Update: Monster Storm Across US Kills at Least 40

At least 40 people are dead after tornadoes, high winds and wildfires hit more than a half-dozen states since Thursday.

Although the Sunday outlook was less dire, more severe thunderstorms with potential tornadoes were expected from Pennsylvania to Florida.

Fatalities occurred in Georgia, Mississippi, Arkansas and Alabama from tornadoes that raced at highway speeds on Friday through Saturday night and into Sunday morning.

States of emergency were in effect due to storms in Georgia, Mississippi, Alabama and Arkansas, where President Trump said in a Sunday statement the National Guard had been deployed.

The storms had prompted the National Weather Service to issue a rare "high risk" threat designation for Mississippi and Alabama on Saturday, as multiple rounds of intense thunderstorms swept across these states.

Hard-hit communities include Taylorsville, Miss., and Calera, Ala., among many others, after tornadoes struck at night.

The storms even targeted at least one NWS office, with forecasters at NWS Birmingham forced to take shelter as a tornado passed close to their building Saturday evening.

The extreme storms have resulted in at least 12 deaths reported in Missouri, six in Mississippi and three each in Alabama and Arkansas.

Dust storms that caused low visibility on Friday resulted in road crashes that killed at least eight people in Kansas and four others in Texas.

Oklahoma officials confirmed at least four deaths due to "dangerous" wildfires with "straight-line-winds" that saw Gov. Kevin Stitt declare an emergency in 12 counties on Saturday.

Severe thunderstorms were bringing scattered damaging wind swaths and some tornadoes into Sunday evening across parts of the Ohio Valley into the Mid-Atlantic and Southeast.

Tornado warnings were in effect for parts of Florida and North Carolina, and watches for other portions N.C. and southern Virginia as of Sunday night.

About 38 million people live in areas designated at "slight" to "enhanced" risk of severe thunderstorms on Sunday.

Dozens of tornadoes, many of them confirmed by the NWS, have been reported from the Midwest to the Southeast since Friday.

These numbers are likely to increase on Sunday, despite the lower overall risk level.