Visitors should be aware of the possibility of dangerous heat Myrtle Beach as the holiday approaches.

The National Weather Service forecast office in Wilmington, which covers Horry County, is framing the stretch from this weekend through the July 4 holiday week in two tiers. For the weekend of June 27 and 28, NWS forecasts heat indices “close to (or exceeding) heat advisory thresholds” with a rising chance of showers and thunderstorms. For late next week — the window that includes Independence Day — NWS Wilmington’s June 25 Area Forecast Discussion states plainly: “Dangerous heat remains possible next week, including the potential for dangerous heat Myrtle Beach.” NOAA’s Climate Prediction Center also favors above-normal temperatures through the holiday.

No Heat Advisory or Excessive Heat Warning is currently in effect for Horry County. The last advisory expired June 18. The “dangerous heat” language is a forward-looking forecaster judgment about cumulative multi-day heat — not a triggered advisory product.

July 4, 2026 falls on Saturday, and the Myrtle Beach Area is heading into one of its highest-traffic weeks. Specific 2026 visitor projections are 400 thousand plus across the Grand Strand.

Peak visitor load, multiple outdoor events, and forecaster language calling cumulative heat “dangerous” are why MyrtleBeachSC is publishing this guide now rather than waiting for an advisory.

What NWS Is Saying

Understanding the Risks of Dangerous Heat Myrtle Beach

The June 25 NWS Wilmington Area Forecast Discussion carries two Key Messages for Horry County. Key Message 1, on the weekend: “Heat and humidity returns for the weekend. Rain chances increase as well.” Key Message 2, verbatim on next week: “Dangerous heat remains possible next week, and residents should prepare for dangerous heat Myrtle Beach during this period.” The discussion also describes the late-next-week stretch as “prolonged and dangerous heat through the period” — the forecaster’s word, applied to the cumulative effect of multiple consecutive hot days, not the immediate weekend.

For the weekend, the AFD softer-frames conditions as “close to (or exceeding) heat advisory thresholds across the region each day,” with temperatures in the upper 90s to near 100. NWS is distinguishing weekend conditions (hot, advisory-borderline, with storms) from late-next-week conditions (prolonged and dangerous heat).

The same discussion forecasts heat indices “around 100” across the Grand Strand for the weekend of June 27 and 28. Heat index combines air temperature and humidity to estimate the apparent temperature on the body; coastal Horry’s humid marine air routinely pushes it several degrees above the thermometer reading.

Under NWS Wilmington’s local criteria, a Heat Advisory is issued when heat indices are expected to reach 105 to 109 degrees for two or more hours. An Excessive Heat Watch or Warning requires forecast heat indices of 110 degrees or higher for two or more hours. The 105-degree threshold is specific to the Wilmington office — higher than the 100-degree default used elsewhere.

Heat indices around 100 this weekend, on their own, do not meet the advisory threshold. The NWS discussion is flagging the multi-day cumulative load — overnight lows that don’t recover, dehydration that compounds, exposure that adds up. NWS will issue an advisory if conditions reach those thresholds. As of Thursday, June 25, no such product is in effect.

The June 25 AFD also adds weekend rain chances not in earlier discussions. Myrtle Beach is forecast for a 35 percent chance of showers and thunderstorms Saturday and 52 percent Sunday. NWS attributes the increase to a backdoor cold front arriving late Sunday and notes “a strong wind gust will be possible with a few storms” Sunday evening due to dry air aloft. Outdoor-event planners should account for storm risk Sunday evening alongside the heat.

The Point-Forecast Picture

NWS point forecasts show coastal and inland Horry on different curves.

In **Myrtle Beach**, highs are 92 Saturday June 27, 93 Sunday June 28, 89 Monday, 89 Tuesday, 90 Wednesday July 1. Weekend overnight lows stay in the high 70s — 79 Saturday night, 77 Sunday night per the June 25 forecast — and warm nights are part of what makes multi-day heat harder on the body.

**North Myrtle Beach** runs a degree or two warmer: 92 Saturday, 94 Sunday, 90 Monday, 90 Tuesday, 91 Wednesday.

**Conway**, inland, runs hotter still: 97 Saturday, 98 Sunday, 94 Monday, 94 Tuesday, 96 Wednesday — closer to advisory territory on air temperature alone, before humidity.

**Murrells Inlet** (NWS Charleston coverage): 94 Saturday, 95 Sunday, 90 Monday.

The coastal-versus-inland gap matters: a reader in Aynor or Loris will feel afternoons several degrees hotter than one at the Pier.

July 4 Itself, and the Limits of Long-Range Forecasting

Saturday, July 4 is day 9 from this publication. NWS point forecasts carry high confidence out to about seven days and degrade past that. Specific high temperatures for July 4 are projected to be in the mid 90’s.

What is verified is the longer-range outlook. NOAA’s Climate Prediction Center 6-10 day outlook (June 30 through July 4) and its 8-14 day outlook (July 2 through July 8) both favor above-normal temperatures for Horry County.

The honest read for July 4 planning: the climate signal is leaning hot; day-by-day specifics aren’t pin-down-able yet. Plan as if it will be hot and check the updated forecast again Monday.

What “Dangerous” Means in Heat Terms

Heat is the deadliest weather hazard in the U.S. in a typical year, per the CDC, which attributes roughly 1,220 heat-related deaths nationally per year. Horry-specific 2024 and 2025 heat-related ER visit and death counts are `[UNVERIFIED]`.

According to the CDC, **heat exhaustion** presents as heavy sweating; cool, pale, clammy skin; a fast, weak pulse; muscle cramps; dizziness; headache; nausea; and fainting. CDC guidance: move the person to a cool place, loosen clothing, apply cool wet cloths, offer sips of water. If symptoms persist beyond an hour, seek medical help.

**Heat stroke** is the medical emergency. CDC signs include body temperature of 103 degrees or higher; hot, red, dry or damp skin; a fast strong pulse; confusion; loss of consciousness. The CDC’s instruction is direct: call 911 immediately, move the person to a cooler place, and lower body temperature with cool cloths or a cool bath. Do not give a person experiencing heat stroke anything to drink.

The CDC identifies higher-risk groups: adults 65 and over, children under 5, outdoor workers, the chronically ill, and people on certain medications. Horry County skews older than the state average, so the 65-plus share is larger here than statewide. Visitors from cooler climates are typically not heat-acclimated; the body takes one to two weeks to adapt.

Beach and Outdoor Event Safety

The marine forecast for the holiday window is relatively benign. Ocean water is around 81 degrees and climbing toward the low 80s by July 4. Winds variable, south-southwest at 7-12 knots, seas 1-3 feet. Rip current risk for July 4 is low to moderate. No beach hazards statement is in effect.

The UV index along coastal South Carolina in late June and early July routinely reaches 10 to 11 — very high to extreme. The dominant beach-safety story for this stretch is not waves but sun. NWS and CDC guidance: SPF 30 or higher, reapply every two hours and after swimming; wide-brimmed hat and UV-protective clothing; shade between 10 a.m. and 4 p.m. UV reflects off sand and water and reaches skin even in shade.

For outdoor holiday events — fireworks shows, beach gatherings, parades, 5K races — heat-safety runs alongside the crowd-and-traffic calculus. Crowds waiting for evening fireworks remain exposed to residual heat after sunset; humid high-80s air holds near 80 well into the night. Morning timing on parade routes and early-start races helps but does not eliminate exposure.

Practical Guide for Residents and Visitors

The following guidance is consolidated from CDC and NWS.

**Hydrate before you are thirsty.** Thirst is a lagging indicator. Water is the default; sports drinks help when sweating is heavy and sustained. Limit alcohol and caffeine outdoors.

**Treat 10 a.m. to 4 p.m. as the peak-heat window.** Schedule yard work, exercise, and long beach sessions for morning or late afternoon.

**Never leave children or pets in vehicles, even briefly.** Per NWS, a car interior can rise more than 20 degrees in 10 minutes. The risk is fatal.

**Check on neighbors at higher susceptibility** — older adults living alone, the homebound, anyone without reliable air conditioning.

**Pavement and sand burn paws.** If asphalt is too hot for the back of your hand for five seconds, it is too hot for a dog. Walk pets early or late.

**Know the warning signs.** Heat exhaustion needs cooling and rest. Heat stroke — high body temperature, confusion, loss of consciousness — needs 911.

**Acclimatize.** Visitors from cooler climates: build outdoor time gradually rather than spending all day on the beach the first day.

Horry County Resources

Horry County Emergency Management coordinates the county’s heat response and publishes alerts through its public channels. Cooling-center activation status for the current period is `[UNVERIFIED]`; residents needing cooled shelter should call 211 or check the county Emergency Management page before traveling to any listed site.

Santee Cooper’s Community Cares program, run with United Way of Horry County, provides utility assistance for residents at risk of disconnection during hot-weather periods. The South Carolina Department of Public Health maintains a heat-related illness page. For emergencies — suspected heat stroke, a child or pet trapped in a vehicle, a beach collapse — call 911.

The Forecast Will Tighten

NWS Wilmington’s June 25 AFD is doing two things at once. For the immediate weekend, it positions the heat as advisory-borderline — “close to (or exceeding) heat advisory thresholds” — paired with rising rain chances and a gusty-storm risk Sunday evening. For late next week, the AFD names the risk plainly: “Dangerous heat remains possible next week.”

NWS will issue a Heat Advisory or Excessive Heat Warning if forecast heat indices cross the 105-degree threshold for two or more hours. Until then, the forecast is the planning tool. Hydrate, schedule around the peak window, watch the people most at risk, plan for storm risk Sunday evening if you’re outside, and check the forecast again before stepping outside Saturday morning.

Further Reading

Dangerous heat Myrtle Beach– NWS Wilmington forecast office: https://www.weather.gov/ilm/

Dangerous heat Myrtle Beach – NWS Wilmington Area Forecast Discussion: https://forecast.weather.gov/product.php?site=NWS&issuedby=ILM&product=AFD

Dangerous heat Myrtle Beach – NWS Wilmington Non-Precipitation Weather product: https://forecast.weather.gov/product.php?site=NWS&issuedby=ILM&product=NPW

Dangerous heat Myrtle Beach – NWS Wilmington local heat thresholds: https://www.weather.gov/ilm/heat

Dangerous heat Myrtle Beach – Myrtle Beach 7-day point forecast: https://forecast.weather.gov/MapClick.php?lat=33.6988&lon=-78.8922

Dangerous heat Myrtle Beach – NOAA Climate Prediction Center 6-10 day outlook: https://www.cpc.ncep.noaa.gov/products/predictions/610day/

Dangerous heat Myrtle Beach – NOAA Climate Prediction Center 8-14 day outlook: https://www.cpc.ncep.noaa.gov/products/predictions/814day/

Dangerous heat Myrtle Beach – NWS HeatRisk index: https://www.wpc.ncep.noaa.gov/heatrisk/

Dangerous heat Myrtle Beach – CDC heat-related illnesses: https://www.cdc.gov/niosh/heat-stress/about/illnesses.html

Dangerous heat Myrtle Beach – NWS heat illness reference: https://www.weather.gov/safety/heat-illness

Dangerous heat Myrtle Beach – South Carolina Department of Public Health, heat-related illness: https://dph.sc.gov/health-wellness/health-safety/heat-related-illnesses

Dangerous heat Myrtle Beach – Horry County Emergency Management: https://www.horrycountysc.gov/departments/emergency-management/

Dangerous heat Myrtle Beach – AccuWeather Myrtle Beach forecast: https://www.accuweather.com/en/us/myrtle-beach/29577/weather-forecast/331909