Air Quality in Mount Pleasant, South Carolina — Live

Live readings from PurpleAir sensors across Mount Pleasant — with free alerts the moment the air changes.

Live Mount Pleasant AQI from nearby PurpleAir sensors loads when this page opens in a browser, along with a live sensor map covering Mount Pleasant and Sullivan's Island, Isle of Palms, Awendaw, Daniel Island.

Mount Pleasant sits on a peninsula east of Charleston Harbor, and the sea breeze that comes with that location does real work: most days here run Good or Moderate, and the town avoids the worst of the ozone problems that build up in landlocked parts of the Southeast. The exceptions are specific and local — still, hot summer afternoons when ozone can climb, cooler-season days when smoke drifts in from prescribed burns in the Francis Marion National Forest just up Highway 17, and the rare summer when wildfire smoke from as far away as Canada reaches the South Carolina coast, as it did more than once in 2023.

Canairy watches the sensors around your home, your kids' school, and everywhere else you care about, and tells you in plain English when the air changes enough to matter.

The sea breeze keeps most days clean

Mount Pleasant occupies a peninsula pinched between the Wando and Cooper rivers, and that geography rarely goes long without an onshore breeze off the Atlantic. That steady marine air is the single biggest reason the town's ozone and particle readings tend to run better than inland parts of the Lowcountry — there's usually enough wind moving through to keep pollution from settling.

But the same flat, low-relief coastline that lets the breeze in has nothing to interrupt airflow when that breeze fails. When summer high pressure stalls and winds go slack for a few days in July and August, heat and humidity cook up ground-level ozone the same way they do across the rest of the Southeast, and that's when Mount Pleasant is most likely to see a Moderate or Unhealthy for Sensitive Groups reading.

Prescribed burns from the Francis Marion National Forest send smoke into town

Mount Pleasant's Highway 17 corridor runs roughly 24 miles from the Old Village north to Awendaw, and just off that road sits the Francis Marion National Forest — hundreds of thousands of acres of pine and pocosin that the US Forest Service treats with prescribed fire most years. Recent burn seasons have covered roughly 50,000 planned acres across the forest in Charleston and Berkeley counties, including tracts near Highway 41 and the Wando area, a few miles from Mount Pleasant's northern neighborhoods.

These are managed fires, set mostly in the cooler, more humid months when smoke behaves predictably — not wildfires. But planned doesn't mean invisible: the Forest Service's own burn notices routinely warn that smoke will drift toward Highway 17 or Highway 41 depending on the day's wind, and the plumes are hardest to spot from satellite in the morning and easiest to see by afternoon. A backyard in Park West or Carolina Park can smell like a campfire on a burn day even though nothing nearby is actually on fire.

Port traffic on Long Point Road is an everyday, local source

The Wando Welch Terminal, the SC Ports Authority's container port, sits inside Mount Pleasant town limits at the end of Long Point Road. A Phase II expansion has pushed the terminal's capacity past 5 million containers a year, and because the terminal was built without an on-site rail yard, containers bound for rail have to be trucked roughly 12 miles to North Charleston — funneling a steady stream of diesel trucks through the Long Point Road and I-526 corridor.

The federal government has put roughly $195 million toward rebuilding the I-526/Long Point Road interchange specifically to ease that truck bottleneck, which is a fair measure of how much local traffic the port now generates. It doesn't put Mount Pleasant in the same category as North Charleston's industrial peninsula, but it's a real, everyday layer of diesel exhaust layered on top of the ozone and smoke story, concentrated along Long Point Road rather than spread evenly across town.

Mount Pleasant air quality FAQ

What is the air quality in Mount Pleasant right now?

This page shows the current AQI for Mount Pleasant, calculated from PurpleAir sensors across town and updated continuously. The map below shows every live sensor, so you can check the reading closest to your own neighborhood, from the Old Village to Park West.

Why does Mount Pleasant sometimes smell like smoke with no fire nearby?

Most likely a prescribed burn. The US Forest Service manages the Francis Marion National Forest just north of town with planned fire on tens of thousands of acres most years, mostly in the cooler months, and smoke can drift down Highway 17 or Highway 41 into Mount Pleasant depending on the day's wind. Canairy's live sensors will show it even before you smell it.

Does port traffic affect Mount Pleasant's air quality?

It adds a real, local layer of diesel exhaust. The Wando Welch container terminal sits at the end of Long Point Road inside town limits, and because it has no on-site rail yard, trucks haul containers roughly 12 miles to North Charleston, concentrating truck traffic — and the exhaust that comes with it — along Long Point Road and the I-526 corridor.

What AQI level is unhealthy?

Under the US EPA scale, AQI 0-50 is Good and 51-100 is Moderate. From 101 the air is Unhealthy for Sensitive Groups - kids, older adults, and people with asthma or heart conditions - and above 150 it's Unhealthy for everyone. Canairy translates these numbers into a plain-English verdict, like whether to close the windows or move a workout indoors.

Where does Canairy's Mount Pleasant data come from?

Readings come from PurpleAir's network of laser particle sensors across Mount Pleasant and surrounding towns, cross-referenced with government monitors and the Google Air Quality API. You can see every sensor behind your numbers on the live map - there's no black box.

Is Canairy free?

Yes. The Canairy app is free to download and includes live air quality for all your saved places, plain-English verdicts, and free push alerts when the air crosses your threshold. A paid plan adds extras like SMS text alerts.

Get Canairy free on Google Play.