Many of the Midwest and Northeastern cities – from Chicago to Washington, DC and Philadelphia – began a heatwave on Friday. New York City, which missed a 90-degree reading by just one degree, is likely to reach the number Saturday to start its own trend.
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Temperatures will rise steeply in the 90s, the plains, the Midwest and the Northeast today again.
Friday's heat index was 110 degrees and higher in parts of Illinois and Wisconsin. Pontiac, Ill., Hit a heat index of 1
15 degrees. Chicago's Midway International Airport achieved a heat index of 110 degrees.
ABC News Dangerous heat has set off alarm on Saturday in the Midwest and Northeast.
The heat will expand northeast on Saturday with temperatures in the '90s and heat index levels in the early' 90s. The heat index in parts of the Midwest on Saturday could reach over 110 degrees, also in Greater Chicago.
ABC News The heat index readings will be in the 100s from Green Bay, Wisconsin, south to Houston.  Excessive heat warnings and alarms have been issued for many capital regions, including Kansas City, Missouri; Chicago; Detroit; Philadelphia; New York; Hartford, Connecticut; and Albany, New York. From Oklahoma to Vermont, heat recommendations were issued for large parts of the region.
The heat wave will hardly bring any relief even at night. The actual temperature at 21 o'clock. Friday night in Chicago was 90 degrees, with a three digit heat index. Low temperatures in some of the major metropolitan areas will have a hard time falling below 80 degrees during this heat period.
ABC News The hottest day of the heatwave will be in the northeast on Sunday.
The actual Sunday temperature will approach 100 degrees in New York City, Washington, DC, Philadelphia and Hartford, Connecticut. Heat index values will rise to the 100s, with localized 105 degree heat index values in urban areas of the northeast.
ABC News Sunday's temperatures will be at or near 100 degrees in many large cities in the northeast.
The heatwave is expected to last at least until July 4th. If the heat continues beyond vacation, this heat wave could reach some of the remarkably long heat waves recorded in places like New York City and Albany, New York.
Thunderstorms hit northern plains
Another round of thunderstorms will rise today in parts of the Midwest with devastating winds, big hail and short tornados from Kansas on Michigan's Upper Peninsula. There is an increased risk of severe weather in parts of eastern Nebraska and Iowa where locally destructive winds and heavy hail can occur. The tornado threat is greatest in this region.
ABC News There is a possibility for strong winds and big hail from the plains northeast through Wisconsin on Saturday. 19659009] Cities that could experience severe weather today are Des Moines, Iowa; Omaha, Nebraska; Kansas City, Missouri; and Minneapolis.
In addition, the storms will move slowly as the main ridge of high pressure brings the heat wave east. Slow thunderstorms cause possible flooding. Locally, 2 to 3 inches of rain is expected in parts of eastern Nebraska and Iowa, with 3 to 4 inches or higher locally possible.
Fire danger continues
There are currently 56 large forest fires in the western United States from New Mexico to Alaska.
The spring fire in Costilla County, Colorado, has burned 28,648 acres and is contained 0 percent. Due to the fire, forced evictions are required in this area.
The Waverly Fire caused evacuation on Friday in Milton, California. The fire burned 10,000 hectares and is only 10 percent contained.
ABC News There is a fire hazard in Utah and Northern California on Saturday.
It will be another warm day of the West. Temperatures in today's parts of California's interior will be nearly 100 degrees.
Artillery winds, low relative humidity and high heat will bring the next round of high fires in parts of Northern California and Utah.