FEMA built 80 high tech emergency broadcast centers

"That served as kind of a staple in the community and a source of information for citizens when a number of the other broadcast facilities were off the air," says Antwane Johnson, who heads the emergency public alerts and warnings program for FEMA.
After Katrina, Johnson says FEMA realized the main reason for these doomsday bunkers was probably not an enemy missile anymore – it was Mother Nature. Millions of federal dollars have since built a network of nearly 80 high-tech emergency shelters to withstand hurricanes, tornadoes, solar flares - even an electromagnetic pulse that could cripple the nation's power grid.

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WBT Cold War Relic Gains New Relevance

I wrote about an "accidental" electromagnetic pulse in:

• EMP
• which in the fictional account was caused by a terrorist getting launch codes for a Russian 100 megaton hydrogen bomb set to blow up 100 miles above the U.S. Such a blast would knock out all power in the lower 48 states and nothing electrical that had been built would work again. So, new electrical equipment would have to be shipped in from other countries unaffected by the blast. "EMP" is a fictional account of surviving such a blast here in California in the U.S. Such a blast would likely kill around 70 million people because anyone within 12 feet of anything metal large enough would die from the electromagnetic pulse. The previous is a scientific theoretical fact researched by me over the years.

When I was 14 I read "Alas Babylon" which scared the hell out of me then in 1962.