Millions of Americans remain under extreme heat warnings from the Central Seaboard to the Central Plains, where the AccuWeather RealFeel dangerous Temperatures will once again mark the turn of the century.
Power companies have braced for a surge in energy consumption, which will bring another day of temperatures soaring into the 90s and lower 100s of the Southern Plains to the Ohio Valley and Northeast on Sunday.
Close to 60 million Americans live along the Interstate-95 corridor from New England to the Mid-Atlantic, where daily record-high temperatures are once again in jeopardy.
“With temperatures nearing the day that are nearing the highs of the day, the heat wave of the hottest day of the year could be all along the Interstate-95 corridor from Boston to New York City, Philadelphia and Washington, DC.
The Summer Scorcher will bring highs in the 90s to near 100 F with AccuWeather RealFeel® Temperatures forecast near Spike 110 for some urban areas in the late morning and afternoon.
100 F are expected in Washington, D.C., Baltimore, Philadelphia, New York City and Boston once again on Sunday.
At this level, the hot July months of 2012, 2011, 1991, 1980 and 1930 will be rivaled. Forecast temperatures are 10-15 degrees above Fahrenheit average, even for the middle of summer.
For a time, it may feel just as hot in Washington, D.C., as Death Valley, California. While the actual temperature may be higher in the Death Valley, the Chesapeake Bay will be significantly higher than the nation’s capital and humidity levels.
For example, dew point temperatures will range from the teens to the lower 30s in the deserts, but the beaches in the lower 70s to the lower 80s at Chesapeake Bay. The dew point is the temperature at which the air is cooled when the water vapor is saturated. When this happens, the relative humidity reaches 100 percent.
However, near-100-degree temperatures are associated with higher humidity rates than those in the Southwest.
Both areas are dangerous in the heat, but in combination with the vastly-paved areas and heavy populations, the health risks are higher than in the more humid regions.
High nighttime temperatures allow the heat to build up to an even faster pace the next day and overnight humidity levels can be higher than they are in the afternoon.
In some of the major cities, temperatures may not drop below 80 at night.
Reference-
Accu weather