Desperate locals and tourists are in survival mode in the resort area of Los Cabos, with electrical and water service still out three days after Hurricane Odile made landfall as a monster Category 3 storm.
Looters stripped supermarkets of their food and other products, with some people fighting over goods.
At least one supermarket decided to give away its merchandise. People pushed shopping carts full of goods that at times clogged the highway.
Mexico's government continued to fly stranded tourists out of the area as the remnants of Odile drenched the northern state of Sonora and headed on a path forecast to take the rain into Arizona overnight.
The US National Hurricane Center said parts of Arizona and New Mexico could get 15 to 23 centimetres of rain and warned of possible flash flooding.
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The Tucson area was forecast to bear the brunt of the storm on Wednesday, but Phoenix could also be lashed with rain and heavy winds.
To the south, a new tropical storm was nearing hurricane strength off Mexico's Pacific coast and headed in the general direction of Los Cabos, although early predictions were for the centre to remain offshore.
President Enrique Pena Nieto's office said the federal government was working closely with state authorities on relief efforts in the areas battered by Odile, including restoring water and electricity.
It said more than 239,000 people had their power knocked out by the storm, but predicted 95 per cent of electrical service would be restored within four days.
