The Philly area’s first heat wave of the summer is upon us. Here’s what to know

From extreme heat terminology to how to stay safe and cool despite soaring temps, here's what you should know.

• By Zoe Read and Maria Pulcinella/WHYY

The Philadelphia area is expected to reach record high temperatures this week. WHYY News explains what you need to know to stay safe.

• What does the forecast say?

   

   

  This week will mark the start of a prolonged period of excessive heat, with temperatures in the mid- to upper-90s, according to the National Weather Service.

  A Heat Advisory will be in effect from 10 a.m. Tuesday to 6 a.m. Wednesday for Southeastern Pennsylvania, New Jersey and portions of northern Delaware. Heat index values up to 99 degrees are expected.

  An Excessive Heat Watch will be in effect for Southeastern Pennsylvania, New Jersey and portions of northern Delaware from Wednesday morning through Saturday evening, with dangerously hot conditions and heat index values up to 106 degrees possible.

• Where can I find information and advice about heat?

   

   

  FEMA’s “Ready.gov” website has good advice to protect yourself, your family, and your pets during heat waves.

  Philadelphia residents can sign up for free text alerts by texting READYPHILA to 888-777, while residents outside of the city can sign up for ReadyPA alerts.

  New Jersey residents can find heat safety information and tips to stay cool at the N.J. Office of Emergency Management on its website, Facebook, X or Instagram.

  New Jersey residents are encouraged to follow both the National Weather Service Mount Holly and National Weather Service N.Y., depending on their location.

  The Delaware Emergency Management Agency posts information and resources about heat on its social media pages and on PrepareDE.org.

• What can I do to protect myself and loved ones?

   

   

  Prior to a heat wave, residents can prepare by making sure window air conditioners are installed snugly, checking air-conditioning ducts for proper insulation, installing aluminum foil-covered cardboard to reflect heat back outside and by covering windows that get hit with a lot of sun.

  These five tips can help boost your air conditioner’s performance during extreme heat.

  During high temperatures, people should avoid direct sunlight and find a well-ventilated, air-conditioned place, keep hydrated, and limit outdoor activity. Those who work outside should take frequent breaks with shade and water.

  And importantly, residents should not leave children or pets in a hot car. Pets should have access to shade and water when outside and be closely watched. Residents are encouraged to eat light meals, because hot and heavy meals can heat up the body.

  During a Heat Health Emergency, Philadelphia invites residents to cool off in air-conditioned locations, such as libraries, schools, spraygrounds, pools and senior centers, which are mapped here.

  Swimming in rivers, streams and other waterways within the city is dangerous due to pollution and in some cases strong currents, and not permitted.

  New Jersey has created two websites for residents seeking help with extreme heat, heathub.nj provides information and residents can also cool off at one of the state’s cooling centers.

  In Delaware, county officials and the American Red Cross open cooling stations as needed. Residents can also go to public buildings such as libraries to get out of the heat.

• What are the health risks of extreme heat?

   

   

  Heat is the number one weather-related killer according to the EPA and the National Weather Service.

  High temperatures and humidity can cause dehydration, heat exhaustion and heatstroke.

  Symptoms could include headache, dizziness, nausea, heavy sweating, confusion, weakness and becoming unconscious.

  Those who have other health conditions, including diabetes, could be more vulnerable.

  Residents are advised to check on neighbors and the elderly, and are urged to never leave pets or children in cars, which can lead to death.

  Some areas, often referred to as “heat islands,” are particularly vulnerable because they have less green space and more cement cover. That includes parts of Philadelphia.

  An analysis by Climate Central shows some urban neighborhoods in the Philadelphia region can be at least 9° F hotter due to the heat island effect.

  “In these areas, the populations also tend to be poorer, and may be less likely to turn on air conditioning,” said Dr. Marilyn Howarth of Penn Medicine. “If they’re in a very hot environment, they’re more likely to have a heart attack, they’re more likely to have their blood pressure raised, and have a stroke.”

• What heat terms should I know?

   

   

  Heat wave
  Prolonged excessive heat, often combined with excessive humidity.

  Heat index
  A number in degrees Fahrenheit explaining how hot it feels when relative humidity is added to the air temperature.

  Excessive Heat Watch
  Weather conditions indicate a potential excessive heat event in the next 24 to 72 hours.

  Excessive Heat Warning
  Daytime temperatures are expected to be 105° or higher over the next two days.

  Heat Advisory
  The temperature is expected to go above 100° in the next 12 hours.

  Code Red
  During extremely hot weather — when the forecast includes at least three consecutive days of 95-degree Fahrenheit temperatures and above with high humidity — Philadelphia’s Office of Homeless Services will declare a Code Red.

  During a Code Red event, the city implements special measures to keep people experiencing homelessness safe. Those measures include 24-hour outreach to find unhoused people and transport them to safe indoor spaces and opening all available beds within the city’s emergency housing network for those in need.

  If residents see a person who appears unhoused during a Code Red, they are urged to request a street outreach team by contacting the city’s Homeless Outreach hotline at 215-232-1984.

  During Code Red events, all dogs must be either indoors or have access to shelter that meets the following requirements:

  Suitable size to accommodate the dog both standing and lying
  Made of durable material with a solid, moisture-proof floor raised at least two inches from the ground
  Access to drinking water available in a clean, liquid state
  Free from excessive dirt, trash and waste
  One or more areas of shade large enough to accommodate their lations of the city ordinance may result in penalties of $500 or more

  If residents see a pet outside during a Code Red, they are urged to contact Philadelphia’s Animal Care and Control Team (ACCT) at 267-385-3800 and dial 1 to speak with the dispatcher. Residents may also file a report online will all of the available information.

  ACCT also provides free straw for caretakers or owners of pets and community cats who spend most or all of their time outdoors.

  Here’s how you can keep your pet(s) safe — and comfortable — in extreme heat.

  Heat Health Emergency
  A Heat Health Emergency, which often overlaps with a Code Red, is declared by the city when the expected heat index meets thresholds that track when people go to the hospital for heat-related syndromes, according to James Garrow, a spokesperson for the Philadelphia Department of Public Health.

  An HHE declaration kicks off the city’s response to extreme heat, including extended hours at some libraries acting as cooling centers, and utility shutoff pauses.

  During a Heat Health Emergency, the city of Philadelphia urges residents to go to an air-conditioned space. If air conditioning is unavailable, residents may visit the city’s cooling centers, pools, or spraygrounds. If you must go outside amid scorching temps, here’s what to watch out for and how to stay safe.

  Residents are also encouraged to keep blinds and curtains closed during the day, open windows to let in a breeze if it cools down at night, and take cold showers or baths to help stay cool.

• What does climate change have to do with extreme heat?

   

   

  Climate change is causing hotter temperatures and an increase in extreme heat days in our region, with New Jersey being the fastest-warming state on the East Coast.

  Globally, 2023 was the hottest year on record, and the 5th warmest on record for the lower 48 states in the U.S. with daily temperatures 2.4° above average, according to NOAA. Forecasters expect 2024 to be another record-breaking year for heat.

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