Winds Buffet Valley for Semanta Santa
Wildfire Issues , Dangerous Surf Into March 18th March 17th 2008 water vapor, 3 PM CDT, showing strong upper level storm system in southwestern U.S.(click to enlarge)

UPDATE, 5 PM March 17th: As forecast, very strong winds rolled across the populated lower Rio Grande Valley during the late morning and afternoon on March 17th (St. Patrick's Day), with sustained winds ranging from 25 to near 40 mph at times, and continuous gusts from McAllen and Edinburg through Harlingen, Brownsville, and Port Isabel ranging from 45 to over 50 mph. The deepening system will maintain strong and gusty winds in excess of 30 mph with gusts to 40 mph or higher through much of the night, with similar south winds Tuesday morning shifting to the west by early afternoon at similar speeds as the trough sweeps across Texas. Even gustier winds are possible from Hidalgo and Brooks County westward to Zapata and Hebbronville by Tuesday afternoon, as west to northwest winds up to 40 mph with gusts to 50 mph are possible after the trough swings through. The table below shows peak wind gusts so far on March 17th:

Location
Peak Wind
Time (LT)
Harlingen/Valley Arpt
54 mph
1227 PM
Brownsville/Intl Arpt
48 mph
1044 AM
McAllen/Miller Arpt
48 mph
149 PM
Weslaco/Arpt
48 mph
200 PM
Port Isabel/Bayview Arpt
47 mph
120 PM
Edinburg
44 mph
305 PM
Falfurrias/Brooks Co. arpt
43 mph
245 PM
Hebbronville/Jim Hogg arpt
32 mph
1105 AM

Beach and Boating Danger
High surf, with an increasingly extreme danger for rip currents, poses life threatening risks for those who attempt to swim at area beaches. Even the most seasoned surfer will struggle with rough and confused surf conditions this evening through Tuesday. Seas in the nearshore Gulf of Mexico will continue to build, perhaps reaching 16 feet near the 60 nm marker east of Padre Island. Recreational boaters should remain in port through Tuesday. Wind speeds on Monday may reach 35 to 40 mph with gusts above 45 mph, and surf will become rough and confused, along with a high to extreme risk for Being St. Patrick's Day, visitors to South Padre Island are urged to be very cautious near the water. Late on the afternoon of March 17th, reports from South Padre Island indicated that numerous vehicles had been stranded on portions of the beach due to increasing surf and swell.

Explosive Wild Fire Growth Potential continuing through Tuesday
The winds on March 16th and 17th have already caused a number of minor wild fire spread issues, but conditions on the 18th may be even harsher, especially across the western portion of the lower Rio Grande Valley, where rain has been scarce or non existent since the beginning of 2008. Very dry conditions on March 14th and 15th, where daytime humidity fell below 5 percent in a few spots, have set the stage for fuels to burn. On Tuesday, the combination of gusty afternoon west winds in excess of 40 mph along with falling humidity into the teens and 20s will further exacerbate an already dangerous situation. Reinforcing items that can create sparks if blown down will remain imperative through March 18th. Some of the nation's worst large wild fires in recent years were caused by sparking power lines that were blown down by strong winds, including the Big Turnaround Complex in south Georgia and north Florida in 2007, and the Amarillo Complex which began on March 12, 2006. A near 100,000 acre fire was burning in south central Texas, near Cotulla, on March 15th.

Squall Line Tuesday?
The vigorous upper level system will roll into central Texas during the day Tuesday. Ahead of it, the atmosphere will quickly become unstable, and moisture will pool just ahead of the front from East and Southeast Texas southward into portions of Deep South Texas. One possible mitigating factor is the fairly strong low level inversion, which may act as a "cap" and suppress lift, especially since the event is expected to arrive during the morning into early afternoon. However, the strength of the upper system may be sufficient to lift the cap and allow for rapid development of strong to severe storms, with the potential for damaging straight line winds and perhaps an isolated tornado.

For more information, continue to surf to our web site. Stay tuned for a variety of watches, warnings, and advisories, as well as other updates for your area by navigating through the "point and click" forecast map on the front of our site, as well as short term graphicasts.

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