Outflows from thunderstorms, an unstable air mass, and an upper level disturbance moving across Deep South Texas set the stage for more showers and strong to severe thunderstorms moving across portions of the CWA the afternoon of May 27th and into the early morning hours of May 28th. Frequent lightning was common with a large cell in southern Cameron County; the same cell produced large hail, heavy rains, and a prolonged downburst that produced one wind damage event.
Another round of storms developed around midnight east of the Sierra Madre and west of Laredo, forming a large complex of thunderstorms which progressed through Deep South Texas after midnight. One set of storms containing a continuous hail core and possible microbursts raced through Zapata, Jim Hogg, Brooks, and Kenedy, Counties while other thunderstorms moved through Starr County and eastward through the Lower Rio Grande Valley.  All storms contained frequent cloud to ground lightning and locally torrential rains.

Heavy Rain in JIM HOGG, TEXAS
From 28-MAY-09 00:15:00 to 28-MAY-09 01:15:00 (CST-6)
Location: RANDADO
Property damage: 0.00K
Crop damage: 0.00K
Reported by: Law Enforcement

The Jim Hogg Sheriff's Department reported water along and over State Highway 16 near the city of Randado during and a little after a thunderstorm moved through the area with locally heavy rainfall, estimated by radar to be more than 2 inches. The water depth on Highway 16 was estimated to be in inches, and the road was still passable.

Lightning in HIDALGO, TEXAS
From 28-MAY-09 03:30:00 to 28-MAY-09 03:30:00 (CST-6)
Location: EDINBURG MUNI ARPT
Property damage: 1.00M
Crop damage: 0.00K
Reported by: Newspaper

Frequent cloud to ground lightning strikes, associated with continuing strong storms which had earlier produced locally heavy rains and large hail across portions of Jim Hogg, Starr, and Zapata County, moved across the McAllen/Edinburg area during the pre-dawn hours.  One of these strikes started a roof fire by igniting shingles at an estate home.  Within an hour, the blaze had engulfed the entire roof; residents were able to escape unharmed.  Video showed the house, as well as a vehicle, to be a total loss, with replacement estimated to be near $1 million.

Hail in CAMERON, TEXAS
From 27-MAY-09 16:22:00 to 27-MAY-09 16:30:00 (CST-6)
Location: PORT BROWNSVILLE
Magnitude: 1.75 
Reported by: Unknown

The manager of the Port of Brownsville reported golf ball size hail on the grounds as a severe thunderstorm moved slowly through.

Hail in JIM HOGG, TEXAS
From 28-MAY-09 00:15:00 to 28-MAY-09 00:20:00 (CST-6)
Location: HEBBRONVILLE
Magnitude: 1.75 
Property damage: 0.00K
Crop damage: 0.00K
Reported by: Law Enforcement

The Jim Hogg Sheriff���s Department reported golf ball size hail fell on Highway 16 approximately 10 miles south of the city of Hebbronville as a severe thunderstorm  moved through the area.

Thunderstorm Wind in CAMERON, TEXAS
From 27-MAY-09 16:25:00 to 27-MAY-09 16:30:00 (CST-6)
Location: PORT BROWNSVILLE
Magnitude: 52.00 EG
Property damage: 2.00K
Crop damage: 0.00K
Reported by: Public

The business manager of a ship breaking and metal processing firm at the Port of Brownsville reported a bolted down radio tower was blown down by microburst winds associated with a severe thunderstorm, which produced golf ball sized hail nearby.

Hail in CAMERON, TEXAS
From 27-MAY-09 15:35:00 to 27-MAY-09 15:40:00 (CST-6)
Location: LAURELES
Magnitude: 1.75 
Property damage: 0.00K
Crop damage: 0.00K
Reported by: NWS Employee

Family of a National Weather Service Employee reported hail up to golf ball size
during an intense thunderstorm just northwest of the center of Los Fresnos.