress near my location. I was physically exhausted, though, and with flooding issues ramping up, and lack of visual on most of the storms by that time, I decided to call the chase. Spent the night in Meridian, MS and drove back to Austin Saturday. Heard reports of the NC tornadoes during my drive.

Depart: Little Rock, AR 8:00 a.m.
Arrive: Meridan, MS 9:00 p.m.
720 miles, 13 h
2245 miles, 3 day round trip total
Solo chase



Wednesday, March 30, 2011

Chase Report: 26 Mar, 2011- Crazy in Alabama

I-22/Hwy 78 Alabama Supercell
Wall Clouds, Funnels, Phantom tornadoes


Broad, low wall cloud with inflow band near Cordova, AL, ~8:26CDT, 3/26/2011:

Left Austin about 4:45 a.m. (all times CDT). Initial target was Winona, MS, where parameters looked most favorable for afternoon/evening supercells. SPC upgraded a chunk of MS/AL/W GA to MDT on the 1630 Day 1 outlook:

Around the time I was crossing the MS river on I-20, storms fired and rapidly became supercellular near Meridian, MS. A TOR box went up for a swath of AL and GA for this activity. Numerous supercells produced numerous tornado warnings for the next several hours across the watch area. Rather than try to catch this activity, I elected to stick with my original target and turned north on 55 in Jackson. Realistically, I don't think I could have gotten into the initial action in time in AL and GA, and terrain in that area is among the worst I have chased in.

Moving north along 55, I crossed the damage track of the 4/24/2010 Yazoo City super tornado. A swath of trees at least .5 miles long on both sides of the interstate were literally sheared off not far above the surface (20-30 ft). I have seen this signature before from other violent tornadoes- Limestone County AL, 5/18/1995 among others.

Arrived in Winona 2:45 p.m., with clear blue skies and surface temps in low 80's. Quickly noted surface winds were SW, which did not bode well for low-level rotation. With nothing anywhere nearby, I decided to wait, as I was at least near the warm front, and HRRR was showing cells popping in the 22-0Z time frame near my location.

Around 5 p.m., I noted a tower had popped up to my NE. It did not look like much, but I immediately turned back east and went charging after it. A new cell had popped South of the line in North MS, and was now showing up on radar, albeit only weak echoes. As it began to strengthen, it became apparent that it was well ahead of me, 60-80 miles to my NE, and my prospects of catching it weren't great. I had to hope that it would move ESE and track along the warm front and into the moist tongue, which is exactly what it did. I cut NE on 12 at Columbus, MS, with a nice view of the strengthening cell to my NNE, complete with anvil and hard tower. Time is ~6:27, view NNE:

About the time I crossed into AL, the storm went tornado-warned. I got to Guin, AL a few minutes behind the circulation, and noted a possible lowering obstructed by the Guin downtown buildings. No good shots of the lowering at this stage, but one nice lightning capture as I went through town. Time is ~7:20, view is east:

I took 118 E out of Guin through Winfield and Glen Allen in dwindling daylight, continuing to note possible lowerings to my East. I finally approached the radar-indicated circulation near the town of Eldridge, and noted a solid wall-cloud south of my location near Eldridge. I reported this and continued east on 118 through Carbon Hill and onto the I22/78 corridor. Stopped just West of Jasper at 7:58 with a large Wall cloud to my immediate south. Here is the location and appx. look angle of the next few screen grabs:

A couple of moments later, what appeared to be a funnel cloud became evident. Upon careful review of the video, it looks like the funnel is actually behind the wall cloud. Here are a couple of captures:

I began to get rain and small hail, so proceeded ESE on 22/78. Got a couple more looks at the funnelish feature while moving:

At 8:18, I stopped again. Talked to some other chasers, who alerted me to a new circulation just to the North of the highway, in the vicinity of Cordova. At ~8:26, I filmed an ominous wall cloud with protuberances for several minutes. Terrain blocked the lowest level of the feature. Over the next 30 minutes, it would exhibit double wall cloud structure, funnels, inflow tail, and essentially everything but a confirmed tornado. Location and appx. look angle:

Continued ESE on 22/78, filming the area of ciruclation and stopping occasionally. I never saw evidence of a tornado on the ground. During this time, spotter reports of a large tornado prompted continued tornado warnings. These reports turned out to be erroneous, although from my visual evidence at the time, I did not doubt a tornado was in progress.

Despite all these ground-hugging wall clouds, funnels, etc., NWS BMX has not surveyed any tornadic damage from this cell to my current knowledge. That doesn't mean it did not produce briefly a time or two along its path, but without an official damage survey, the video evidence does not support calling any of these features a tornado. The wall cloud/circulation began to get further to my east, and about that time, my outdated version of Delormes had me in the middle of nowhere. Had to call a friend to get me back on track. Made it back to 65, by which time the tornado warning had been canceled.

I stayed on the 65 corridor north of Birmingham for another hour, picking up a couple more cells as they crossed the interstate. Did not see anything else of note, though. Headed towards home, and made it as far as Meridian, MS. Stayed the night in the Relax Inn on the north side of the frontage road on I20 in Meridian. Wasn't the worst dump I have stayed in, although every time I flushed the toilet, water shot out the back of the tank lid. Here is the full GPS log of the chase up until just south of Birmingham, where I disabled the GPS:

Got up Sunday and drove back to Austin. Special thanks to Bill Tabor for providing nowcasting support during some of the hairier moments of the chase.

Depart Austin, TX: 4:45 a.m.
Arrive Meridan, MS 1:00 a.m.
Solo chase
1165 miles, 20h15m
1855 miles 2-day round trip total