Summary of July 2010 Weather across the Rio Grande Valley

Rainfall Across Deep South Texas, July, 2010 (click to enlarge)

Preliminary measured and estimated rainfall across Deep South Texas, July, 2010.

From Famine to Feast?
July 2010’s Normalcy in Stark Contrast to July 2009 Heat/Drought

Overview
What a difference a year makes. Or maybe, two years? Since 2008, July has been the most changeable of months in Deep South Texas. Hearkening back, 2008 featured drought breaking rains to begin the month, followed by widespread flooding in the Rio Grande Valley from Hurricane Dolly. 2009 turned 2008 on its head, with record breaking temperatures and severe to exceptional drought fed by the combination of a strong upper level ridge extending from the western Gulf into the relatively dry Southwest U.S. and northern Mexico. The latest July, 2010, was relatively uneventful. That said, rainfall was significantly above the long term average in portions of the Rio Grande Valley, courtesy of Tropical Depression Number 2 and occasional passages of weak energy impulses. Temperatures were held in check, generally within a degree or so of the long term average, by the upper level pattern featuring a central Atlantic to Southern Plains ridge which favors broader east and southeast flow of tropical moisture and energy impulses. Relatively high soil moisture levels, aided by an occasionally wet April and May followed by widespread heavy rains from Hurricane Alex to close June, may have contributed to the more typical July values. The biggest swing was noted at McAllen/Miller Airport, where average highs dropped more than 11°F between 2009 (104°F) and 2010 (93°F)!

A brief climate review for July 2010 follows. Additional rainfall information, links, and other data will be added before the end of the week


PUBLIC INFORMATION STATEMENT
NATIONAL WEATHER SERVICE BROWNSVILLE TX
904 AM CDT SUN AUG 1 2010
 
...JULY 2010 CLIMATE ROUNDUP FOR DEEP SOUTH TEXAS...
 
RECORD DATES FOR EACH LOCATION ARE AS FOLLOWS:
 
BROWNSVILLE RECORDS BEGAN 1878...
HARLINGEN RECORDS BEGAN 1911...
MCALLEN RECORDS BEGAN 1941...
 
.BROWNSVILLE...
 
THE AVERAGE TEMPERATURE IN BROWNSVILLE FOR JULY WAS 84.94
DEGREES...1.0 DEGREES ABOVE NORMAL. THIS IS TIED FOR THE 30TH
WARMEST JULY ON RECORD FOR BROWNSVILLE. ONE RECORD HIGH MINIMUM
TEMPERATURE WAS TIED ON THE 3RD. ONE RECORD LOW MAXIMUM TEMPERATURE
WAS SET ON THE 28TH.
 
BROWNSVILLE AIRPORT RECEIVED 5.14 INCHES OF RAIN IN JULY...3.37
INCHES ABOVE NORMAL. THIS IS THE 10TH WETTEST JULY IN BROWNSVILLE
HISTORY. ONE RECORD DAILY RAINFALL WAS SET ON THE 8TH.
 
.HARLINGEN...
 
THE AVERAGE TEMPERATURE IN HARLINGEN FOR JULY WAS 83.79
DEGREES...0.6 DEGREES BELOW NORMAL. THIS IS THE 31ST COOLEST JULY ON
RECORD. TWO RECORD HIGH MINIMUM TEMPERATURES WERE SET ON THE 3RD AND
14TH. ONE RECORD LOW MAXIMUM TEMPERATURE WAS SET ON THE 28TH.
 
HARLINGEN AIRPORT RECEIVED 2.05 INCHES OF RAIN IN JULY...0.34 INCHES
ABOVE NORMAL. THIS IS THE 35TH WETTEST JULY IN HARLINGEN.
 
.MCALLEN...
 
THE AVERAGE TEMPERATURE IN MCALLEN FOR JULY WAS 85.31 DEGREES...0.6
DEGREES BELOW NORMAL. THIS IS THE 34TH WARMEST AND 34TH COOLEST JULY
ON RECORD FOR MCALLEN. THIS IS ALSO 7.5 DEGREES LOWER THAN THE
RECORD SETTING AVERAGE TEMPERATURE RECORDED IN 2009. FOUR RECORD
HIGH MINIMUM TEMPERATURES WERE SET ON THE 2ND...3RD...4TH AND 14TH.
ONE RECORD LOW MAXIMUM TEMPERATURES WAS SET ON THE 28TH.
 
MCALLEN AIRPORT RECEIVED 3.61 INCHES OF RAIN IN JULY...1.96 INCHES
ABOVE NORMAL. THIS IS THE 8TH WETTEST JULY ON RECORD. ONE DAILY
RECORD RAINFALL WAS RECORDED ON THE 28TH. RAINFALL WAS RECORDED IN
MCALLEN ON 13 SEPARATE DAYS IN JULY. THIS SETS THE MONTHLY
RECORD...BREAKING THE PREVIOUS RECORD OF 11 SET IN 1976...1999 AND
2007. FIVE OF THE 10 WETTEST MONTHS OF JULY IN MCALLEN HAVE
OCCURRED SINCE 2005. MCALLEN HAS ALSO REACHED ITS YEARLY AVERAGE FOR
PRECIPITATION.