More locally heavy rainfall is forecast for flood-weary parts of Texas, Oklahoma and Louisiana, including the Houston metro area through at least Wednesday, ahead of a slow-moving low pressure system pushing from the Rockies in the nation's midsection.
Map showing the heaviest rainfall totals in the Houston area in the 24 hours through Monday morning.(LATEST NEWS: Destructive, Deadly Flooding Hits Houston)
Major flooding has been reported on bayous, creeks and rivers in the Houston area, including: White Oak Bayou at Houston, Cypress Creek near Westfield and Hockley, West Fork of the San Jacinto River near Humble.
Below are more details on the severe weather and flood threats the next few days. At the bottom of this article you can find a full recap on the severe weather caused by this same storm system since Friday.
Flood Threat Forecast
Tuesday- Clusters of t-storms with locally heavy rain and additional local flash flooding are possible in parts of west, central and east Texas into Louisiana.
- A separate line of t-storms may move out of the Texas panhandle into Oklahoma, southern Kansas and north Texas overnight.
- This line of storms should generally move east, instead of completely stall out, however, the southern end of that line may move more slowly, giving rise to a threat of flash flooding in parts of southern Oklahoma and north Texas.
- A few severe t-storms are possible in west-central Texas, but the overall severe threat is low, with hail and damaging winds the main threats.
Current Radar with Watches and Warnings
- Clusters of slow-moving thunderstorms are again expected in east and southeast Texas and Louisiana, including the Houston metro area.
- While not as heavy as Monday's event, additional flash flooding is possible, and locally heavy rainfall may slow the fall of already flooded rivers, creeks and bayous in southeast Texas.
- Once again, an isolated severe t-storm is possible with a brief strong wind gust and hail possible.
- Wednesday night, some t-storm clusters are possible from the Texas panhandle into Oklahoma and central Texas
- Other areas of locally heavy rain are possible farther north into the mid-Mississippi Valley.
Flood Alerts
- Clusters of thunderstorms should sweep from the Red River southeastward toward the Texas and Louisiana Gulf Coast Thursday.
- Drier weather will finally arrive by Friday behind a cold front.
The map below is a general view of the area where we're expecting the heaviest rain through Thursday.
Rainfall Outlook Through Thursday
Flood Recap
Impressively, April 18 was the second wettest calendar day on record for official reporting stations in Houston, dating to 1888, with 9.92 inches of rain measured at Bush Intercontinental Airport. Only one other calendar day was wetter, June 26, 1989 (10.34 inches). This was also almost exactly three times the average rain for the entire month of April (3.31 inches).
Edgar Peneda inspects section of 290 at Huffmeister that collapsed during heavy flooding @HoustonChron #houstonflood
(FLASHBACK: Massive Louisiana March 2016 Flood)
2nd wettest Apr. day Mon. in Shreveport (6.03"). Last month, they had their top 2 wettest Mar. days. (3/8 & 3/9).
Incredibly, this was just under 10 inches higher than the crest there during the Allison flood of June
Top 5 Crests on Record: Cypress Creek Near Cypress, Texas
Records date to at least 1979. Flood stage is 122 feet.
| 1 | October 18, 1994 | 127.60 |
| 2 | April 19, 2016 | 127.52 |
| 3 | June 9, 2001 | 126.71 |
| 4 | October 19, 1998 | 126.5 |
| 5 | April 29, 2009 | 125.23 |
2001, though it should be noted metro area rainfall totals during Allison were up to double what they were in this event.
(FLASHBACK: May 2015 Houston Area Flood)
Other mainly minor to moderate river flooding was observed in parts of central and north Texas into southern Oklahoma. East Cache Creek near Walters, Oklahoma, surged into major flood status early on April 19, reaching levels that would put some county roads under 5-6 feet of water, according to the National Weather Service.
In some parts of the High Plains, the average rainfall for April was doubled in just a couple of days this past weekend. This includes Dodge City, Kansas, which picked up 4.98 inches of rain Saturday into Sunday, more than doubling their April average of 1.82 inches. Northeast of Dodge City in Ellis County, a few roads were washed out by flooding.
Here is a list of notable rainfall totals by state through Monday evening:
- Kansas: 6.52 inches near Elkhart; 4.98 inches in Dodge City
- Louisiana: 6.03 inches at Shreveport Regional Airport
- Nebraska: 6.25 inches near Riverdale; 5.50 inches in Kearney
- Oklahoma: 7.08 inches in Frederick; 6.13 inches in Tipton; 3.44 inches in Okla. City
- Texas: 10-20 inches on north and west side of the Houston metro; over 10 inches of rain was also reported west of the Austin metro in Fayette county
What's Causing the Heavy Rain?
Sometimes, winds at jet-stream level don't simply flow generally west to east (in the northern hemisphere), but rather take large north-south (or south-north) meanders. When this happens, weather systems producing rain or snow slow down.
Upper-level
pattern forecast for Sunday, April 17, 2016, featuring an omega block
in the East, trapped low in the Rockies, and deep moisture into the
Plains states.(MET 101: "Omega Block" Brings Welcomed Warm-Up)
With high pressure both to the northwest and northeast of the stuck low, there's nowhere for the closed low to go fast.
On the east side of that swirling, slow-moving low, deep moisture is in place in the central states.
In general, the slower the trapped upper low moves, the greater the potential for heavy rain over the same areas over multiple days.
This stagnant pattern with a deep plume of moisture in place is a prime setup for flooding rainfall, even despite parts of the Plains being rather dry, recently (more on that below).
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