Get the latest forecast from Meteorologist Tom Kierein
Temperatures are expected to be near 100 degrees Wednesday and Thursday, but heat has already claimed the lives of two people in Maryland.
A Cecil County man and an Anne Arundel County woman, both 65 or older, died within the past 10 days from excess heat exposure, according to the Maryland Department of Health and Mental Hygiene.
Both victims had underlying medical conditions.
While the temperature reached 90 degrees in most of the D.C. region Tuesday, temperatures will rise even more today and tomorrow.
A heat advisory has been issued for the D.C. region from noon to 8 p.m. Wednesday. NBC Washington chief meteorologist Doug Kammerer said Wednesday's high could reach 98 degrees, while Thursday's high could hit 99.
Heat indexes both days are expected to be between 100 and 105 during the hottest part of the day. Clean Air Partners said that the air quality rating for both days is unhealthy, meaning that pollution levels will be harmful to children, older adults and anyone with a respiratory or heart condition.
Because of the heat and poor air quality in the forecast, D.C. trash and recycling crews will being collection an hour earlier -- at 6 a.m. -- on Wednesday and Thursday. Residents can put their trash out beginning at 6 p.m. Tuesday and again Wednesday to avoid disturbing their usual morning routines.
Wednesday's record high of 98 was set in 1999, while Thursday's record high of 102 was set all the way back in 1874.
Temperatures will decrease slightly on Friday, as the high is expected to reach 93 with isolated thunderstorms. Temperatures will decrease to the mid- to upper 80s Saturday and Sunday with chances of thunderstorms.
The DHMH said that heatstroke and heat exhaustion can develop from the hot and humid conditions typically associated with D.C.-area summers.
Heatstroke is a serious illness characterized by a body temperature greater then 105 degrees. Symptoms may include dry red skin, convulsions, disorientation, delirium and coma. Onset of heatstroke can be rapid: a person can go from feeling apparently well to a seriously ill condition within minutes. Treatment of heatstroke involves the rapid lowering of body temperature, using a cool bath or wet towels. A heatstroke victim should be kept in a cool area; emergency medical care should be obtained by dialing 911.
Heat exhaustion is a milder form of heatstroke that may develop due to a combination of several days with high temperatures and dehydration in an individual. Signs of heat exhaustion include extreme weakness, muscle cramps, nausea, or headache. Victims may also vomit or faint. Heat exhaustion is treated with plenty of liquids and rest in a cool, shaded area. Those on a low-sodium diet or with other health problems should contact a doctor.
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