Across already very saturated grounds, a slow moving line of thunderstorms moved into Harris County from central Texas during the evening hours of the 25th. Very heavy rainfall began in the mid evening hours across the northern portions of the county, while additional thunderstorms developed over central Fort Bend County and moved into Harris County from the southwest. A period of thunderstorm cell training occurred from around 10 PM to 1 AM from Fort Bend County into north-central Harris County where the cells merged with the line of storms moving southward from northern Harris County. Thunderstorm cell mergers continued over central and southwest Harris County for several hours resulting in widespread significant flooding. The Houston/Galveston National Weather Service Office issued their first ever Flash Flood Emergency for this event. The area's worst flooding was focused across the western portion of Harris County from the northwest side of the City of Houston to Addicks to Sharpstown to Richmond in central Fort Bend County. Hundreds of water rescues (mainly motorists stranded on area freeways and roadways) were performed by various agencies during the height of the rainfall. After daylight on the 26th, the Houston Fire Department responded to many requests for assistance of residences in flooded homes. Seven fatalities were directly related and one additional fatality was indirectly related to the flooding. Three fatalities resulted from the capsizing of a Houston Fire Department rescue boat in Brays Bayou and the other four were all flooded vehicle related. Rainfall totals averaged 3 to 4 inches across much of Harris County with totals of 4 to 6 inches from Humble to Jersey Village to Katy, and then eastward to Galveston Bay. Rainfall totals of 8 to 10 inches were recorded on the northwest side of the City of Houston southwest to Sugar Land. A maximum rainfall accumulation of 11 inches was recorded at Brays Bayou and Beltway 8. A CoCoRaHS observer 6.2 miles west of Downtown Houston recorded 10.03 inches of rainfall. Another observer 3.4 miles northeast of Richmond in Fort Bend County recorded 11.88 inches of rainfall. Maximum rainfall rates included 4.8 inches in one hour, 8. 3 inches in three hours, and 10.1 inches in six hours. The combination of the heavy rainfall and associated overflow of area creeks, rivers and bayous caused flood damage to thousands of homes and close to 100 commercial buildings.

Flash Flood in GRIMES, TEXAS
From 25-MAY-15 18:15:00 to 25-MAY-15 20:00:00 (CST-6)
Location: NAVASOTA MUNI ARPT
Flood cause: Heavy Rain
Property damage: 10.00K
Crop damage: 0.00K
Reported by: Law Enforcement

Numerous roads were closed and impassable due to flood waters especially in and around Navasota.

Thunderstorm Wind in COLORADO, TEXAS
From 25-MAY-15 20:20:00 to 25-MAY-15 20:20:00 (CST-6)
Location: BERNARDO
Magnitude: 60.00 EG
Property damage: 0.00K
Crop damage: 0.00K
Reported by: Law Enforcement

Thunderstorm wind damage was reported in Bernardo.

Flash Flood in FORT BEND, TEXAS
From 25-MAY-15 21:00:00 to 26-MAY-15 05:00:00 (CST-6)
Location: CLODINE
Flood cause: Heavy Rain
Property damage: 1.00M
Crop damage: 0.00K
Reported by: Broadcast Media

Flash flooding occurred across the central and eastern part of the county. There were vehicles flooded with numerous impassable roadways in and around the Sugar Land and Rosenberg areas. There was one drowning fatality.

Flash Flood in COLORADO, TEXAS
From 25-MAY-15 20:30:00 to 25-MAY-15 23:00:00 (CST-6)
Location: WEIMAR
Flood cause: Heavy Rain
Property damage: 0.00K
Crop damage: 0.00K
Reported by: Law Enforcement

Numerous roads were flooded throughout the county.

Funnel Cloud in COLORADO, TEXAS
From 25-MAY-15 18:13:00 to 25-MAY-15 18:13:00 (CST-6)
Location: WEIMAR
Property damage: 0.00K
Crop damage: 0.00K
Reported by: Law Enforcement

A funnel cloud was sighted north of Interstate 10 near Weimar.

Flash Flood in HARRIS, TEXAS
From 25-MAY-15 21:30:00 to 26-MAY-15 05:00:00 (CST-6)
Location: NASSAU BAY
Flood cause: Heavy Rain
Property damage: 25.00M
Crop damage: 0.00K
Reported by: Emergency Manager

Heavy rain produced flash flooding in and around the city of Houston that caused numerous creek and bayou overflows.  Multiple water rescues were conducted.  Numerous roads were impassable due to flooding that was as high as six feet deep.  Hundreds of vehicles were stranded in the flood water.  Flood waters inundated at least 2,585 homes and 73 commercial buildings. Many bayous, including Brays, Keegans, Buffalo (610 Loop to Downtown Houston), White Oak, Armand, and Halls were out of banks. Additional flooding occurred along Brickhouse Gully, South Mayde Creek, San Jacinto River, Clear Creek, Rummel Creek, Willow Water Hole, Cypress Creek, Little Cypress Creek, Willow Creek and Spring Creek.  There were six directly related drowning fatalities.

Flash Flood in BRAZOS, TEXAS
From 25-MAY-15 17:00:00 to 25-MAY-15 19:30:00 (CST-6)
Location: BRYAN
Flood cause: Heavy Rain
Property damage: 5.00K
Crop damage: 0.00K
Reported by: Law Enforcement

Numerous roads were closed and impassable in Bryan. High water rescues needed.

Flash Flood in WALKER, TEXAS
From 25-MAY-15 18:35:00 to 25-MAY-15 20:15:00 (CST-6)
Location: HUNTSVILLE ARPT
Flood cause: Heavy Rain
Property damage: 0.00K
Crop damage: 0.00K
Reported by: Law Enforcement

Numerous roads were closed and impassable north of Huntsville.

Hail in FORT BEND, TEXAS
From 26-MAY-15 02:45:00 to 26-MAY-15 02:45:00 (CST-6)
Location: FRESNO
Magnitude: 1.75 
Property damage: 0.00K
Crop damage: 0.00K
Reported by: Public

Golf ball sized hail was reported north of Fresno.

Thunderstorm Wind in WASHINGTON, TEXAS
From 25-MAY-15 18:26:00 to 25-MAY-15 18:26:00 (CST-6)
Location: KLUMP
Magnitude: 55.00 EG
Property damage: 0.00K
Crop damage: 0.00K
Reported by: Law Enforcement

Large trees were downed at the intersection of Dogwood Road and Adamek Road.

Thunderstorm Wind in WASHINGTON, TEXAS
From 25-MAY-15 18:29:00 to 25-MAY-15 18:29:00 (CST-6)
Location: MUELLERSVILLE
Magnitude: 60.00 EG
Property damage: 0.00K
Crop damage: 0.00K
Reported by: Law Enforcement

Thunderstorm winds downed trees along FM 332.

Thunderstorm Wind in HOUSTON, TEXAS
From 25-MAY-15 17:30:00 to 25-MAY-15 17:30:00 (CST-6)
Location: HOUSTON CITY
Magnitude: 55.00 EG
Property damage: 0.00K
Crop damage: 0.00K
Reported by: Law Enforcement

Thunderstorm winds downed trees.

Flash Flood in HOUSTON, TEXAS
From 25-MAY-15 17:55:00 to 25-MAY-15 19:15:00 (CST-6)
Location: CROCKETT
Flood cause: Heavy Rain
Property damage: 0.00K
Crop damage: 0.00K
Reported by: Law Enforcement

Numerous roads were closed in and around Crockett.

Thunderstorm Wind in AUSTIN, TEXAS
From 25-MAY-15 19:10:00 to 25-MAY-15 19:10:00 (CST-6)
Location: NEW ULM
Magnitude: 60.00 EG
Property damage: 0.00K
Crop damage: 0.00K
Reported by: Law Enforcement

Thunderstorm winds caused some damage along FM 1094.

Thunderstorm Wind in WASHINGTON, TEXAS
From 25-MAY-15 18:35:00 to 25-MAY-15 18:35:00 (CST-6)
Location: BRENHAM
Magnitude: 60.00 EG
Property damage: 0.00K
Crop damage: 0.00K
Reported by: Law Enforcement

Thunderstorm winds downed numerous trees in Brenham.

Thunderstorm Wind in WASHINGTON, TEXAS
From 25-MAY-15 18:45:00 to 25-MAY-15 18:45:00 (CST-6)
Location: CHAPPELL HILL
Magnitude: 60.00 EG
Property damage: 0.00K
Crop damage: 0.00K
Reported by: Law Enforcement

Thunderstorm winds downed trees along FM 1371.

Flash Flood in WASHINGTON, TEXAS
From 25-MAY-15 19:00:00 to 26-MAY-15 06:00:00 (CST-6)
Location: BERLIN
Flood cause: Heavy Rain
Property damage: 0.00K
Crop damage: 0.00K
Reported by: Law Enforcement

Numerous roads were closed in the Brenham area.

Flash Flood in GRIMES, TEXAS
From 25-MAY-15 19:00:00 to 25-MAY-15 23:30:00 (CST-6)
Location: ANDERSON
Flood cause: Heavy Rain
Property damage: 0.00K
Crop damage: 0.00K
Reported by: Law Enforcement

Numerous roads were closed in Anderson. Numerous roads were closed in Plantersville.

Funnel Cloud in LIBERTY, TEXAS
From 25-MAY-15 19:16:00 to 25-MAY-15 19:16:00 (CST-6)
Location: EXCELSIOR
Property damage: 0.00K
Crop damage: 0.00K
Reported by: Emergency Manager

A funnel cloud was sighted near the intersection of Highway 59 and Highway 105.

Hail in HARRIS, TEXAS
From 25-MAY-15 19:59:00 to 25-MAY-15 19:59:00 (CST-6)
Location: BELLAIRE
Magnitude: 0.75 
Property damage: 0.00K
Crop damage: 0.00K
Reported by: Trained Spotter

Dime sized hail was reported near the intersection of Beltway 8 and Meadowglen Lane.

Flash Flood in MADISON, TEXAS
From 25-MAY-15 18:30:00 to 25-MAY-15 21:00:00 (CST-6)
Location: LACEOLA
Flood cause: Heavy Rain
Property damage: 0.00K
Crop damage: 0.00K
Reported by: Law Enforcement

Numerous impassable roads were closed due to flood waters in Madisonville and Midway.

Thunderstorm Wind in HARRIS, TEXAS
From 25-MAY-15 20:23:00 to 25-MAY-15 20:23:00 (CST-6)
Location: ADDICKS
Magnitude: 60.00 EG
Property damage: 0.00K
Crop damage: 0.00K
Reported by: Fire Department/Rescue

Thunderstorm winds downed trees near the intersection of Eldridge Parkway and Briar Forest.

Flash Flood in WALLER, TEXAS
From 25-MAY-15 20:30:00 to 25-MAY-15 22:30:00 (CST-6)
Location: HEMPSTEAD ARPT
Flood cause: Heavy Rain
Property damage: 0.00K
Crop damage: 0.00K
Reported by: Law Enforcement

Numerous roads were closed across the county.

Thunderstorm Wind in AUSTIN, TEXAS
From 25-MAY-15 20:30:00 to 25-MAY-15 20:30:00 (CST-6)
Location: SEALY
Magnitude: 60.00 EG
Property damage: 0.00K
Crop damage: 0.00K
Reported by: NWS Employee

Thunderstorm winds downed large tree limbs onto a home. Several wood panel fences were also down.

Thunderstorm Wind in AUSTIN, TEXAS
From 25-MAY-15 20:34:00 to 25-MAY-15 20:34:00 (CST-6)
Location: SEALY
Magnitude: 56.00 EG
Property damage: 0.00K
Crop damage: 0.00K
Reported by: Trained Spotter

Wind gust was estimated just west of San Felipe.

Thunderstorm Wind in WALLER, TEXAS
From 25-MAY-15 20:40:00 to 25-MAY-15 20:40:00 (CST-6)
Location: KATY
Magnitude: 60.00 EG
Property damage: 0.00K
Crop damage: 0.00K
Reported by: Law Enforcement

Thunderstorm winds downed some trees.

Flash Flood in LIBERTY, TEXAS
From 25-MAY-15 20:40:00 to 26-MAY-15 04:30:00 (CST-6)
Location: CLEVELAND
Flood cause: Heavy Rain
Property damage: 0.00K
Crop damage: 0.00K
Reported by: Law Enforcement

There were numerous roads flooded in Cleveland.  Several roads were closed and impassable in Liberty.

Flash Flood in AUSTIN, TEXAS
From 26-MAY-15 04:40:00 to 26-MAY-15 06:00:00 (CST-6)
Location: KENNEY
Flood cause: Heavy Rain
Property damage: 0.00K
Crop damage: 0.00K
Reported by: Law Enforcement

Several roads were closed and impassable between Bellville and Chappell Hill.

Thunderstorm Wind in HOUSTON, TEXAS
From 25-MAY-15 17:35:00 to 25-MAY-15 17:35:00 (CST-6)
Location: WECHES
Magnitude: 60.00 EG
Property damage: 0.00K
Crop damage: 0.00K
Reported by: Broadcast Media

Thunderstorm winds downed trees in Weches.

Thunderstorm Wind in WASHINGTON, TEXAS
From 25-MAY-15 18:31:00 to 25-MAY-15 18:31:00 (CST-6)
Location: BERLIN
Magnitude: 60.00 EG
Property damage: 0.00K
Crop damage: 0.00K
Reported by: Law Enforcement

Trees were downed near the intersection of Old Mill Creek Road and South Berlin Road.

Flash Flood in SAN JACINTO, TEXAS
From 25-MAY-15 20:00:00 to 25-MAY-15 22:00:00 (CST-6)
Location: EVERGREEN
Flood cause: Heavy Rain
Property damage: 0.00K
Crop damage: 0.00K
Reported by: Law Enforcement

Roads were closed due to flooding throughout the Sam Houston National Forest and around the Lake Livingston Dam.

Thunderstorm Wind in WHARTON, TEXAS
From 26-MAY-15 01:32:00 to 26-MAY-15 01:32:00 (CST-6)
Location: HUNGERFORD
Magnitude: 60.00 EG
Property damage: 0.00K
Crop damage: 0.00K
Reported by: Law Enforcement

Thunderstorm wind damage was reported near County Road 216 and Machaville Road. There was some tree damage and home window damage.

Hail in HARRIS, TEXAS
From 26-MAY-15 03:17:00 to 26-MAY-15 03:17:00 (CST-6)
Location: ELLINGTON FIELD
Magnitude: 0.75 
Property damage: 0.00K
Crop damage: 0.00K
Reported by: Trained Spotter

Dime sized hail was reported near the intersection of Clear Lake City Blvd and El Camino Real.

Thunderstorm Wind in WALLER, TEXAS
From 25-MAY-15 19:40:00 to 25-MAY-15 19:40:00 (CST-6)
Location: WALLER
Magnitude: 60.00 EG
Property damage: 0.00K
Crop damage: 0.00K
Reported by: Law Enforcement

Thunderstorm winds downed numerous trees throughout the eastern part of the county.

Hail in BRAZORIA, TEXAS
From 26-MAY-15 02:58:00 to 26-MAY-15 02:58:00 (CST-6)
Location: MANVEL
Magnitude: 0.75 
Property damage: 0.00K
Crop damage: 0.00K
Reported by: Trained Spotter

Dime size hail was reported between Manvel and Pearland.

Thunderstorm Wind in COLORADO, TEXAS
From 25-MAY-15 18:20:00 to 25-MAY-15 18:20:00 (CST-6)
Location: FRELSBURG
Magnitude: 55.00 EG
Property damage: 0.00K
Crop damage: 0.00K
Reported by: Law Enforcement

Thunderstorm winds downed trees on Old New Ulm Road.