A dissipating cold front combined with an upper level disturbance and moist flow from the Gulf of Mexico, acted on increasingly unstable air just above the surface to produced several periods of strong thunderstorms from early morning through mid evening of November 13th.  Some of the storms became severe, dropping large hail during the mid morning and evening hours; heavy rainfall adding up to more than 3 inches in portions of Cameron County, with pockets of heavy rain elsewhere in the Lower Rio Grande Valley, produced nuisance minor flooding.

Hail in HIDALGO, TEXAS
From 13-NOV-08 08:05:00 to 13-NOV-08 08:25:00 (CST-6)
Location: DONNA
Magnitude: 0.88 
Property damage: 1.00K
Crop damage: 0.00K
Reported by: Broadcast Media

A severe thunderstorm with a pronounced hail core rolled through the Donna-Alamo area during the mid morning, dropping large hail in several areas. Nickel size hail fell along the federal highway 83 expressway in Donna, shattering at least one automobile windshield.  Penny size hail fell a bit later in and near Alamo.  In addition to the hail, 2.2 inches of rain fell near the Alamo Country Club in a short period of time, probably less than an hour.
The parent left-moving thunderstorm began across the Rio Grande in northern Mexico a little before 7 AM CST, and moved into extreme southern Hidalgo County near the Santa Ana National Wildlife Refuge around 730 AM. Large hail may well have occurred along this portion of the path, as well as northwest of Donna toward Edinburg, between 830 and 9 AM.

Heavy Rain in CAMERON, TEXAS
From 13-NOV-08 09:00:00 to 13-NOV-08 10:45:00 (CST-6)
Location: (BRO)BROWNSVILLE ARP
Property damage: 0.00K
Crop damage: 0.00K
Reported by: ASOS

Locally heavy rains accompanied several thunderstorms that affected the Brownsville-Port Isabel and Laguna Vista area during much of the day on the 13th.  The heaviest rains, dropping more than in inch in an hour, occurred generally between 9 and 1045 AM drifting northeast from the southeast portion of Brownsville toward Port Isabel and Laguna Vista.
Typical poor drainage flooding was likely observed on portions of Boca Chica Blvd. mainly east of the highway 77 expressway in Brownsville.
Calendar day rain totals at Brownsville/International Airport and Cameron County Airport (Bayview) were 2.76 and 3.05 inches, respectively.

Hail in ZAPATA, TEXAS
From 13-NOV-08 19:00:00 to 13-NOV-08 19:15:00 (CST-6)
Location: ZAPATA ARPT
Magnitude: 0.75 
Property damage: 0.00K
Crop damage: 0.00K
Reported by: Law Enforcement

The sheriff's Department reported dime to penny sized hail occurring at the sheriff's office in Zapata during a severe thunderstorm which was moving over their office.

Heavy Rain in CAMERON, TEXAS
From 13-NOV-08 12:15:00 to 13-NOV-08 13:15:00 (CST-6)
Location: STUART PLACE
Property damage: 0.00K
Crop damage: 0.00K
Reported by: Newspaper

Another in a round of locally heavy thunderstorms moved across Harlingen during the lunch hour, creating several instances of nuisance minor flooding. Radar estimated of up to 2 inches of rain caused high standing water at the intersection of North A Street and New Combes Highway, with other ponding along 77 Sunshine Strip.