[3] On April 26, the Storm Prediction Center (SPC) first issued an enhanced risk for the Plains, as a broad upper-trough moved eastwards, with strong tornadic activity erupting in the states of Nebraska, Iowa, and Kansas later that day.

[11] On April 27, a moderate risk was issued by the SPC for areas further south in Oklahoma and millions were put under a particularly dangerous situation (PDS) tornado watch.

[27] This risk was later narrowed to two focal areas: one in northwestern Kansas associated with supercells during the afternoon and evening, and a second near the Red River, associated with an forecast cluster of storms during the overnight hours.

[32] Another cluster of thunderstorms developed in the Permian Basin of Texas in the early overnight hours into April 26,[33] becoming and maintaining severe characteristics as they tracked northeast into the Red River Valley.

[40] With an enhanced risk of severe weather in place, the Storm Prediction issued a tornado watch for eastern Oklahoma on the morning of April 26.

A Doppler on Wheels (DOW) mobile radar truck measured 1-second wind speeds of approximately 224 mph (360 km/h) at a height of ~282 yards (258 m) with the Harlan storm.

In the morning hours of April 27, the Storm Prediction Center issued a moderate risk (level 4) for central Oklahoma, north-central Texas, extreme southwestern Missouri, and southeastern Kansas.

[48] The 00:00 UTC upper-air sounding from Norman, Oklahoma, depicted very strong shear, with storm-relative helicity in the 0–3 kilometer layer of 400 m2/s2 and mixed-layer CAPE of around 2300 J/kg.

[50] Over the course of the successive hours, new tornadic supercells developed ahead of the main squall line and produced multiple large and intense tornadoes in southern and eastern Oklahoma.

[52] This very large, violent, long-tracked tornado first touched down at 3:30 pm CDT south of West Q Road near the Platte River and traveled northeastward, damaging trees and farmstead outbuildings at EF0-EF1 intensity.

[37][53] As the tornado entered the western part of Omaha neighborhood of Elkhorn, it abruptly became violent and widened significantly, striking multiple subdivisions.

[56] This destructive tornado first touched down just north of US 6 in the western part of Council Bluffs, Iowa in Pottawattamie County at 4:54 pm CDT.

It moved north-northeastward at high-end EF1 intensity, producing intermittent damage to the roofs of businesses, homes, and apartment buildings and snapping or uprooting trees.

The tornado strengthened to low-end EF2 intensity as it struck Eppley Airfield, leveling multiple unanchored aircraft hangars and flipping several general aviation airplanes.

Northeast of there, the tornado shifted multiple unanchored homes off their foundations, including one that completely collapsed, destroyed a trailer, and snapped trees.

The tornado then steadily weakened as it continued northeastward over agricultural fields and woodlands, causing EF1 damage to manufactured homes, grain bins, and farm outbuildings, and snapping trees along county roads as it moved into the rural Boomer Township.

The tornado, around three-quarters of a mile wide, then crossed I-80, flipping a semi-truck, and produced a swath of vegetation and building damage to the north of the interstate along York Road.

[37][53][60][22][61] This intense tornado initially touched down in the Chickasaw National Recreation Area at 10:23 pm CDT in Murray County and moved north-northeastward, before turning rightward at a more northeasterly track.

[63] Multiple people were injured in residential areas of Sulphur, including two injuries near a laundromat along West Broadway Avenue (SH-7) which was destroyed; the nearby Mary Parker Memorial Library was also heavily damaged.

[66] The nearby Rusty Nail Winery and a brick United States Postal Service building were also destroyed, with an unknown number of people injured.

[72] Then tornado then weakened to EF1 intensity as it passed over Tull Crest Lake before impacting Ballpark Road, tossing cars and causing more damage.

[75] The tornado then continued northeastward over open terrain, crossing over the Chickasaw Turnpike, entering Pontotoc County, and snapping trees at high-end EF1 intensity before dissipating southwest of Roff at 10:37 pm CDT.

[76][77] Flash flooding in Sulphur may have been a contributing factor to the casualty toll due to high water levels making it difficult to evacuate.

By this time, the tornado had grown to its peak width of 1,760 yd (1,610 m) (or 1 mi (1.6 km)) wide and a much larger area of uprooted trees along with damage to a metal building was noted.

[37][62] After continuing to snap power poles and trees as it turned just slightly east of due north to the northwest of Holdenville, the tornado abruptly intensified to EF3 intensity as it reached County Road E131.

[81] This large, violent tornado developed southwest of Marietta in Love County along Red Oaks Road damaging trees and the roof of a home at EF0 strength.

A large piece of debris from the area landed on I-35 after the tornado passed, narrowly missing a storm chaser on the interstate and a billboard was blown out.

EF0 tree damage continued as the tornado crossed SH-77S twice as it moved through the southern part of Lake Murray State Park near the dam.

[37][62] Through its 25-minute lifespan, the tornado traveled 26.8 miles (43.1 km), had a peak width of 900 yards (820 m), killed one person, injured six others, and caused $151 million in damages.

These include Carter, Cotton, Garfield, Hughes, Kay, Lincoln, Love, Murray, Okfuskee, Oklahoma, Payne and Pontotoc counties.