Great June Flood, The Sequel (June 24, 2019)

Monday Night Madness: "Great June Flood II" in 2019 Strikes Willacy, Eastern Hidalgo, and Northwest Cameron on June 24th

Overview
Rainfall
Wind Damage
Photos
Radar
Satellite
Hydrographs

It was déjà vu all over again.

Just 367 days after the last of the Great June Flood of 2018 had left its memorable mark on nearly all of the populated Rio Grande Valley, a confluence of atmospheric events came together during the late afternoon and evening of June 24th, 2019, to produce another memorable - and unfortunate - situation for parts of the Rio Grande Valley. This time, the impacted area was smaller and less populated but the results the same. For most of Willacy County's population, the western third of Cameron, and a corner of eastern Hidalgo, the following occurred:

Over a foot of rain fell in about six hours, including a peak total of more than 15 inches near Santa Rosa (Cameron/Hidalgo line)
Hundreds of streets flooded, including 30 Texas-managed highways.
1,188 homes were considered "destroyed" or incurring "major" damage requiring significant repairs. An additional 182 homes sustained "minor" damage or were mildly affected (as of July 10)
Individual Assistance (IA) costs were estimated at $27.6 million. Public Assistance (PA) costs had not yet been factored in (July, 2019)
Total damage is likely to range from $50 to $100 million or more when all estimates have been received. Final estimated may not be known until late 2019.
More than 100 persons were evacuated to safe high ground from dozens of homes threatened by 2 or more feet of water in several locations in each county
At least 45,000 private and public utility power customers were without power at the peak of the storm
Estimated 65 to 75 mph winds caused at least five poorly built mobile homes to be rolled or demolished in eastern Hidalgo County
Lightning struck a wind turbine and set it ablaze in Willacy County

New daily rainfall records were set at most available Rio Grande Valley climate recording locations. These included:

Raymondville, with 9.7 inches* (prior: 1.83 inches in 1922; new June daily record - prior: 6.23 inches on 6/21/1993)
Weslaco, with 6.95 inches* (prior: 3.72 inches in 1951)
Harlingen, with 6.29 inches* (prior: 2.23 in 1926; new June daily record - prior: 5.89 inches on 6/20 2018)
McAllen, with 3.30 inches (prior: 1.83 inches in 1973)
Edinburg, with 2.49 inches* (prior: 1.36 inches in 2014)
Brownsville, with 2.06 inches (prior: 2 inches in 1920)

*Based on 7 AM to 7 AM records

These single day rainfall totals, except for Brownsville and Edinburg, were above the monthly averages for June. For Harlingen, and Weslaco, these values were around three times the monthly average, and more than four times the monthly average for Raymondville.

Cities and towns with the most impact included:

Raymondville (Willacy Co) - The entire north half of the city's streets were flooded, with dozens if not more than 100 homes and business taking on inches to feet of water
Sebastian (Willacy Co) - All neighborhood streets were flooded due to rainfall and drainage issues through the 25th and beyond
Harlingen/Primera (Cameron Co) - Frontage roads, businesses along them, and neighborhoods - all north of Interstate 2 - had multiple flood issues due to rainfall and overwhelmed drainage systems
La Feria through Mercedes (Cameron/Hidalgo Line) - Same situation as portions of northwest Harlingen. This was the primary area of overlapping impacts similar to the June 2018 event, just one year later.
Elsa through Monte Alto colonias, occurred (see Wind Damage tab for more). At least five residences were demolished, one rusting grain silo tower collapsed, and dozens of trees were uprooted and numerous tree limbs blown down. Flooding rains and poor drainage left at least 4 feet of water in at least one neighborhood, requiring evacuations.

In addition to the neighborhood flooding, the location and intensity of the rainfall poured into Arroyo Colorado, with quite a bit of outflow into the Rio Grande as well.

The Arroyo Colorado crested at 22.67 feet, the highest level since June 2018 and the fourth highest on record. It was the second time in two years that only runoff from rainfall caused the rises. The high water flooded parks and other activities inside the levee.
The Rio Grande near San Benito was forecast to crest near 44 feet and near Brownsville, up to 14 feet, as of this writing.

Different Situation, Similar Result

Unlike the Great June Flood of 2018, the atmospheric setup couldn't have been any more different. This time, the situation - one that had been a persistent feature since April - was setup by yet another energy wave that moved through north central and east Texas, and spawned another round of severe weather (wind/hail) on Sunday, June 23rd. This was the initial feature that set the table to trigger the crazy...and scary...events of June 24th:

Ingredient 1: A thunderstorm "system" in southeast Texas. This system, moving to the right of the mean atmospheric flow, rolled through southeast Texas, including Houston/Galveston, on its way to the Gulf by daybreak Monday. It would propagate on its own momentum into the western Gulf, still hugging the Texas coast, with a slow but steady movement toward the Coastal Bend.
Ingredient 2: Southeast to east "inflow" and daytime heating = Supercell. Incredibly persistent heat and humidity across south Texas combined with colliding southeasterly flow with the northerly winds along the boundary began new thunderstorm develop near Kingsville a little after noon on the 24th. That cell would continue to feed on moisture inflow and the turning winds to produce a high-precipitation supercell thunderstorm in Kenedy County.
Ingredient 3: Multiple colliding boundaries and supercell slowdown. Between 5 and 6 PM, as the supercell storm was still producing strong to destructive winds and pockets of large hail, outflow boundaries propagating west and southwest fed on the near record heat and oppressive humidity to produce expansive clusters of storms that spread quickly into Hidalgo and Starr County. Other boundaries from the old main line in the Gulf, and new storms in northern Mexico, fed the beast. At the same time, the entire system slowed before reaching the Rio Grande as evening approached and the earlier boundaries ran out of momentum.
Ingredient 4: Coalescence and Upper Level Assistance. The development of mesoscale high and low pressure couplets along with favorable upper level winds allowed for a broad circulation to form, centered near the triple county lines of Hidalgo, Willacy, and Cameron, by mid evening of the 24th. Pulsing storms within the circulation maintained intense rainfall, up to the rate of 3 inches per hour, from 8 PM to midnight - which completed the transition from a mixed severe weather and flood event to a predominant flood event that spread into all of western Cameron County while continuing over western Willacy and far eastern Hidalgo County.

Additional details will be added to this report into July as more data are received from emergency management and other partners following damage assessments.

Corrections, additions, and/or deletions to the list below may occur as new information arrives.

Public Information Statement
National Weather Service Brownsville TX
1034 AM CDT Tue Jun 25 2019

...RAINFALL AMOUNTS FROM A HEAVY RAIN EVENT ON JUNE 24TH AND 25TH...

Location                     Amount    Time/Date       Provider             

...Texas...

...Cameron County...
Harlingen 4.7 WSW            11.60 in  0200 AM 06/25   COCORAHS             
Harlingen 3.1 WSW            11.40 in  0700 AM 06/25   COCORAHS             
Harlingen 4.4 W              11.12 in  0700 AM 06/25   COCORAHS             
Harlingen 6.2 WSW            11.03 in  0700 AM 06/25   COCORAHS             
Harlingen 4.2 W              11.00 in  0700 AM 06/25   COCORAHS             
Harlingen 4.7 W              10.96 in  0700 AM 06/25   COCORAHS             
Harlingen 0.4 N              8.60 in   0800 AM 06/25   COCORAHS             
Harlingen Co-Op              6.29 in   0700 AM 06/25   COOP                 
Brownsville 3.5 N            4.52 in   0800 AM 06/25   COCORAHS             
Lozano 1.4 S                 4.50 in   0700 AM 06/25   COCORAHS             
Brownsville 1.7 NNE          4.18 in   0700 AM 06/25   COCORAHS             
Brownsville 4.1 ENE          4.16 in   0800 AM 06/25   COCORAHS             
Brownsville 0.1 SSE          4.05 in   0600 AM 06/25   COCORAHS             
Brownsville 2.8 N            3.92 in   0800 AM 06/25   COCORAHS             
Brownsville 1.5 WNW          3.73 in   0700 AM 06/25   COCORAHS             
Brownsville 0.4 WSW          3.25 in   0655 AM 06/25   COCORAHS             
Brownsville 2.2 W            3.14 in   0600 AM 06/25   COCORAHS             
Los Fresnos 0.3 NE           3.12 in   0700 AM 06/25   COCORAHS             
Brownsville 6.4 SE           2.70 in   0800 AM 06/25   COCORAHS             
Los Fresnos 2.1 NNE          2.64 in   0558 AM 06/25   COCORAHS             
Laguna Atascosa              2.39 in   0922 AM 06/25   RAWS                 
San Benito 7.8 E             2.38 in   0700 AM 06/25   COCORAHS             
Brownsville 6.4 WNW          2.27 in   0740 AM 06/25   COCORAHS             
Rancho Viejo 0.7 E           2.21 in   0700 AM 06/25   COCORAHS             
Laguna Vista 0.3 N           1.97 in   0700 AM 06/25   COCORAHS             
Laguna Vista                 1.43 in   1015 AM 06/25   CWOP                                 

...Hidalgo County...           
Santa Rosa 3 WNW Co-Op       15.20 in  0700 AM 06/25   COOP
Weslaco Co-Op                6.95 in   0726 AM 06/25   COOP                 
Mission                      3.46 in   1015 AM 06/25   CWOP                 
McAllen 3.5 N                3.20 in   0700 AM 06/25   COCORAHS             
Mission 1.9 ENE              3.20 in   0730 AM 06/25   COCORAHS             
Edinburg 2.4 N               3.08 in   0800 AM 06/25   COCORAHS             
Mcallen                      2.83 in   1020 AM 06/25   AWS                  
McAllen 2.7 NNE              2.65 in   0800 AM 06/25   COCORAHS             
Edinburg Co-Op               2.49 in   0700 AM 06/25   COOP                 
Mission                      2.37 in   1015 AM 06/25   CWOP                 
4 W Edinburg                 2.35 in   1020 AM 06/25   AWS                  
Mcallen Co-Op                2.20 in   0600 AM 06/25   COOP                 
Linn-San Manuel              2.19 in   0946 AM 06/25   RAWS                 
La Joya 11.1 N               1.90 in   0600 AM 06/25   COCORAHS             
San Manuel Co-Op             1.74 in   0700 AM 06/25   COOP                 
La Joya Co-Op                1.65 in   0747 AM 06/25   COOP                 
Mission 9.6 N                1.38 in   0700 AM 06/25   COCORAHS                            

...Starr County...
Falcon Lake                  2.05 in   1011 AM 06/25   RAWS                 
Rio Grande City 17.7 NE      1.35 in   0600 AM 06/25   COCORAHS             

...Willacy County...
Raymondville Co-Op           9.70 in   0700 AM 06/25   COOP
Port Mansfield Co-Op         2.53 in   0700 AM 06/25   COOP                 
Port Mansfield 1.1 SE        2.53 in   0700 AM 06/25   COCORAHS             
            

Observations are collected from a variety of sources with varying
equipment and exposures. We thank all volunteer weather observers 
for their dedication. Not all data listed are considered official.


PUBLIC INFORMATION STATEMENT
NATIONAL WEATHER SERVICE BROWNSVILLE TX
947 PM CDT Tue Jun 25 2019

...NWS DAMAGE SURVEY FOR 06/24/2019 THUNDERSTORM WIND EVENT...

.MONTE ALTO STRAIGHT LINE WIND EVENT...

ESTIMATED PEAK WIND:    65 to 75 MPH
PATH LENGTH (STATUTE):  8.00 MILES
PATH WIDTH (MAXIMUM):   3.75 MILES
FATALITIES:             NONE
INJURIES:               NONE

START DATE:             JUN 24, 2019
START TIME:             0713 PM CDT
START LOCATION:         1.50 MILES NORTH OF MONTE ALTO
START LAT/LON:          26.3999/-97.9612

END DATE:               JUN 24, 2019
END TIME:               0730 PM CDT
END LOCATION:           1.75 MILES NORTHEAST OF SAN CARLOS
END LAT/LON:            26.3181/-98.0460

A SEVERE THUNDERSTORM PRODUCED SPORADIC STRAIGHT LINE WIND DAMAGE
FROM MONTE ALTO TO PORTIONS OF NORTH ELSA DURING THE EVENING OF
JUNE 24TH. STORM MOTION WAS SOUTHWEST AND BEGAN SNAPPING LARGE
TREE LIMBS AND UPROOTING A FEW TREES ON THE EAST SIDE OF MONTE
ALTO. WINDS ALSO CAUSED A FREE STANDING METAL TOWER TO COLLAPSE.
AS THE STORM MOVED SOUTHWESTWARD, LARGE SWATHS OF SUGAR CANE WERE
NOTICEABLY BENT TOWARDS THE GROUND. FURTHER WEST, TWO POORLY 
CONSTRUCTED MOBILE HOMES WERE COMPLETELY DESTROYED AND ANOTHER WAS
ROLLED ON ITS SIDE. CLOSER TOWARDS ELSA OFF OF MONTE CRISTO RD 
WERE OVER A DOZEN WOODEN POWER POLES SNAPPED ACROSS N MILE FIVE 
1/2. IN ADDITION, SOME METAL SHEET ROOFING WAS TORN OFF OF A 
NEARBY HOME AND A STORAGE SHED HAD CONSIDERABLE DAMAGE TO WALLS 
AND ROOFING. CONSIDERING BUILDING MATERIALS AND CONDITION, PEAK 
WIND SPEEDS WERE ESTIMATED AT 65 TO 75 MPH. SPECIAL THANKS TO 
HIDALGO COUNTY EMERGENCY MANAGEMENT FOR THEIR ASSISTANCE.

NOTE:
THE INFORMATION IN THIS STATEMENT IS PRELIMINARY AND SUBJECT TO
CHANGE PENDING FINAL REVIEW OF THE EVENT AND PUBLICATION IN NWS 
STORM DATA.

For a map, specific survey details, and photos of wind damage along the general path of the straight line winds in eastern Hidalgo County, click the image below. Download Google Earth to interact with the map after clicking