On April 17, a number of supercells formed along a dry line northwest of the Carlsbad–Roswell area in New Mexico and tracked generally northeastward, starting around 5:00–6:00 p.m. CST (23:00–00:00 UTC).
Entering West Texas, the storms interacted with a warm front and began producing violent, long-lived tornado families.
The storms likely began generating large hail and weak tornadoes over rural areas in New Mexico, but encountered few structures or observers then.
Ahead of the storms, dew points reached the lower 60s °F as far north as Lubbock, Texas, and slowly moved northward, in tandem with the warm front, after sunset.
A sharp increase in the annual average E/F0–1 count by approximately 200 tornadoes was noted upon the implementation of NEXRAD Doppler weather radar in 1990–1991.
[4][note 3] 1974 marked the first year where significant tornado (E/F2+) counts became homogenous with contemporary values, attributed to the consistent implementation of Fujita scale assessments.
The tornadoes damaged a 20-mile-long (32 km) swath, crushing a pickup truck and killing a few of its occupants, while destroying eight homes nearby, injuring seven people, and doing $750,000 in losses.
East of Claytonville the tornado leveled a few rural homes, one of which it swept away, killing a couple inside and leaving behind some concrete blocks on its foundation.
[70] This violent tornado family first hit Lazbuddie, destroying three farmhouses, killing a woman, injuring at least three people, and causing $500,000 in damage.
After passing near White Deer, this or a related tornado then cut a broken, 5-to-7-mile-long (8.0 to 11.3 km), 100-yard-wide (91 m) swath across southeastern Pampa at F2 intensity, unroofing or severely damaging 20 homes and wrecking many trailers.
After impacting remote countryside for some time, the tornado then leveled a home on each side of U.S. Route 287, west-northwest of Clarendon, badly injuring a woman and killing her husband.
Leaving the community behind, the tornado swept away a trailer on Texas State Highway 70, killing a few more people, and damaged a number of rural farmhouses.
[72] A probable tornado family produced sporadic damage for 40 mi (64 km), tracking over northern Mississippi and southern Tennessee.
In addition, it blew a trailer off its foundation, wrecked a barn, destroyed a CMU print shop, downed trees, and slightly uplifted a school auditorium roof.