The following text contains excerpts from the Texas Department of Water Resources publication "A Review of Texas' Weather in 1979: The Year of Devastating Tornadoes and Flash Floods" published in 1980. The publication was written and prepared by George W. Bomar of Weather Modification & Technology Section of the Texas Department of Water Resources.
From the blizzards that traditionally pound the Panhandle each winter to the enduring heat that scorches vast sections of Texas later in the summer, Texas in the meteorological sense truly is the "Land of Contrast." Perennially the State perseveres through frequent bombardments of hail, high winds, and flash floods, often with the accompaniment of tornadoes-as well as the threat of being struck on its coastal flank by a hurricane or intense tropical cyclone.
Inevitably each year some sector of Texas suffers from the effects of a tornado strike, a blinding snowstorm, a violent hail-bearing thunderstorm, or a raging sand- or dust storm. In many years at least some portions of the Lone Star State experience destruction or severe damage from an untimely freeze, a debilitating drought, or a lengthy spell of excessive rains. Assuredly, no two years weatherwise in Texas are even remotely similar, for the community that reeled one year from a capricious dry spell likely is the recipient of plenty of rain in the following year, while a not-too-distant neighboring locale that hurt from a disastrous hailstorm one Spring experiences relative calm during the following year's storm season.
Very often, those features of Texas weather having the most import-such as the continuation or cessation of damaging drought, occurrences of flash-flooding rains, sharp changes in temperature, and incidences of tornadoes and hurricanes, cannot be discerned from the volumes of meteorological data that are published periodically. This report is an attempt to describe thoroughly but concisely the noteworthy elements of the Texas weather scene throughout 1979.
An explanation of both the causes and effects of the many and varied weather systems that affected Texans during the year has been the central objective of this endeavor. In addition, the author hopes that the analyses will serve as a handy source of reference to those who seek to recall the past and those whose research work attempts to relate the weather to other aspects of human existence.
Those sources of meteorological data used in this report consist of: official rainfall, snowfall, temperature, wind, sunshine, and moisture data as provided by the National Oceanic and Atmospheric Administration (NOAA) in the publications, "Climatological Data: Texas," "Local Climatological Data" (for selected cities), "Storm Data, and "Daily Weather Maps;" weather teletype reports (circuits "A" and "C") from the National Weather Service surface and upper-air observing network; surface and upper-air facsimile charts provided by the National Meteorological Center of NOAA; newspaper accounts; and photographic data obtained by the author.
Rampaging killer tornadoes and devastating floodwaters brought unparalleled tragedy to groups of communities in the Low Rolling Plains and the Upper Coast of Texas during April. The deadliest tornadoes to strike in Texas in 26 years ravaged parts of four communities near the Red River on April 10, taking 53 lives, injuring 1808, and causing damage worth $427 million1.
Barely one week later, phenomenally great amounts of rainfall poured on the southeastern sector of the State, taking 4 lives and inundating parts of numerous communities. Numerous other disruptive weather events, including torrential, flash-flooding rains, scattered but frequent incidents of hail, and a widespread dust and sand storm, highlighted April, an unusually wet but seasonably mild month for most Texans.
A very intense spring storm shifted out of the Rocky Mountains on April 10, generating lines of severe thunderstorms that swept across the northern portion of the State. One group of violent thunderstorms roared across the northern Low Rolling Plains late that afternoon and spawned a series of tornadoes that ripped through four Texas communities.
One of the tornadoes, having a width that varied from 1/2 to 1 1/2 miles, cut a swath of devastation across the southern sector of Wichita Falls in less than 30 minutes, killing 42 persons, injuring more than 1700, and burying dozens of city blocks under tons of debris. A few hours earlier that day, another tornado tore through Vernon, killing 10 residents and injuring more than 60 others. Still other tornadoes struck the communities of Lockett and Seymour a short time later, killing one inhabitant in Lockett.
1 A tornado struck Waco and McLennan County on May 11, 1953, inflicting 114 deaths, 597 injuries, and damages of $4i.2 million. The most recent exceptionally destructive storm to hit the Wichita Falls area occurred on April 3, 1964, when a tornado killed 7 people, injured 111, and caused $15 million in damages, including 225 homes that were completely destroyed.
The killer tornadoes that ravaged parts of three Texas communities near the Red River late in the afternoon stemmed from a wave of very intense thunderstorms that developed shortly after noon when a dry line advanced rapidly eastward out of the High Plains ahead of an approaching Pacific cold front. Earlier in the day around daybreak, low-level moisture from the Gulf was observed pouring northward through the heart of the State while much drier air was surging eastward across the Pecos River (Figure 10).
Other ingredients for a volatile weather situation were also present: a major upper-air trough extending from the southern Rockies into northern Mexico, migrating eastward into western Texas and deepening significantly at the same time (Figure 11); a strong wind shear from the surface to 500 millibars and a thin layer of very moist air at the surface with rapid drying immediately above at about 700 mb (Figure 12 and Figure 13).
The atmosphere in the Low Rolling Plains was highly unstable (with a Totals Index above 50 and a strong positive K Index extending southward out of western Oklahoma); very vigorous lifting of such unsettled air by the advancing dry line seemed sure to trigger violence (Figure 14). With surface pressures in the southern High Plains plunging rapidly, a low pressure center formed in the vicinity of Lubbock around noon (Figure 15).
As the much drier air whipped eastward out of the southern High Plains just after noon, thunderstorms, some of which were very heavy, boiled up in parts of the eastern High Plains and quickly spilled over into the Low Rolling Plains. A few intense thunderstorms erupted at about the same time in the northwestern portion of North Central Texas; small hail and high winds raked Gainesville and Decatur during the noon hour. Soon thereafter tornadoes were spotted near Crosby ton and Plainview and golfball size hail fell near Tulia, Afton, and Washburn (High Plains).
Meanwhile, strong gusty winds associated with the eastward progression of an intensifying upper atmospheric storm out of New Mexico made travel hazardous in. much of the Trans-Pecos region. Winds gusted the 93 miles per hour (mph) in Guadalupe Mountain National Park at mid-afternoon, while wind gusts of 60 mph or more stirred up dust and sand that reduced visibilities at many points from El Paso to Midland to 3 miles; at Lubbock visibilities dropped to 1 1/2 miles by late afternoon.
By mid-afternoon the surface low had migrated northeastward toward the northern Low Rolling Plains, where steep pressure falls of up to 8mb or more in three hours were observed (Figure 16 insert). While the leading edge of the moist, tropical air had already surged northward across the Red River, giving Wichita Falls a vigorous southeasterly wind and a climbing dew point (Figure 16), the advancing edge of much drier, continental air swept eastward out of the High Plains and undercut the less dense and more moist tropical air. Childress lay in the path of the advancing low pressure center, as surface pressure fell drastically and winds backed during the afternoon before the much drier continental air enveloped the region in the evening (Figure 17).
The effects of passage of both the warm front from the Gulf and later the dry line from the west were pronounced at points like Abilene, where rapidly falling surface pressures, a soaring temperature, and a sudden plunge in dew point (signaling the arrival of the dry line) identified well the events that combined to cause devastation farther to the north a few hours later (Figure 18).
Why the Red River Valley between Childress and Bowie received the most severe outbreak of thunderstorms is explained by Figures 19-26. The most active portion of the advancing dry line traversed this sector of the Low Rolling Plains at precisely the time of occurrence of the tornado outbreak (Figure 19). A sharp temperature gradient immediately preceded the movement of the drier air into the region at 850 mb (Figure 20), while at 700 mb the axis of maximum winds was positioned directly overhead the upper Red River valley (Figure 21) and appreciable vertical motion was evident (Figure 22).
At about the mid-point in the atmosphere (around 500 mb), significant cold air advection occurred, thus exacerbating unsettled conditions, already present (Figure 23). The highly unsettled atmosphere out ahead of the advancing dry air is illustrated by the sounding taken at Stephenville just as the gargantuan tornado was hitting Wichita Falls; the lowest 300 mb of the atmosphere was highly convectively unstable (Figure 24).
Stability indices indicated the air throughout central. Texas was extremely unstable early in the evening (Figure 25). Meanwhile, behind the dry line and cool front in the High Plains, the atmosphere quickly stabilized, and drying out was evident in the lower half of the atmosphere below 500 mb (Figure 26).
Numerous other thunderstorms trekked across the area between Abilene, Wichita Falls, and Brownwood during the early evening, as the surface front, now occluded in the Panhandle, pushed relentlessly eastward. For the most part, however, rainfall amounts were modest, with only a few points collecting more than 1 inch (Figure 27).
By dusk a strong of new, very intense thunderstorms formed farther south in Texas. This line raced northeastward, spilling heavy rains, hail and high winds on numerous communities. A thunderstorm that pelted the Coleman area with golfball-size hail also generated a tornado that caused considerable damage to power lines and outbuildings north of the city. A second severe thunderstorm pounded the area just north of Brownwood with hail having a diameter of 3 to 3 1/2 inches.
Violent weather became more widespread as the afternoon progressed. The first in a series of tornadoes struck near Foard City shortly after 3 o'clock destroying several rural homes, barns, and farm equipment. Then, a second vicious tornado formed near Thalia and moved into Lockett, where a driver of an auto was killed when her vehicle was thrown 200 yards off the highway.
A short time later, the same tornado invaded Vernon, taking the lives of 10 inhabitants and injuring 67 others. The Vernon tornado destroyed a restaurant, motel, a farm implement store, and more than a dozen homes; damage totaled $27 million. Half of the injuries sustained by Vernon residents were deemed critical by city officials. Another tornado swept the community of Harrold soon thereafter, causing much less extensive damage. The thunderstorm that fostered that tornado also produced hail up to 3 inches in diameter west of Harrold.
A fourth tornado touched down just outside of Seymour an hour later, but again damage was comparatively minor. The huge thunderstorm that yielded the Seymour tornado also pounded Holliday with baseball-size hail and an area west of Iowa Park with golfball-size hail.
The most devastating tornado of the day dipped from a thunderstorm (with a top estimated at 58,000 feet) that was moving northeastward into Wichita Falls at a speed of 35 miles per hour a few minutes before 6:00. Within 30 minutes the tornado, with a track that varied between 1/2 and 1 1/2 miles wide and 8 miles long, had sped across the southern portion of Wichita Falls.
Forty-two people were killed outright by the storm, while 3 others died of heart attacks. Twenty-five of the deaths were. auto-related; 16 of that total died while in their autos trying to flee the storm, and 11 of that number abandoned homes not touched by the tornado.
Three thousand and 95 homes were destroyed while roofs of many other buildings were sheared away. More than 1700 injuries occurred within Wichita Falls. One thousand and 62 apartment units and condominiums were destroyed, and 93 mobile homes were demolished. Wrecked cars were smashed against bridge abutments, a power plant was knocked out, and part of a high school was destroyed.
Total damage in the city was estimated at $400 million; five thousand families (or about 20,000 people) were left homeless. This most damaging tornado in Texas history was not finished, however. It sped into Clay County, causing no deaths but 40 injuries and damage in the communities of Dean and Petrolia that amounted to $15 million. Golfball-size hail fell prior to and immediately after the tornado passed along a track that took it into Oklahoma (where it dissipated near Waurika).