“Your principal right is to life, don’t risk it. The heat in the desert can be fatal. If you see a corpse, call this number.”

I see the stark warning in Spanish on a sign as we pull in to the remote clutch of adobe and cinderblock homes that make up El Sasabe on the Arizona border. But it seems that we are more in danger of drowning than the heat we prepared for.

Thunder storms are rumbling in over the desert on both sides of the border. Migrants warned us yesterday of the summer monsoon rains that fill the washes and creeks of the Sonora Desert with bucking torrents of water in just a matter of minutes. I realize the one thing I don`t have is a rain coat.

I buy a plastic poncho for $1.50 at the aptly named store Super el Coyote the slang term for a people smugglers and we start getting our packs ready for a walk up to the border post at the start of our 45-mile trek over the desert.

Then the heavens open. Torrents of rain thunder down from the sky and lightening sparks through the heavy grey clouds. Gone are the huge open skies of blue, the heat and the dust. The dirt streets of El Sasabe are streams and I realize my plastic poncho is woefully in adequedate. I am utterly unprepared.

I pack my backpack and step out into the rain, my blue sun hat keeping off the water from my face. My shirt is already beginning to soak up the water. My shoes are wet.

As the darkness gathers, I walk with Tomas toward the U.S. border crossing at Sasabe.

We agreed that Robin should take the hire car and will follow us by road to give us support if we should need it. Our TV cameraman Manuel takes my truck. I have a satellite phone and he has his cellular phone. We all cross through the Sasabe port of entry into the United States.

The rain is belting down. “I hope you can swim,” laughs a U.S. Customs and Border Protection officer as we go off down the hill.