Latest Timing For 'Ring Of Fire' Storms As Extreme Heat Lingers In PA

Another day of brutal heat will blanket the Philadelphia region Wednesday before conditions turn stormy in the evening in what forecasters are calling a "ring of fire" thunderstorm system.

Extreme heat Wednesday, unsafe conditions remain

But before the weather turns unsettled, expect high temperatures in the area to reach the upper 90s. A high temperature of 98 is predicted for Philadelphia, with heat index values as warm as 106 degrees. That's just slightly lower than Tuesday's record-breaking high temperature of 101 degrees in the city.

"There is an extreme risk of heat related illnesses through today, especially for those most vulnerable. Drink plenty of fluids, stay in an air conditioned room if possible, avoid strenuous outdoor activities during the hottest parts of the day, and check up on relatives and neighbors," the National Weather Service said in a Wednesday morning briefing.

An extreme heat warning is in place through Wednesday at 8 p.m.

'Ring of fire' storms move in

Severe weather could move in as early as Wednesday evening, causing temperatures to tick down before a noticeable change Friday, when the high temperature will linger in the low to mid 70s.

AccuWeather reports that a large swath of thunderstorms surrounding the massive heat dome that has engulfed Texas to New England could bring a "ring of fire" to the mid-Atlantic region Wednesday evening.

The pattern is referred to in the weather community as a "ring of fire" because thunderstorms form along the edges of the heat dome, AccuWeather explained. Because the heat dome is warm through most layers of the atmosphere, clouds and storms have difficulty forming.

"However, on the edges of the heat, especially along the northern and western flanks thereof, the air is cooler well above the ground, which makes it easier for clouds to tower and produce thunderstorms," AccuWeather said. "Within this ring, there can be spotty, individual thunderstorms, large clusters of thunderstorms or a solid line of storms that can repeat or meander back and forth as hot and cool air change hands."

The severe weather threat will extend into the Northeast, where the threat of locally severe thunderstorms will extend eastward through Pennsylvania and the southern tier of New York to New Jersey.

Risk of flash flooding, severe conditions

The National Weather Service says there is a marginal risk the storms will be severe, and some could bring flash flooding.

Here is the latest local forecast:

Today: Scattered showers and thunderstorms, mainly after 3pm. Sunny and hot, with a high near 98. Heat index values as high as 106. Calm wind becoming northwest around 5 mph in the afternoon. Chance of precipitation is 30%. New rainfall amounts of less than a tenth of an inch, except higher amounts possible in thunderstorms.

Tonight: A chance of showers and thunderstorms, mainly after 2am. Partly cloudy, with a low around 77. Northwest wind around 5 mph becoming calm in the evening. Chance of precipitation is 40%. New rainfall amounts between a tenth and quarter of an inch, except higher amounts possible in thunderstorms.

Thursday: A chance of showers, then showers likely and possibly a thunderstorm after 2pm. Partly sunny, with a high near 87. Northeast wind around 5 mph. Chance of precipitation is 60%. New rainfall amounts between a tenth and quarter of an inch, except higher amounts possible in thunderstorms.

Thursday night: Showers likely and possibly a thunderstorm before 2am, then a chance of showers and thunderstorms after 2am. Mostly cloudy, with a low around 66. East wind around 5 mph. Chance of precipitation is 60%. New rainfall amounts between a tenth and quarter of an inch, except higher amounts possible in thunderstorms.

Friday: A chance of showers and thunderstorms before 8am, then a chance of showers between 8am and 2pm, then a chance of showers and thunderstorms after 2pm. Cloudy, with a high near 73. East wind around 5 mph. Chance of precipitation is 30%. New rainfall amounts of less than a tenth of an inch, except higher amounts possible in thunderstorms.

Friday night: A chance of showers and thunderstorms. Mostly cloudy, with a low around 68. Chance of precipitation is 30%. New rainfall amounts between a tenth and quarter of an inch, except higher amounts possible in thunderstorms.