Corpus Christi flooded with over 10 inches of rain

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What happened and where?

On the morning of Sunday, April 25th, heavy rain inundated the southern Coastal Bend of Texas. Showers and thunderstorms began to form over Kleberg and Kenedy counties around 2 a.m. These storms intensified and moved north into western Nueces and San Patricio counties through 3 a.m. From 3 a.m. to 5 a.m. additional thunderstorms developed across Kleberg county and southern Nueces county and moved northeast across the Corpus Christi metro area. By 5 a.m the heaviest rainfall stretched from Taft to downtown Corpus Christi to Chapman Ranch. National Weather Service (NWS) Doppler radar estimated rainfall rates close to 2 inches per hour across this area. From 5 a.m. to 9 a.m. thunderstorms continued to reform over the south side of Corpus Christi and move northeast across the city, resulting in a training effect of storms. The heaviest showers and thunderstorms eventually tapered off and moved east between 10 a.m. and noon. NWS radar estimated widespread 5 to 8 inches of rainfall across most of Nueces and San Patricio counties east of U.S. 77. A bull�s eye of 7 to 10 inches of rainfall was estimated across much of the south side of Corpus Christi.

The heavy rainfall produced extensive flooding of primary and secondary roads in Nueces and San Patricio counties. The Corpus Christi Police Department reported over 100 vehicles stalled in Corpus Christi, with some drivers needing to be rescued. The water reached into several homes in Tuloso-Midway and Taft as well as isolated spots across the south side of Corpus Christi. Numerous city streets and intersections were not passable due to the flooding. Flooding along Interstate 37 was also reported near Calallen, Five Points and Annaville, triggering closures.

In addition to drivers and residents being impacted, the extensive heavy rainfall compounded ongoing river flooding problems throughout the month of April, especially along the Nueces River. Flash flood warnings were first issued by the NWS office in Corpus Christi beginning at 432 a.m. for Nueces and San Patricio counties. These warnings extended through the morning and into the afternoon before eventually being lifted as flooding subsided.

Area rainfall totals� Official ASOS and NWS COOP observations  

   Location Amount (inches)

Records�
New daily rainfall record for April 25th set at Corpus Christi International Airport: 6.18 inches (previously 3.76 inches in 1996).
New monthly rainfall record for April established: 9.21 inches (previously 8.04 inches during April 1956).

Why did it happen?

A cold front became nearly stationary from near Victoria to Alice during the early morning hours of the 25th. A surface low formed across Deep South Texas and slowly tracked northeast. Analysis revealed strong easterly gulf inflow on the north side of the low, resulting in strong moisture convergence along the stalled front across the Southern Coastal Bend. This led to the development and redevelopment of strong showers and thunderstorms over Nueces and San Patricio counties, producing a scenario in which thunderstorms upstream moved along the same path as earlier storms much like boxcars on a train.