Outflow boundaries from an earlier supercell on October 18th in Willacy and Kenedy Counties triggered another supercell storm which cycled through eastern Hidalgo County between 6 and 7 pm CDT. Unrelated cells produced additional damage and heavy rainfall farther west, including in Donna, Edinburg, and McAllen.  The supercell storm dropped quarter to golfball size hail and lifted a metal roof from a cinderblock shed at one residence 3 miles north of Elsa. Preliminary wind speed estimate from this storm was 65 to 70 mph.

Hail in HIDALGO, TEXAS
From 18-OCT-12 17:45:00 to 18-OCT-12 17:50:00 (CST-6)
Location: MERCEDES OLD REB ARP
Magnitude: 1.00 
Property damage: 0.00K
Crop damage: 0.00K
Reported by: Public

Public reported quarter size hail at the intersection of Mile 12 and FM 491.

Hail in HIDALGO, TEXAS
From 18-OCT-12 17:30:00 to 18-OCT-12 17:40:00 (CST-6)
Location: ELSA
Magnitude: 1.75 
Property damage: 0.00K
Reported by: Public

Public reported quarter to golf ball size hail at Monte Cristo and Filegonia Road in Elsa. Hail fell at approximately 630 PM, according to the report and radar reconciliation, and appears to have continued at quarter to golf-ball sized as the updraft redeveloped over and just south of Edcouch between 630 and 640 PM CDT.

Hail in HIDALGO, TEXAS
From 18-OCT-12 17:10:00 to 18-OCT-12 17:25:00 (CST-6)
Location: MONTE ALTO
Magnitude: 1.75 
Property damage: 0.00K
Reported by: Public

A supercell thunderstorm dropped hail the size of golfballs across a several mile swath of rural eastern Hidalgo County. The initial reports from the  public indicated golf ball sized hail fell in Monte Alto at 615 pm CDT; radar reconcilation suggested the hail core drifted southward from Monte Alto for about 2.5 miles (north of Edcouch/Elsa) between 610 PM and 625 PM.

Heavy Rain in HIDALGO, TEXAS
From 18-OCT-12 17:45:00 to 18-OCT-12 18:25:00 (CST-6)
Location: EDINBURG
Property damage: 0.00K
Crop damage: 0.00K
Reported by: Public

Public reported water over the curbs in Edinburg, near the intersection of Trenton and 281, on either side of 7 PM CDT. Estimated two inches of rain fell in a short period of time in the area.

Thunderstorm Wind in HIDALGO, TEXAS
From 18-OCT-12 17:17:00 to 18-OCT-12 17:17:00 (CST-6)
Location: ELSA
Magnitude: 61.00 EG
Property damage: 7.50K
Reported by: Emergency Manager

Estimated thunderstorm wind gusts of 65 to 70 mph, lifted a metal roof from a cinderblock shed at the residence of the brother of the Hidalgo County Emergency Manager, 3 miles north of Elsa. Debris from roof and building also injured livestock.

Thunderstorm Wind in HIDALGO, TEXAS
From 18-OCT-12 18:15:00 to 18-OCT-12 18:15:00 (CST-6)
Location: MC ALLEN
Magnitude: 50.00 EG
Property damage: 5.00K
Crop damage: 0.00K
Reported by: Amateur Radio

An amateur radio operator in McAllen reported a carport had blown into adjacent building by thunderstorm winds. A nearby carport also damaged, all around the intersection of  at Houston Street and 6th Avenue.

Thunderstorm Wind in HIDALGO, TEXAS
From 18-OCT-12 17:55:00 to 18-OCT-12 17:55:00 (CST-6)
Location: DONNA
Magnitude: 48.00 EG
Property damage: 1.00K
Crop damage: 0.00K
Reported by: Public

Internet report of a large-diameter tree blown down by thunderstorm winds near the intersection of North Victoria and Mile 10 Road, just north of Donna.  Radar reconciliation suggest the winds fell just below severe limits.