Begin forwarded message:

 

Resent-From: <lbosart@ALBANY.EDU>

From: Clark Evans <a.clark.evans@gmail.com>

Subject: El Reno tornado phased array radar loop

Date: 4 June, 2013 04:40:20 GMT+00:00

To: <MAP@listserv.albany.edu>

Reply-To: Clark Evans <a.clark.evans@gmail.com>

 

Hi all,

 

To add to the discussion of the chaser activity surrounding the El Reno tornado, I'd like to pass along this radar loop of the storm that was put together by the WDSS-II team. The radar data comes from the National Weather Radar Testbed phased array radar at the Norman, OK airport.

 

Note how the high spatiotemporal resolution of the radar product shows the southward development of the supercell's hook to the south-southwest of El Reno, followed by the mesocyclone subsequently being "swallowed" back northward into the supercell's "belly" as the storm moved east of El Reno. Other aspects of the storm's evolution are also noteworthy, of course.

 

-Clark

 

 

---

Clark Evans

Assistant Professor, Atmospheric Science Group

Department of Mathematical Sciences

University of Wisconsin-Milwaukee

E-mail: a.clark.evans@gmail.com

Phone:  414.229.5116

Web:    http://derecho.math.uwm.edu/

Begin forwarded message:

Resent-From: <lbosart@ALBANY.EDU>

From: Howie Bluestein <hblue@OU.EDU>

Subject: Fwd: El Reno tornadoes

Date: 3 June, 2013 01:25:47 GMT+00:00

To: <MAP@listserv.albany.edu>

Reply-To: Howie Bluestein <hblue@OU.EDU>

 

 

From: Howie Bluestein <hblue@ou.edu>

Date: June 2, 2013 7:49:22 PM CDT

To: <map@atmos.albany.edu>

Cc: Howie Bluestein <hblue@ou.edu>

Subject: El Reno tornadoes

 

Hi all:

 

In response to many requests for comments, I'm sending you copies of my status update messages from yesterday and today. I'd be happy to comment specifically on the dangers of chasing tornadoes from my perspective, but not now because I haven't the time, and not now because I'd rather not participate in a discussions while emotions are running so high.

 

Howie Cb

 

Howie Bluestein

hblue@ou.edu

 

Howard B. (Howie "Cb") Bluestein

Professor and George Lynn Cross Research Professor

School of Meteorology

University of Oklahoma

120 David L. Boren Blvd., Suite 5900

Norman, OK 73072-7307

 

405-325-6561

FAX 405-325-7689

 

Amateur Radio K1RHZ

 

 

Begin forwarded message:

From: "Bluestein, Howard B." <hblue@ou.edu>

Date: June 1, 2013 11:33:59 AM CDT

To: "Snyder, Jeffrey C." <jsnyder@ou.edu>, "Houser, Jana B." <jana.b.lesak-1@ou.edu>, "Mahale, Vivek" <vmahale@ou.edu>, "Palmer, Robert D." <rpalmer@ou.edu>, "Meier, John B." <pi@ou.edu>, "Bodine, David J." <bodine@ou.edu>, "Zhang, Guifu" <guzhang1@ou.edu>, Robert Bluth <rtbluth@nps.edu>, Paul Buczynski <PBuczynski@nps.edu>, David Lary <djl101000@utdallas.edu>, "Andrew L. Pazmany" <pazmany@prosensing.com>, "Tanamachi, Robin L." <rtanamachi@ou.edu>, Dan Dawson <Dan.Dawson@noaa.gov>, "Carr, Frederick H." <fcarr@ou.edu>, Morris Weisman <weisman@ucar.edu>, "Welch, Kathleen E." <kwelch@ou.edu>, "Cavallo, Steven" <cavallo@ou.edu>, John Brown <john.m.brown@noaa.gov>, "Parsons, Dave B." <dparsons@ou.edu>, Lance Bosart <bosart@atmos.albany.edu>, William Harrison <wah091020@utdallas.edu>, "Kurdzo, James" <kurdzo@ou.edu>, Stephen Moore <prothermographer@gmail.com>, Roger Wakimoto <wakimotoroger@gmail.com>, Zachary Wienhoff <wienhof1@illinois.edu>, "Reif, Dylan" <dylanreif@ou.edu>, "Thiem, Kyle J." <Kyle.J.Thiem-1@ou.edu>, Chris Weiss <chris.weiss@ttu.edu>, "Biggerstaff, Michael I." <drdoppler@ou.edu>, Davina Bristow <davina.bristow@bbc.co.uk>, "Burgess, Donald W." <Donald.Burgess@noaa.gov>

Cc: "Bluestein, Howard B." <hblue@ou.edu>, "Wicker, Louis J." <louis.wicker@noaa.gov>, Michael French <mmfrench1981@gmail.com>

Subject: status update

 

Hi all:

 

Yesterday:  Collected data using RaXPol in a number of tornadoes near El Reno and points east and southeast (see sample data below courtesy of Jeff). 1st deployment just N of El Reno, up to 40 deg elev angle, documenting first storms and collision of S storm into storms to N; 2nd deployment, S or SW or SE of El Reno, documenting entire genesis to maturity of large tornado, satellite tornadoes, and an anticyclonic tornado. Great photos of storm structure and broad tornado. Tornadoes formed to our W and moved ESE'wd to our SSW; had to leave to escape large hail and gust front. It seems we get into position too often N or NE of the hook. Early scans were deep volumes; when tornado was close and mature, we scanned 0 - 5 deg in one deg increments. More deployments, some stationary, some while moving. Tornado dissipated and a new one formed just W of us at the tip of an RFD surge while we were on I-40. Managed to stay E of tornado on I-40 (see WSR-88D images at end). Some small pieces of debris were falling onto I-40 just ahead of the radar truck as we strategically retreated to the E. Last deployment was E of OKC on I-240 S of Tinker Air Field. Major interstates were parking lots. Very dangerous situation, since tornado or potentially new tornado could have hit where traffic was at a standstill:  Lesson...don't get on an interstate to try to outrun a tornado. An emergency manager escorted us with sirens and flashing lights off an exit, bypassing all the traffic. Went home via Choctaw Rd. and around Lake Thunderbird onto Stella Rd. ("Stella!! Stella!! apologies to Tennessee Williams and Marlon Brando and Jerry Seinfeld) to Rt 9. Power flashes at intersection of Stella and 9, but wind not strong there. Back to W through tip of hook and safely home about 9:15 PM. No power last night and still no power at our house. Special thanks to Jeff who worked hard to collect data and navigate and to Jana, who drove safely and expertly. Much more detailed and more accurate documentation to come later. Hope other radars were out and there can be some intercomparisons or even dual-Doppler.

 

P. S. - Does Jeff ever sleep? Just got e-mail showing some scans from Banner Rd. near I-40 with wind speeds as high as 118 m/s inbound at 4.75 km range at 1 deg elev. angle and 95 m/s outbound at 4 km and 1 deg elev angle. Jeff reports many of the maxima were with subvortices rotating around the main axis of the tornado.

 

Today and tomorrow:  Down, thank goodness.

 

Next week:  Possible field ops as moisture backs up onto High Plains underneath weak to moderate NW/W flow. Will re-assess later. May be field ops SW KS, OK Panhandle, N TX Panhandle.  Crew:  Jeff, Vivek (?), and I. Am not leaving for Boulder quite yet. What an amazing season!

 

Howie Cb

 

Note two eyes and vortex signatures; spiral bands of debris seen in rhohv.

 

Frame grabs below from my iPhone of WSR-88D Doppler velocity and radar reflectivity factor from KTLX as we were being chased by a tornado down I-40. Our GPS location is indicated by the blue circle. I-40 is the purple line.

 

 

Hi all:

 

I am sad and shocked to tell those of you who have not already heard that Tim Samaras, his son Paul, and Carl Young died while chasing the El Reno tornado on Friday. While I have been receiving unconfirmed reports of this since early this morning, the most recent, from Channel 7 in Denver (via Lou Wicker), seems to confirm this tragic news. I have known Tim for many years as someone who shared our enthusiasm for severe weather. He designed some of the early miniature instruments deployed in the paths of tornadoes, particularly those with video cameras and temperature and pressure sensors. His work has been showcased and supported in part by the National Geographic Society, and displayed at the Denver Science Museum. More recently he has been working with high-speed lightning cameras. We have in the past, for a number of years, shared our groups' status-update messages. He and Roger Hill ran the very successful National Tornado Chasers' Convention in Denver each February. He was always a gentleman and shared his enthusiasm with the community. While not an academic or a member of a meteorological research laboratory, he has had a profound influence on all of us, and in particular through publications of the analyses of his data from TWISTEX. 

 

On a related note, Jeff and Jana have found unofficial evidence of wind speeds as high as 130 m/s in one of the satellite vortices we probed with RaXPol on Friday. I prefer this estimate to remain unofficial  (it may be propagated, but only as UNOFFICIAL) until we have all had time to inspect the data in detail. I do not want to rush to get this out just for its sensational effect, but would prefer to be certain. Tim Marshall, Don Burgess, and Gabe Garfield conducted a damage survey of the tornado yesterday. Roger and Jeff, independently, conducted partial surveys. Much of the most intense portion of the tornado's life was fortunately over open country where the potential for loss of human life was minimized. In addition, markers are few and there will likely be a controversy of what the rating of this tornado should be. We will come up with an official radar estimate of max winds and someday publish it. If the NWS rating is much less than EF-5 based on markers, then so be it. Recently, radars have frequently been used to upgrade damage estimates, thus corrupting the long-term record. Someone will undoubtedly use recent increased numbers of strong tornadoes to infer that tornado intensity has been increasing. 

 

Data were collected also by AIR from a longer range, to our south, and by a SMART-R. It may be, after the dust has settled, that dual-Doppler analyses may be possible, especially because our locations seemed to have been to the north of most ot the other radars. NOXP at North Base might be usable later on when we reached OKC and E. I have heard reports that the Rapid DOW was out, but I have no information on their deployment locations and times. We should discuss all this next fall when I return to Norman. I hope to leave for Boulder after the next possible field ops in the High Plains.

 

Today:  down; enjoy the cool and dry weather.

 

Tmw.: Moisture progged to return tmw afternoon and high-based storms psbl on the High Plains, particularly over SW KS and possibly the TX Panhandle, where under moderate westerlies or NW flow supercell shear is possible. Standby for possible relatively early departure. Cap will be substantial, but storms that do form should have high temp - dew point spreads. Not sure if travelling such a long distance will be warranted. Stay tuned. Early June can be a good time for photogenic storms and good data collection opportunities.

 

Tues.:  Sfc cyclone progged to be near Childress; adequate moisture and shear for supercells expected in OK, but could be capped. Most likely CI NE of cyclone along the front in OK. Field ops likely.

 

Weds.:  A possible convective mess, as activity could occur all day as Gulf air rides up over a front near the Red River. Tropical cyclone forming in the E Gulf of Mexico?

 

Byeondo:  Weak NW flow. Predictability low, but system should pass on Sat. with CI. Details unclear.

 

Howie Cb

 

 

 

 

Howard (Howie "Cb") Bluestein

Professor of Meteorology and George Lynn

        Cross Research Professor

School of Meteorology

University of Oklahoma

120 David L. Boren Blvd., Suite 5900

Norman, OK 73072

 

Main office 405-325-6561

FAX 405-325-7689

Office direct (upon request)

Cell (upon request)

 

 

 

 

 

 

 

 

 

Begin forwarded message:

Resent-From: <lbosart@albany.edu>

From: Clark Evans <a.clark.evans@gmail.com>

Subject: OU RaXPol image of the El Reno tornado

Date: 4 June, 2013 19:07:17 GMT+00:00

To: "Bosart, Lance F" <lbosart@albany.edu>, "Guastini, Corey T" <cguastini@albany.edu>, Morris Weisman <weisman@ucar.edu>

 

Probably not best for widespread map-list distribution until/unless Howie has the chance to clarify, given that I am not certain of how it came to be on social media. (RaXPol images are posted here)

 

Also of note: a PowerPoint slide put together by the Norman WFO describing, in a bit more detail, how the radar data were used to estimate the tornado's maximum intensity.

 

-Clark

 

 

--

Clark Evans

Assistant Professor, Atmospheric Science Group

Department of Mathematical Sciences

University of Wisconsin-Milwaukee

E-mail: a.clark.evans@gmail.com

Phone:  414.229.5116

Web:    http://derecho.math.uwm.edu/

 

 

 

Begin forwarded message:

Resent-From: <lbosart@albany.edu>

From: "Steven J. Weiss - NOAA Federal" <steven.j.weiss@noaa.gov>

Subject: Fwd: Significant Event Report -- Severe Weather from Texas to the Great lakes, also Flooding Potential for the Missouri and Mississippi River Basins

Date: 31 May, 2013 19:05:38 GMT+00:00

To: "Bosart, Lance F" <lbosart@albany.edu>

 

Lance,

 

Assuming you may be at MPEX now.  The last day or two is another example of combined severe storms/heavy rain/flooding that causes considerable challenges in forecasting and communication of threats.

 

Enjoy Boulder.

Steve W

 

 

---------- Forwarded message ----------

From: National Weather Service Operations Center

 

Severe Weather from Texas to the Great lakes, 

also Flooding Potential for the Missouri and Mississippi River Basins

 

 

Key Points

    Conditions remain favorable for severe weather from Texas to the Great Lakes today.

    Severe potential moves slowly eastward over the weekend.

    NWS Storm Prediction Center (SPC) is again forecasting a Moderate Risk of severe weather today for eastern Oklahoma, including the Oklahoma City Metro and the Moore recovery area, as well as extreme southeast Kansas and southwest Missouri

    In addition, continuing heavy rainfall is likely into Saturday for the Missouri and Mississippi River Basins.

                     Flash flooding and river flooding could be significant in parts of Iowa, Missouri and Illinois into next week.

Reported Impacts from Thursday and This Morning

                      

    Several reports of severe weather on Thursday:

                     Broken Arrow, Oklahoma: Damage to homes/businesses.

                     Emergency Management reporting one fatality in Tull, Arkansas from to a tree falling on a vehicle.

                     Softball-size hail was reported in Bray, Oklahoma.

                     Reports of strong thunderstorm winds over 60 mph were reported from the central Plains to the Great Lakes, with 80+ mph gusts in Des Moines, Iowa.

    Heavy rainfall continued over Iowa, Kansas, Oklahoma and Arkansas on Thursday, resulting in significant river rises.

    The Scott County, Arkansas Sheriff's body was found after going missing in a flash flood.

    There is a dam over-topping in Boonville, Missouri. Flash Flood warning issued by WFO Pleasant Hill, Missouri for locations downstream.

Expected Impacts

    Severe Thunderstorms:

                     Today:

                                       A Moderate Risk for severe weather exists again today over eastern Oklahoma, which includes tornado recovery areas, as well as southeast Kansas and southwest Missouri.

                                                         A regional severe weather outbreak is possible in the Moderate Risk area.

                                                         Portions of central/eastern Oklahoma will be considered for an upgrade to a High Risk at 4:00pm EDT dependent on conditions at that time.

                                                         Strong or violent tornadoes are possible in this area beginning mid-afternoon.

                                                         Very large hail and widespread damaging winds are also forecast with any storms that develop.

                                                         The risk switches to heavy rainfall later this evening, with some locations in this area receiving over 4 inches of new rainfall.

                                       Slight Risk for severe weather exists today from northern Texas to the Great Lakes.

                                                         Large Hail and damaging winds are the main threat, although a few tornadoes are also possible.

                      Saturday:

                                       A Slight Risk of severe weather is possible from central Texas through the mid-Mississippi Valey into the Southern Great Lakes.

                                                         Highest probability for severe weather will be from northeast Arkansas into Indiana and Ohio, as well as southcentral Texas.

                                                         Main threats will be from strong winds and large hail.  A few tornadoes are also possible

                     Sunday:

                                       A Slight Risk of severe weather is forecast from from the Mid-Atlantic into central New England, as well as far southwest Texas and southeast New Mexico.

                                                         For the mid-Atlantic/New England: Damaging winds will be the primary hazard, although some large hail and a possible tornado cannot be ruled out.

                                                         For Texas/New Mexico: Large hail is the primary hazard, with isolated tornadoes possible.

    Flooding:

                     An additional 3 to 7 inches of rain fell over central Arkansas Thursday.

                     2 to 4 additional inches of rain fell over already saturated areas in Iowa, Illinois and Missouri.

                                        Rivers in those areas are responding to the rainfall reaching moderate to major flood stages.

                                                         Evacuations are being ordered along the Cedar River and Beaver Creek in Iowa.

                                                         Evacuations may be ordered in Iowa City and Coralville, Iowa in response to dam releases.

                                       The central Mississippi River is also responding to the rainfall, with major flood stages forecast to continue into later next week.

                                       The flood risk is not expected to be high for the Lower Mississippi River at this time.

                     An additional 3-6 inches of rainfall is forecast from northeast Oklahoma to southern Michigan into Sunday morning

                                       River stages in the northern and central Mississippi River basin will increase to major flood levels at many locations.

                                       Flash flooding will be possible in these areas.

                     Flood Warnings and Advisories are posted for eastern Montana and Western North Dakota due to 2-3 inches of rainfall that occurred Thursday.  An additional 1-2 inches will fall today.

NOAA/NWS Activities

    NWS Weather Forecast Offices (WFO) in the affected areas have been briefing local emergency management officials and the media well in advance of these events

    NWS Southern and Central Regional Operations Centers are briefing FEMA Regions in their areas.

                     NWS Southern Region Operations Center deployed an Emergency Response Specialist to FEMA Region VII Wednesday.

    NWS Storm Prediction Center has been briefing FEMA HQ since Sunday regarding the increasing threat for severe weather.

    The NWS North Central River Forecast Center (NCRFC), as well as the Arkansas Red River Forecast Center (ABRFC) are in 24 hour operations until further notice for the major flood threat.

    WFO Des Moines, Iowa has deployed a meteorologist to the Iowa Operations Center, and is also briefing Joint Forces Headquarters.

    The Missouri Basin River Forecast Center is coordinating with the US Army Corps of Engineers regarding 5-day crests.

Links

    Current National NWS Hazards

    NWS Weather Prediction Center - Quantitative Precipitation Forecasts

    NWS Storm Prediction Center - Convective Outlooks

    NWS Storm Prediction Center - Storm Reports for Wednesday

    NWS Advanced Hydrologic Prediction Service (AHPS) River Forecasts

    NWS Weather Prediction Center Significant River Flood Outlook

Graphics

 

Radar estimates of rainfall amounts since May 30, 2013.

 

NWS Weather Prediction Center (WPC) precipitation forecast - 

valid Friday through Sunday morning (May 31-June 2, 2013)

 

NWS Storm Prediction Center Graphics Depicting Severe Threat Areas for 

Friday, Saturday and Sunday May 31-June 2, 2013

 

WFO Norman, Oklahoma Severe Weather Forecast.

 

 

Information in this report was provided by the NWS Central and Southern Region ROCs, WFO Norman, OK, NWS Storm Prediction Center and the NWS Weather Prediction Center.

 

 

--

Duane Carpenter

Meteorologist In Charge

National Weather Service Operations Center

U.S. Department of Commerce

 

 

 

 

--

Steven J. Weiss

Chief, Science Support Branch

NOAA/Storm Prediction Center

120 David L. Boren Blvd., Suite 2300

Norman, OK 73072

405-325-2073 (office)