Flood disaster in Texas and Oklahoma

June 2, 2015

Flood disaster in Texas and Oklahoma

A constant delivery of the necessary ingredients for heavy rains has meant record-breaking rains and flooding spread out over several weeks.

While no single day in Oklahoma City has come close to the 7 inches of rain that fell in 24 hours, the city has still received repeated heavy rainfall for much of the month, including 3.73 inches on May 23. The city totaled 19.48 inches of rain during the month of May, smashing not only the previous May record of 14.52 inches (set in 2013), but also the all-time wettest month on record, which was 14.66 inches in June 1989. In short, the city has recorded almost 5 inches more rain than it ever has before in a single month. The city receives only 4.65 inches in May on average.

This hasn’t been just a wet period for Oklahoma City; the entire state has recorded a great deal of precipitation. May rainfall has been at least 200% greater than normal statewide, with southern Oklahoma seeing rains 400% above average (over 20 inches of rain). For reference, the 30-day accumulated total (May 2-31) of over 23 inches of rain near Oklahoma City according to one weather station would be a greater than a 1-in-1000 year event. This means that every year there is only a 0.1% that any 30-day period would record that much rain.

The wet weather was not simply an Oklahoma affair. Texas has also received its fair share of drenching rains during the month of May, and in particular over the last two weeks. From Houston to Austin to Dallas, torrential one- to two-day rainfall of 4-12 inches has created havoc. In fact, the suburbs of Houston received up to 11 inches of rain in just 24 hours on May 26. According to the state climatologist of Texas, the state has averaged 7.54 inches of rain in May, which is almost an inch higher than the previous record wet month (June 2004).

Combined together, these individual weather events have made for a climate-scaled catastrophe and a serious case of weather whiplash. This region of the United States was suffering from drought conditions for the better part of the last 4 years.  All drought is expected to disappear due to the recent rains.

https://www.climate.gov/news-features/event-tracker/flood-disaster-texas-and-oklahoma