SLIDE 1 Cynthia Palmer Science and Operations Officer National Weather Service – Shreveport Special Thanks to Craig S. Ross, Tony Hurt, & Julianna Glinskas
SLIDE 2 Overview
Two periods of flooding along the Red River
Late Spring – Early Summer (May 10th – July 5th) Late Fall – Early Winter (November 26th – January 7th)
Rainfall
Placement:
North Central Texas and South Central Oklahoma (May/Jun) Northeast Texas and Southeast or East Oklahoma (Nov/Dec)
Quantity
Percent of Normal: 150-600%
SLIDE 3
Red River Basin
SLIDE 4 May Rainfall Totals
Denison Dam Pecan Point Hugo Lake
Record Rainfall:
- Widespread 10+ inches over the Red
River basin.
- Broad area of 20+ inches upstream of
Lake Texoma and Hugo Lake.
- Percent of Normal: 200-600%
- Wettest May on record for TX and OK.
SLIDE 5 June Rainfall Totals
Denison Dam Pecan Point Hugo Lake
Percent of Normal: 150-600% upstream of Denison Dam
SLIDE 6 Lake Texoma
Lake Texoma Stats:
conservation pool until the end of April.
reservoir filled.
- Crested the dam’s spillway
(640 ft.) twice this spring/summer.
- May 24th
- June 18th
- Broke its record highest
elevation with 645.72 ft. on May 29th.
Courtesy of USACE
SLIDE 7 Discharge from Lake Texoma and Hugo Lake
Courtesy of Tony Hurt
SLIDE 8 Hydrograph for Pecan Point near DeKalb, TX – Spring/Summer Flood
Observed Crest June 2 – 35 ft. First Flood Warning Issued May 8 – 11.42 ft. Observed Crest June 25 – 32.44 ft.
Major Flood Stage Moderate Flood Stage Minor Flood Stage Action Stage
First Forecast within 6 inches of observed crest May 27 – 33.5 ft. Forecast 34.5 ft. First Forecast within 6 inches of observed crest June 19 – 25.7 ft. Forecast 33 ft.
Date River Stage in Feet {7 days} {6 days}
SLIDE 9
Thanks to TXKToday.com
SLIDE 10
Hydrograph for Index, AR – Spring/Summer Flood
SLIDE 11
Hydrograph for Fulton, AR – Spring/Summer Flood
SLIDE 12 Arkansas Flood Pictures – Red Still Rising on May 31st
Hwy 71,AR Fulton, AR
SLIDE 13
Hydrograph for Shreveport, LA – Spring/Summer Flood
SLIDE 14
Flooding in Shreveport/Bossier City
SLIDE 15
Flooding in Shreveport/Bossier City
SLIDE 16
How has the Red River changed in Downtown Shreveport since 1990?
SLIDE 17
Hydrograph for Coushatta, LA – Spring/Summer Flood
SLIDE 18
Bayou Pierre/Coushatta Flooding
SLIDE 19
Hydrograph for Grand Ecore, LA – Spring/Summer Flood
SLIDE 20
Flood Fight in Natchitoches
SLIDE 21 Spring/Summer Flood Summary
Rain fell nearly all up stream of Lake Texoma and Lake
Hugo.
Dension Dam spilled over the uncontrolled spillway
twice
Prolonged crest ranged between 48 and 72 hours at all
gauges .
Pecan Point stayed above flood stage for 55 days (May
10th – July 4th).
Grand Ecore stayed above flood stage for 50 days (May
18th – July 6th).
SLIDE 22 How does this Spring/Summer Flood Compare to Past Floods?
First major flood along the Red River since 1990. First major flood since the Red River Waterway was
completed.
Second worst flood at Grand Ecore. Third worst flood:
At Pecan Point, and nearly eclipsed the May 1908 Flood,
cresting at 35 ft on June 2nd.
At Index. At Coushatta.
Ranked 18th for Fulton. Ranked 25th for Shreveport. Worst flood in 70 years.
SLIDE 23 Impacts – Late Spring/Early Summer
Thousands of acres of pasture and farm land were
flooded.
Hundreds of livestock had to be evacuated. Bank erosion was extreme. The US Highway 259 , Highway 8, and Highway 71 bridges
were closed over the Red River, and Highway 37 bridge over the Red River was threatened.
A number of structures and homes suffered damage. Several county roads, culverts, and bridges needed repair.
$74,000,000 reported in damages to the NWS.
Estimated over $100,000,000 total.
SLIDE 24 November Rainfall Totals
Pecan Point Denison Dam Hugo Lake
Percent of Normal: 200-400%
SLIDE 25 December Rainfall Totals
Denison Dam Pecan Point Hugo Lake
Percent of Normal: 150-600%
SLIDE 26
Hydrograph for Pecan Point near DeKalb, TX – Fall/Winter Flood
SLIDE 27
Hydrograph for Shreveport, LA – Fall/Winter Flood
SLIDE 28
Hydrograph for Shreveport, LA – Fall/Winter Flood
SLIDE 29
Hydrograph for Coushatta, LA – Fall/Winter Flood
SLIDE 30
Hydrograph for Grand Ecore, LA – Fall/Winter Flood
SLIDE 31 Fall/Winter Flood Summary
Rain fell further east, with more breaks between systems. Rain fell in the uncontrolled sections and tributaries of the Red
River.
Comprised of 3 separate crests for Pecan Point.
Nov 26th – Dec 3rd (Tied for the 9th worst flood) Dec 16th – Dec 18th Dec 25th – Jan 6th (Tied for the 9th worst flood)
Not all points along the Red River reached flood stage. Impacts:
Record Pool Stage on Broken Bow Lake (629.47 ft on December
28th).
Thousands of acres of pasture and farm land were flooded. Livestock had to be evacuated.
SLIDE 32 Rainfall Comparison Summary
Denison Dam Hugo Lake Pecan Point Denison Dam Hugo Lake
May Rainfall November Rainfall
- Widespread 15 to 20+ inches fell
upstream of Lake Texoma and Lake Hugo. (Percent of normal: 300-600+)
- Widespread 10 to 15 inches fell
mainly downstream of Lake Texoma and Lake Hugo. (Percent
Rainfall axis shifted east during the fall and winter.
Pecan Point
SLIDE 33 El Nino Winter Climatology & Current Anomaly by Region
Typical January through March Weather Anomalies and Atmospheric Circulations during a Moderate to Strong El Nino.
SLIDE 34 Sea Surface Temperatures Anomalies
- Strong El Nino conditions continue across the Equatorial Pacific.
- November to January ONI (2.3) ties 1997/98 for the largest November to
January value, and likely the peak of this El Nino.
- El Nino should gradually weaken through the spring, transitioning to ENSO
neutral during the late spring and early summer.
SLIDE 35 Rainfall Anomalies
Since October 1, 2015 Since January 1, 2016
SLIDE 36 Shreveport Monthly Normals (1981- 2010)
Shreveport 2015: 65.26 inches (51.41 inches normal)
SLIDE 37
Outlooks for March – May
SLIDE 38
Outlooks for April – June
SLIDE 39 Lower Red River Basin – Where are we right now?
Conservation Pools Flood Control Pools
SLIDE 40
Where are we now?
SLIDE 41 What does this mean for our upcoming spring and summer?
The Red is still running on the high, because of
reservoir releases at Lake of the Pines and Lake Wright Patman.
Rainfall could cause additional flooding along the Red
River through the spring.
Tropical systems this summer could also cause
additional flooding.
Prepare for high water to continue.
SLIDE 42
