New York City is expected to experience rapidly rising temperatures this week as a heat dome settles over the region, with highs forecast to reach 100 degrees by Thursday and Friday. The National Weather Service (NWS) has issued an extreme heat watch beginning Wednesday afternoon, warning of sustained hot conditions through the Independence Day holiday weekend.

Temperatures are projected to climb from a high of 88 degrees on Tuesday to the mid-90s on Wednesday before soaring into triple digits later in the week. While there is a slight chance of thunderstorms Tuesday night and a 20% chance of rain Wednesday afternoon, the overall trend points toward a prolonged period of significant heat.

Meteorologists describe the heat dome as a persistent area of high pressure trapping heat near the surface, causing temperatures to build over several days. According to the National Oceanic and Atmospheric Administration, this phenomenon can last from days to weeks. NWS meteorologist Alex Lamers compared the process to a lid on a pot, where heat accumulates beneath a stationary high-pressure system in the upper atmosphere.

Officials caution that the intense heat will affect outdoor activities, including celebrations for Independence Day on Friday, when many federal and state agencies observe the holiday. The heat is also expected to impact fans attending the FIFA World Cup round of 16 match at MetLife Stadium on Sunday. While forecasted to reach around 89 degrees, the match is bracketed by potential thunderstorms Saturday and Sunday nights, which may offer some relief.

City health authorities highlight the dangers posed by the heat, noting that more than 500 New Yorkers die annually due to heat-related causes. Residents are advised to wear light clothing, apply sunscreen, stay hydrated, and seek shaded areas when outside. For those needing respite from the heat, New York City’s 311 service and website provide information on available cooling centers.