WunderBlog Archive » Category 6™

Category 6 has moved! See the latest from Dr. Jeff Masters and Bob Henson here.

The Amazing Rains of May: Photos and Stats

By: Bob Henson 2:35 PM GMT on June 02, 2015

Now that May has mercifully drawn to a close, and the south-central states are drying out and cleaning up, we can take full measure of what an incredibly, destructively soggy month it was, especially for Texas and Oklahoma. Both states obliterated their rainfall records for any calendar month going back to 1895. While the rains quickly doused a multiyear drought (see Figure 3 below), the flooding killed at least 31 people, with 6 others missing as of Monday night, and inflicted at least $1 billion in damage, according to estimates from the insurance broker Aon Benfield. Below are a few memorable images from the past month—but first, some numbers:

Figure 1. Top-ten wettest months in the statewide averages for Oklahoma and Texas. The May 2015 values are preliminary. Data courtesy Gary McManus and John Nielsen-Gammon, the state climatologists for OK and TX respectively, from a database maintained by NOAA’s National Centers for Environmental Information (formerly the National Climatic Data Center).

As Figure 1 shows, the totals for both TX and OK in May exceeded the previous records by more than 30%, truly a phenomenal outcome. In fact, the gaps between the #1 and #2 outcomes are far larger than the gaps between #2 and #10! Texas state climatologist John Nielsen-Gammon (Texas A&M University) came up with a back-of-the-envelope estimate for how often you would expect such an extremely wet month in his state: about every 2000 years, assuming the climate of the past century were to persist. For more on the science behind recurrence intervals such as this and how they’re produced, see our post from last Saturday. Interestingly, no other single month appears on the top-ten wettest lists for both Texas and Oklahoma—another sign of how unusually widespread and persistent this event was.

The rains of May made weather history on a local scale as well. WU weather historian Christopher Burt assembled the preliminary list below of some cities that notched their all-time wettest months in May, including their periods of record (POR).

Ft. Smith: 19.85” (previous record 15.02”, June 1945; POR began 1882)

Colorado Springs: 8.13” (previous record 8.10”, May 1935; POR began 1894, with some data back to 1871)
La Junta: 7.38” (previous record 6.27”, Aug. 1916; POR began 1910)
Eads: 9.25” (previous record 8.60”, July 2014; POR began 1907)
Ft. Morgan 10.46” * (previous record 9.98”, Apr. 1900; POR began 1896)
(*Ft. Morgan data are from a CoCoRaHS station and not official)

Oklahoma City: 19.48” (previous record 14.66”, June 1989; POR began 1891)
Lawton: 20.47” (previous record 16.67” ,June 2007; POR began 1912)

Wichita Falls, TX: 17.00” (previous record 13.22”, May 1982; POR began 1897)
Childress, TX: 13.21” (previous record 12.05”, May 1941; POR began 1897)

Burt adds: “The wettest location in the Oklahoma Mesonet was Lane, with an amazing 28.17”. If official, this would smash the previous OK state monthly precipitation record of 23.95”, set at Miami in May 1943.”

Bob Henson

Figure 2. Rainfall in May 2015 was far above all previous Mays in the Oklahoma City climatological record, as shown in this trace of cumulative totals achieved day by day. Image credit: Patrick Marsh, @pmarshwx.

Figure 3. The definition of Weather Whiplash: portions of Texas and Oklahoma went from the most extreme category of drought--"Exceptional"--to no drought whatsoever in just four weeks. A five-class improvement in drought in such a short period of time is bound to lead to serious flooding.

Figure 4. Sunlight filtered through clouds and rain casts a copper glow on flooded field near Lubbock, TX. The city saw a spectacular, drought-quenching series of storms in late May, although the month’s 12.12” of rain fell short of May 1941 (12.69”) and September 1936 (13.93”). Image credit: Jason Davis.

Figure 5. In Oklahoma City on May 23, a truck powers its way through high water--and serves a good example of what to avoid when behind the wheel during heavy rain. As little as two feet of water can sweep most vehicles off the road, and it only takes a few inches of water to obscure a road that might be washed out. (Jim Beckel/The Oklahoman via AP.

Figure 6. Canoes replaced motor vehicles on a road near Bear Creek Park in west Houston on May 30. Interpolation from rain gauges suggests that upwards of 13” of rain fell in 24 hours over one part of southwest Houston. Widespread flooding inundated large parts of the urban area. Image credit: AP Photo/David J. Phillip.

Figure 7. In northeastern Oklahoma, water poured through the Robert S. Kerr Lock and Dam along the Grand River on May 30 at the rate of 349,000 cubic feet per second, or about four times the average flow rate over Niagara Falls. Image credit: Tulsa District, U.S. Army Corps of Engineers.

Figure 8. Mike Graf stands on the foundation of his home near Wimberley, TX, on Stone Canyon Street after it was completely swept away by the Blanco River in the flood on Saturday night, May 23. "It's only things," he said. The flooding killed at least 8 people along the Blanco River, with several others still missing, and destroyed dozens of homes in and near Wimberley. Image credit: Jay Janner/Austin American-Statesman via AP.

Figure 9. This campground at Kaw Lake, in north-central Oklahoma near Ponca City, wasn’t getting much use on June 1. Image credit: wunderphotographer CReese.

Figure 10. The calm after the storm: a photo taken on Memorial Day, May 25, after the flooding had peaked at Bastrop, TX. Image credit: wunderphotographer Kiowa63.

Flood Extreme Weather

The views of the author are his/her own and do not necessarily represent the position of The Weather Company or its parent, IBM.

Reader Comments

Quoting 490. Ryan1000:

It's already a 4 according to NHC's latest advisory, 130 mph and 948 mbars. This upgrade also makes Blanca the earliest 2nd major hurricane of any EPac season according to their forecast discussion, let alone the earliest 2nd hurricane of any EPac season period.
I like too see that perfect eye and well its here
EP022015 - Major Hurricane BLANCA

Storm Relative 1 km Geostationary Visible Imagery

Quoting 498. Grothar:

As a P.S. They great flood actually occurred in 5602 B.C. The forecast for that day was partly cloudy skies with a chance of locusts. Who knew?????

Actually, it was a Leap year, so it was 5603 B. C. according to MY abacus,

Quoting 493. LargoFl:

Gro, the one jumping central America is that the one the Euro is seeing down the road?

I think so. Most of the models have been showing this for a few days. I've been looking ahead to see what would make this go straight north, but I still haven't located it. Still looking, though.
kinda surprised Levi hasn't done a new video on his blog.
JeffMasters has created a new entry.
Quoting 468. cytochromeC:

Well, we could always ask the Talking Snake if they are correct.
He hangs out under that Magical Tree with the Rib Woman.

Seriously comrades, do we need creation myths on a science blog? Who said creation is not science? You call this a science blog LOL!
509. jpsb
Quoting 500. cRRKampen:

Of course. In fact, if questions are asked in order te receive answers which question maker uses, I'm even okay with disrespectfully asked questions.
But there is no debate let alone discussion with climate revisionists and I absolutely do not pretend there could be one. And this I spread as education here and there, because the very debate with climate revisionists puts them in the win because for the general public it then always seems there's still discussion about CO2 being a GHG (all climate revisionism denies this fact, implicitly or explicitly).

False, everyone knows CO2 is a greenhouse gas, the amount of forcing that can be attributed to man make CO2 is debated. And also debated is if natural forcings can overwhelm CO2 forcing.
Quoting 456. Misanthroptimist:

Uh-huh. They just forgot to bring their scientific evidence to share with the class. But I'm sure they waved their hands in a most scholarly way. LOL.
When I read "Steven Austin" I though he was referring to Stone Cold Steve Austin... I am disappoint. [Redacted] has repeatedly shown that he is incapable of comprehending scientific methodology and his posting of creationism is concrete evidence of this. Science: Observe phenomena, formulate hypothesis, test hypothesis, peers retest hypothesis, ect... Creationism: Create myth, try to stuff observations into said myth even if it complete and utter [redacted].