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Dallas, April 2, 1957. Location: Arlington Park. The tornado is in the Trinity River bottoms. |
"All photographs are accurate. None of them is the truth." Richard Avedon
This site purposely makes little effort to describe the science -- to the extent that it is understood today -- of tornadoes, but merely to document a specific storm(1). The links and references below will lead you to sources providing good explanations of tornado and severe thunderstorm meteorology plus other useful information concerning tornadoes in general, as well as dramatic images and stories.
A big tornado projects a truly impressive menace that cannot adequately be communicated by video, film, photographs, or words. It has to be seen -- preferably from close by -- to be appreciated. Many tornadoes look positively alive. The difference between seeing one on film and seeing one in real life is the difference between watching a Godzilla movie and seeing some real Godzilla in real life. Nevertheless, when people ask me what the 1957 Dallas tornado looked like I tell them they should go watch the fictional one that carries Dorothy and Toto away to Oz. The physical appearances are not exactly the same, but to this day the sight of this scariest of all movie tornadoes(2) brings back memories.
> National Weather Service Fort Worth Office A short commemorative piece on the tornado. As you would expect, it goes into a little bit of the meteorology. Curiously it has the incorrect 3:00 p.m. time of first appearance that turns up periodically (and that I think likely is due to the Dallas Morning News's error-filled 1997 anniversary story).
> Chasing the Storm: Weather Photography Thanks to Matty from Brooke's elementary school class in Delaware for the link to this interesting weather photography site.
> weatherpix.com This is a Web-based repository of stock weather photography. The link is to the owner's blog entry for April 2, 2007. You'll find some photos that you won't see on the present site, plus links to a little hard core meteorology including a map showing the paths of twenty-five or so tornados that constituted the 1957 Texas-Oklahoma outbreak (right below which you also will find info on another North Central Texas tornado with and April 2 anniversary -- this one in Paris in 1982).
>
Wikipedia has an entry for the "April 2, 1957 Dallas
tornado outbreak," which it presents as a two-day extravaganza of tornado
activity spanning 8 states. And check the link under "see also" for what appears to be an exhaustive list of North American
tornado outbreaks.
>
American
Meteorological Society's "Journals Online" Here are references for a couple of papers
illustrating the scientific use to which data from the tornado was put:
>
Texas Tech's WISE research lab
The following are references with dates for some technical descriptions of the
tornado for which, unfortunately, I do not have the sources. This information
is from Texas Tech's Wind Science and Engineering Lab', which probably has copies of the reports.
>
An Engineering Assessment of Structural Damage in the Altus, OK Tornado: May 11
1982 - Timothy P. Marshall and James R. McDonald - October 1983. Publications that are on the
WISE lab's site include this PDF of a paper which, although
describing a tornado in Oklahoma, notes the significance of the 1957 Dallas
tornado as science's first good opportunity for studying tornado damage to
varying types of construction (if the link fails, just go to the WISE lab's site
noted above and do a search for "Altus").
> The Dallas Public Library's Texas/Dallas History and Archives section has the
complete Weather Bureau report containing the Hoecker references above:
> The report, mentioned elsewhere on this site, resulting
from a U.S. Weather Bureau study of the tornado and its effects that was led by
meteorologist Robert G. Beebe is included in the above DPL reference.
>
On Tornado Funnels , a 1978 scientific paper which suggests a modeling
strategy for tornado funnels based partly on observations of the 1957 Dallas
tornado, might provide interesting reading for anyone possessing a degree in
meteorology.
Wind Speed and Air Flow Patterns in
the Dallas Tornado April 2, 1957 - Walter Hoecker, Jr. - August 1960
Three-Dimensional
Pressure Pattern of the Dallas Tornado And Some Resultant Implications - Walter Hoecker,
Jr. - December 1961.
To access the papers, go to the site (will open in a new window). Select "Advanced Search,"
enter "Hoecker" for "Author Last Name" and "1957 Dallas Tornado" for "Anywhere
in Article" (minus the quotes), and click "Submit Search." PDFs of the complete
papers can be accessed from the search results. Even if you find the meteorology
daunting, you should at least scroll to the "Concluding Remarks" sections of
each paper for expert testimony as to the importance of the 1957 Dallas tornado
for tornado research.
Dallas Tornado - Malcolm Harrison - April 1957
Tornado: State of Knowledge - Edwin Kessler - April 1977
The tornadoes at Dallas, Tex., April 2, 1957 / a collection of reports by
Walter H. Hoecker, Jr., et al. - iii, 175 pp. : maps, charts.
Holdings: Item Holdings DPL Catalogue
Call Number: 551.553 U58Wt.
Publisher: Washington : U.S. Department of Commerce, Weather Bureau,
1960.
This is one of the richest sources of material on the tornado, although
even it seems not to be entirely accurate. Don't accept the library's (very bad) photocopy; make them bring you the original. I
get the impression that copies of this report are in pretty short supply.
(1) For the meteorologically inclined, a quick summary. Obviously there was way more
than adequate atmospheric moisture on (and before) April 2, apparently including an
impressive surface dew point rise from 60 degrees to 70 degrees between 12:30
and 3:30 p.m. on the day of the tornado. The day was warm, even by April in
North Central Texas standards. The cloud base where
the tornado first formed was estimated at ~1100ft. The Lifted Index seems to have
been around -7. At the 500mb level (~18,000 ft) winds of about 40mph were
blowing from the south. Thus moisture, instability, and significant shear all
likely were in place. In addition, a cold front was advancing from the northwest and
was near the area, a stationary front ran along an east-west line virtually on
top of the area (all of the 25 tornadoes in this outbreak occurred north of it
-- the most severe ones virtually on it), and the typical dry line seems to have
been set up out to the west; so a convergence of boundaries was present to help
concentrate the other factors. On a
more "macro-meteorological" scale, a big upper level low was sitting over New
Mexico, the jet stream was split pretty much north and south of the continental
U.S., and a series of low level short wave troughs had been moving across the
country for a number of days. Radar data for the tornado can be found in the
Weather Bureau report, although I
don't know how much help 1957 weather radar info might be in filling out the picture.
(2) Actually a thirty foot long cylinder of muslin run along slots cut in the
top and bottom of the set, plus a lot of dust stirred up by fans.