🦀 Baltimore Weather

Under the Chesapeake's moderating hand

Baltimore's weather is shaped by a tug-of-war between the warm, humid South and the colder Northeast, refereed by the nearby Chesapeake Bay. The Bay moderates the city's temperatures year-round — taking a little heat off summer afternoons with a "bay breeze" and trimming the edge off winter cold — while keeping humidity high through the warm months.

Hot, muggy summers

Baltimore has a humid subtropical climate, and July and August are hot and sticky, with highs in the upper 80s°F (around 31°C) and oppressive humidity that regularly drives the heat index past 100°F (38°C). Afternoon and evening thunderstorms are frequent, occasionally turning severe. The all-time record high is 108°F (42°C).

Mild but unpredictable winters

Winters are relatively mild, with highs in the low-to-mid 40s°F (around 5–7°C), but Baltimore sits close enough to the rain–snow line that snowfall varies enormously year to year. A quiet winter might bring a few inches; a big one, like February 2010's back-to-back blizzards, can bury the city in two feet.

The city averages about 44 inches (1,120 mm) of precipitation annually. Spring and fall are pleasant and comfortable, with autumn typically the driest, most settled season.

Bay humidity between North and South

Baltimore sits on a climatic seam between the humid North and the subtropical South, moderated by the Chesapeake Bay. The bay adds moisture to already-sticky summers and delays autumn's chill, while the harbor's urban core runs several degrees warmer than the outer suburbs.

Winters are variable and often a battleground: coastal storms can deliver anything from cold rain to a crippling nor'easter blizzard, decided by a narrow margin of temperature. Summer brings frequent thunderstorms and the occasional tropical remnant sweeping up the coast with heavy rain.