热度是第一名与天气有关杀手——它正朝着美国人口最稠密的地区长时间移动。
一场以三位数天气笼罩中西部和东北部的热浪预测预计将在夏季的第一天到来。
但是在炙热之前，美国中部和东海岸的大部分地区将不得不忍受至少几天的恶劣天气。
在接下来的两天里，从中西部到东海岸，超过1.2亿人受到严重风暴的威胁。
周三，从密歇根州到密苏里州，包括印第安纳波利斯和路易斯维尔市，恶劣天气的风险为五分之三，可能会产生破坏性的风、龙卷风、大冰雹和可能的山洪。与此同时，芝加哥、底特律、辛辛那提、纳什维尔和德克萨肯纳等城市周三面临的恶劣天气风险为5级中的2级。
预计风暴将在周三午餐时间到达芝加哥，并在下午晚些时候进入印第安纳波利斯、底特律和辛辛那提。纳什维尔和德克萨肯纳预计将在周三晚上和夜间遭遇恶劣天气。
周四，恶劣天气预计将转移到东海岸，从北卡罗来纳州到佛蒙特州，包括华盛顿特区和纽约市。
在西部，从凤凰城到拉斯维加斯，周四和周五都有极端高温警告，气温可能飙升至115度。
西部的炎热天气预计也会提高从内华达州到科罗拉多州的火灾风险。美国国家气象局(National Weather Service)周三下午和晚上向科罗拉多州西北部和犹他州东北部发出了红旗警告，在这些地方，35英里/小时的阵风和一位数的湿度可能会引发火灾并迅速蔓延。
到本周末，西部部分地区的日最高气温记录可能会下降，像丹佛这样的地方可能会超过100度。
准备迎接这个季节的第一波热浪
从周日开始，炎热的天气将侵袭中西部和东南部的部分地区。天气预报称，芝加哥、路易斯维尔和纳什维尔的气温将超过100度。
到周一，破纪录的日高温预计将在大西洋中部和东北部蔓延，最高气温将从90度左右到100度左右。
高湿度将使数千万人的生活更加闷热。高温指数是衡量气温感觉的指标，预计周一纽约市、波士顿和华盛顿特区的高温指数将升至100多度，并持续到下周。
在热浪期间，夜间温度预计只会下降到70度，这意味着如果没有足够的空调，这种热浪对许多美国人来说将是极其危险的。
东北部危险的高温预计要到下周晚些时候才会消退，届时云和雨将进入该地区。
Life-threatening heat wave in the Midwest and Northeast to kick off official start of summer
Heat is the No. 1weather-relatedkiller -- and it’s heading to the most densely populated part of America for a prolonged period.
A heat wave forecast to envelop the Midwest and the Northeast with triple-digit weather is expected to arrive on the heels of the first official day of summer.
But before the sizzle, the country's midsection and much of the East Coast will have to endure at least a couple of days of severe weather.
Over the next two days, more than 120 million people are under the threat for severe storms from the Midwest to the East Coast.
The risk for severe weather -- which could produce damaging wind, tornadoes, large hail and possible flash flooding -- is at a level 3 out of 5 on Wednesday from Michigan to Missouri, including the cities of Indianapolis and Louisville. Meanwhile, the risk of severe weather for the cities of Chicago, Detroit, Cincinnati, Nashville and Texarkana is at a level 2 out of 5 on Wednesday.
Storms are expected to reach Chicago around the lunch hour on Wednesday and move into Indianapolis, Detroit and Cincinnati later in the afternoon. Nashville and Texarkana are expected to see severe weather Wednesday evening and and overnight.
On Thursday, severe weather is expected to move to the East Coast from North Carolina to Vermont and include Washington, D.C., and New York City.
Out West, extreme heat warnings are in place for Thursday and Friday from Phoenix to Las Vegas, where temperatures could soar to 115 over the region.
The hot weather in the West is also expected to elevate the risk of fire danger from Nevada to Colorado. The National Weather Service has issued red flag warnings for Wednesday afternoon and into the evening for northwest Colorado and northeast Utah, where 35 mph gusts and single-digit humidity could allow fire to spark and spread rapidly.
By week's end, daily high temperature records could fall in parts of the West, where places like Denver could top 100 degrees.
Bracing for the season's first heat wave
Starting on Sunday, the hot weather will invade the Midwest and parts of the Southeast. The heat index is forecast to make it feel like more than 100 degrees in Chicago, Louisville and Nashville.
By Monday, record-breaking daily high temperatures are expected to be widespread across the Mid-Atlantic and Northeast, with highs from the mid-90s to the low-100s.
High humidity will make conditions more stifling for tens of millions of people. The heat index, a measure of what the temperature feels like, is expected to rise to the low to mid-100s in New York City, Boston and Washington, D.C., on Monday and extend into next week.
During the heat wave, nighttime temperatures are expected to only drop into the 70s, meaning that without adequate air conditioning this heat wave will be extremely dangerous for many Americans.
The dangerous heat in the Northeast is not expected to subside until late next week, when clouds and rain will move into the region.
