Ragweed is very low in Charleston today.

No mold level

Google’s index covers tree, grass and weed pollen only, so there is no mold level for Charleston on this page. The National Allergy Bureau publishes pollen and mold counts measured at its stations. Our guides cover common molds such as Alternaria, Cladosporium and Aspergillus.

No indoor allergens

The forecast doesn’t cover allergens indoors either: dust mites, cockroaches, mice, cats and dogs. Our guides explain each one, starting with dust mites and cats.

Asthma in Charleston

An estimated 8.8% of adults in the city of Charleston have current asthma, according to the CDC’s PLACES estimate for 2023 (95% confidence interval: 7.9% to 9.8%). It is a statistical estimate from national survey data, not a count.

Allergists in the Charleston area

18 allergists enrolled in Medicare practice in the Charleston area: 2.02 for every 100,000 people, more than the 1.22 across the US. The count doesn’t show how soon you can get an appointment. See the doctors listed in the Charleston area, or how every state and metro compares.

AllergyNest count from CMS’s Doctors and Clinicians file (October 2026) and Census population estimates for 2025.

Sea-breeze thunderstorms bring slightly higher precipitation to South Carolina’s Coastal Plain, and the coastal Lowcountry averages 45 to 55 inches a year.² At Charleston International Airport, winters average about 52 °F, and a typical year has about 266 days between the last spring freeze and the first fall freeze.¹

Live oak made up 23.8 percent of the 15,244 publicly managed street trees in Charleston’s inventory when Forest Service researchers analyzed it in 2006.³ Crapemyrtle came next at 20.1 percent, followed by sabal palmetto at 19.6 percent.³ In South Carolina, live oak grows in dry sandy woods, moist rich woods and wet woods, and across its range it flowers every spring from March through May.⁴ Clemson Extension says pine trees, which rely on the wind to deliver their pollen, produce most of the yellow-green coating seen from late March through April.⁵

Clemson Extension lists two ragweeds in South Carolina, common ragweed and giant ragweed, with common ragweed appearing to be the more prevalent.⁶ Ragweed pollen is carried by the wind, and the ragweeds bloom alongside the state’s goldenrods, which typically begin in mid-to-late August and often last into early October.⁶