Summers are very hot and rather humid, but from mid-June onward, are relatively dry, with less-severe and less-frequent showers and thunderstorms compared to the late-April to early-June period.
In many years, long stretches of hot, dry weather, punctuated by occasional shower/thunderstorm activity, predominate.
On average, Oklahoma City experiences a secondary peak in precipitation in September and October, compared to the heat and dryness of July and August.
Oklahoma City has a very active severe weather season from March through June, especially during April and May.
Since the time weather records have been kept, Oklahoma City has been struck by thirteen violent tornadoes, eleven F/EF4's and two F/EF5's.
[4] On May 3, 1999 parts of southern Oklahoma City and nearby suburbs suffered one of the most powerful tornadoes on record, an F5 on the Fujita scale, with wind speeds estimated by radar at 318 mph (510 km/h).
[5] On May 20, 2013, far southwest Oklahoma City, along with Newcastle and Moore, was hit again by another EF5 tornado; that one was 0.5 to 1.3 miles (0.80 to 2.09 km) wide and killed 23 people.