Record-threatening heat wave headed toward D.C.

A heatwave centered across the Southwest is sliding eastward, affecting D.C. and East Coast cities through next week — and possibly longer.

Why it matters: Extreme heat is the top weather-related killer in the U.S. And a heat wave this time of year carries heightened health risks since people are not yet accustomed to the high temperatures.

Zoom in: The D.C. area will experience an "appetizer round of heat" Thursday and Friday, according to the Capital Weather Gang , with temperatures reaching near 90°F — the hottest this year after a largely comfortable spring.

• The worst heat is expected to start mid-to-late next week with highs that could reach the mid-90s. Humidity levels are projected to rise, and parts of the area may see heat indexes (how temperatures feel, factoring in humidity) of at least 105°F.
• This heat could threaten records, and possibly yield the first 100°F day in D.C. since 2016.

Context: Climate change greatly increases the likelihood of heatwaves , as well as their intensity and duration.

The big picture: A large area of high pressure, also known as a heat dome, is building over much of the Central and Eastern half of the country into next week, computer models and NWS forecasts show.

• The Climate Prediction Center estimates the heat threat is likely to continue across the East through the end of June.

Threat level: The latest computer model projections for the summer show an overall tilt toward hotter-than-average conditions across the country.

What we're watching: With heat indexes that could reach 110°F, jurisdictions around the DMV may issue heat advisories or warnings, cancel outdoor activities, and activate cooling centers .