Josh Morgerman, a Californian storm chaser, said his Cabo hotel "lobby exploded in heap of rubble." Writing on Twitter, Morgerman said he "escaped by crawling, scampering, running."
Chelsea Ballenberger, a nurse from Alabama holidaying in the nearby city of La Paz, said she was forced to take refuge in the shower when her room flooded. "As soon as we moved to the shower the windows shattered," she wrote on Facebook.
"We can hear the wind howling everywhere… Definitely the scariest thing I have ever been through." Jason T. Vogt, a Canadian expat, simply described the scene as "total devastation" in a Facebook post.
Weather Channel digital meterologist Nick Wiltgen said he was monitoring "mind-boggling" reports of 11 inches of rain in just one hour — almost the region's yearly average of 13 inches. While this measurement could be due to storm-damaged equipment, he said reports of seven inches were believable.
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"If past reports are anything to go by the most serious damage will be revealed when it gets light." The storm was bearing down on the 200,000 city of La Paz at 5.30 a.m. ET, but is expected to weaken as it heads up the peninsula through Tuesday. "Odile will induce a moisture surge into the Southwestern U.S. as soon as Tuesday, which could result in locally heavy rain and flash flooding," The Weather Channel reported.
—By Alexander Smith, NBC News. The Associated Press contributed to this report.