Texas and Oklahoma Set All-Time Record Wet Month; Other May Rain Records Shattered in Arkansas, Nebraska

State climatologist Gary McManus from the Oklahoma Climatological Survey calculated the May rainfall total averaged over all Sooner State reporting stations - 14.40 inches - clobbered the previous record wet month, set in October 1941 (10.75 inches).

Not to be outdone, Texas has picked up a statewide average of 8.81 inches in May, crushing the previous record wet month of June 2004 during which a statewide average of 6.66 inches of rain fell, according to the Office of the State Climatologist at Texas A&M University.

"It has been one continuous storm after another for the past week to 10 days in several regions of the state," said Dr. John Nielsen-Gammon, Texas state climatologist in a press release Wednesday. "Spring is usually wet, but not this wet."

At one time, more than 170 locations in the central and southern Plains reported river flooding, the majority of which were in Texas, Oklahoma, Louisiana, Arkansas, eastern Kansas and Missouri.

Many cities set a record wettest May or month including Dallas-Ft. Worth, Wichita Falls, Oklahoma City and Corpus Christi.

May's Incredible Records

From Colorado and Nebraska to Oklahoma, Texas and Arkansas, several cities have seen one of their wettest Mays on record. Here's a final look at May's numerous records.

Amarillo, Texas – 9.29 inches of rain had fallen, making it the second-wettest May on record. The all-time record is 9.81 inches in May 1951.

Austin (Camp Mabry), Texas – Extremely heavy rainfall on May 25 dumped 5.20 inches of rain at Camp Mabry, lifting Austin to its wettest May on record. The May rain tally was 17.59 inches, making it by far the wettest May on record, topping the old record of 14.10 inches in May 1895. It's also the third wettest month on record. September 1921, with 20.78 inches, leads the pack for the city's wettest month.

Across town, Austin Bergstrom International Airport logged its second-wettest May since records began in 1943, tallying 13.44 inches, exactly a quarter-inch shy of the May record set in 1965.

Brownsville, Texas – While most other areas of Texas finally caught a break, Brownsville saw torrential downpours totaling 3.50 inches on the final day of May, sending the southernmost large city in Texas to a new May rainfall record of 9.72 inches. The previous May record had been 9.12 inches in 1982.

Because of the many hurricanes that have hit the region over the decades, this month was easily outranked by a slew of Septembers and Octobers on the year-round list. May 2015 was only the 31st-wettest month overall for Brownsville, counting the entire calendar.

Childress, Texas – Despite a population of just 6,000 or so, this northwest Texas town is one of the National Weather Service's official "first-order" climate and weather observation sites. And it had never observed weather quite like that of this May. As of late May 31, the monthly rainfall total stood at 13.21 inches; this will replace June 1941 (12.05 inches) as the city's wettest month ever recorded.

Corpus Christi, Texas – Rainfall in May 2015 was 14.32 inches, which is well beyond the previous May record of 10.44 inches that was set in 1941. A total of 4.56 inches fell on May 21 to clinch the record. Amazingly, just nine days prior, exactly 4.56 inches of rain also fell in the city. May 12 and May 21 are now tied as the third-wettest May days in the city's weather records.

According to weather.com senior meteorologist Nick Wiltgen, May 2015 now exceeds Corpus Christi's total rainfall for the entire drought-parched year of 2011, which was only 12.06 inches.

Dallas-Fort Worth, Texas  – 16.96 inches of rain fell at Dallas-Fort Worth International Airport, smashing the old May record of 13.66 inches in 1982.

The wettest month on record in the Metroplex is 17.64 inches in April 1922. May 2015 was the single wettest month in the Metroplex since April 1942 -- 16.97 inches.

It is also the second wettest spring (March through May) on record with 25.05 inches. The current record is 29.01 inches set in 1957.

For purposes of recordkeeping, the National Weather Service considers DFW Airport data since 1974 to be a continuation of rainfall records kept in Fort Worth from 1898 to 1974.

Dallas, Texas – The official National Weather Service observation site for Dallas proper is currently Love Field, where 14.98 inches of rain was measured in May. That broke the May record of 13.74 inches set in 1957. It ranks third among all months, behind October 1981 (16.05 inches) and April 1966 (15.40 inches).

Del Rio, Texas – This border city along the Rio Grande west of San Antonio came very close to a new May rainfall record, logging 10.17 inches. This ranks third among all Mays, just behind 2010 (10.45 inches) and 1957 (10.23 inches).

Houston, Texas – 14.17 inches of rain had fallen at Bush Intercontinental Airport on the city's north side, putting it in fifth place among the city's wettest Mays. The record wet May there is 15.87 inches in 1907. 

Lubbock, Texas – 12.12 inches of rain fell in May, making it Lubbock's second-wettest May on record. This was a bit short of the 12.69 inches needed to claim the title for the wettest May. According to the National Weather Service, the last time it rained 8 inches or more in a month in Lubbock was September 2008 with 8.70 inches.

It is also the third-wettest month in the city, behind May 1941 (12.69 inches) and September 1936 (13.93 inches), oddly a Dust Bowl year.

San Angelo, Texas – 9.12 inches of rain in May 2015 was their second wettest May, behind only May 1987's 11.24 inches. 

It was also the fifth wettest month in the city. Incredibly 27.65 inches fell in a Dust Bowl month -- September 1936 -- easily their wettest month.

According to the National Weather Service in Norman, Oklahoma, May 2015's rainfall in Wichita Falls exceed that from the previous six Mays combined - 13.41 inches.

Oklahoma City – Oklahoma's capital reached a month-to-date total of 14.53 inches at 5:56 p.m. CDT on May 23, breaking its all-time May rainfall record of 14.52 inches in 2013. Only 21 minutes later, the city broke its June 1989 record of 14.66 inches to become the wettest month in Oklahoma City history. An extremely heavy downpour followed with more than 2 inches of rain.

Oklahoma City's new all-time record monthly rainfall total cracked the 19-inch mark May 27. The final May total was 19.48 inches. This is more than the average precipitation over a five-month period from March through July (18.68 inches).

Tulsa, Oklahoma – The city's May total is 14.77 inches was their second-wettest May on record. The record of 18.00 inches in May 1943 has withstood this year's strong challenge.

Fort Smith, Arkansas – This western Arkansas city has now recorded its wettest month in history with 19.85 inches of rain in May 2015. This crushed the previous record of 15.02 inches in June 1945.

Baton Rouge, Louisiana – Louisiana's capital city picked up 11.17 inches of rain in May, their third wettest on record. Only 1989 (14.67 inches) and 1946 (12.34 inches) featured wetter Mays, there.

Wichita, Kansas – The largest city in Kansas topped the 10-inch mark May 23 thanks to heavy rainfall. May 2015 - 11.77 inches - was the second-wettest May on record in the Air Capital city, second only to 13.14 inches in 2008.

Lincoln, Nebraska – 10.90 inches of rain in May 2015 was the wettest May in the Nebraska capital, topping the previous wettest May record of 10.72 inches set in 1903.

Valentine, Nebraska – 7.12 inches of rain ranked as the third-wettest May. The record wettest May of 8.96 inches was set in 1962.

Colorado Springs, Colorado – 8.13 inches of rain at Colorado Springs Municipal Airport was their wettest May on record. The previous wettest May was in 1935 when 8.10 inches was recorded. Interestingly, several co-operative and volunteer observation sites only a few miles west of the airport picked up 10 to 14 inches of rain during the month.

Twenty-three days had measurable precipitation (.01 inch or greater) at the Colorado Springs airport; that is an all-time record for any month, crushing the record of 21 days in August 1927. Seven other days had a trace of precipitation.

Pueblo, Colorado – A total of 5.55 inches of rain topped the previous wettest May from 1957 when 5.43 inches was measured.

Every day from May 5 through May 30 – that's 26 straight days – brought at least 4 inches of rainfall to at least one location in the state of Texas, according to CoCoRaHS, the Community Collaborative Rain, Hail and Snow Network. At least 100 of the volunteer network's 1,699 reporting sites in Texas have recorded at least 10 inches of rain this month. The highest rain total came in from an NWS cooperative observer east of Gainesville, near Lake Texoma along the Oklahoma-Texas border with a total of 28.90 inches.

Oklahoma has also taken a drenching in May, with totals topping 10 inches across much of the southern half of the state. Lane, Oklahoma has seen 28.17 inches of rain since May 1 according to the Oklahoma Mesonet. A CoCoRaHS site northeast of Norman has reported 26.57 inches of rain in May 2015.

Among other states in the May rainy zone, top month-to-date totals by state include 24.46 inches near Big Fork in west-central Arkansas; 17.62 inches near Ruston in northern Louisiana; 13.83 inches in the Ivywild neighborhood of Colorado Springs, Colorado; 13.03 inches near Fairbury in southeast Nebraska; 15.33 inches 5.5 miles southeast of Topeka, Kansas; and 15.07 inches in Shell Knob in southwestern Missouri.

The 12 National Weather Service offices located in Texas and Oklahoma had issued a combined 594 flash flood warnings in May. In all of 2014, they only issued 497 such warnings.

Southern Plains Flooding Recap

Overnight Thursday into early Friday, more flash flooding pounded the Dallas-Ft. Worth metroplex, stranding cars and flooding apartments.

(MORE: Dallas-Ft. Worth Flooding May 28-29)

More than 10 inches of rain fell in parts of Houston late Memorial Day night into the following day, causing widespread flash flooding in the city. A flash flood emergency was issued by the National Weather Service for much of the night.

Over the Memorial Day weekend, catastrophic flash flooding overnight Saturday into early Sunday flooded hundreds of homes in Hays County, Texas, including areas near Wimberley and San Marcos.

(RECAP: Catastrophic Flash Flooding Texas, Oklahoma | Jaw-Dropping Houston Flood Images)

The National Weather Service in Corpus Christi, Texas, says flooding is likely to continue for weeks along the Nueces River just west of Corpus Christi. The flooding is affecting a stretch downstream of the Wesley Seale Dam, which impounds Lake Corpus Christi.

Lake Texoma, a reservoir impounding the Red River on the Texas-Oklahoma border, was at its highest level on record as of Sunday morning at 645.65 feet.

Downstream, the Red River is expected to crest the first week of June at levels comparable to the May 1990 flood in Shreveport, Louisiana, potentially flooding some streets in Bossier City and north Shreveport.

According to the National Weather Service, thanks to the number of full reservoirs and tributaries upstream, the Red River may remain high through at least the end of July in the Ark-La-Tex region.

The rising Wichita River prompted evacuations of parts of the east side of Wichita Falls, Texas last Wednesday night and Thursday morning. However, the river crested about 2 feet lower than original forecasts and about 3 feet below the late June 2007 record. 

PHOTOS: Southern Plains Flooding, May 2015