Weather and climate in Baltimore (Maryland)

The climate of Baltimore, the main city of Maryland, is continental, with cold winters and hot summers.
The Delaware Peninsula separates the city from the Atlantic Ocean, however, the city overlooks an inlet of the same ocean, the Chesapeake Bay. To the north, the bay receives the waters of the Susquehanna River, while the Patapsco River flows into the sea near Baltimore.
The city is located in an area where different air masses collide: the cold ones coming from Canada and the warm ones coming from the Gulf of Mexico. The result is an unstable climate, with waves of bad weather alternating with clear and sunny days. The wind blows frequently as well.
The average temperature of the coldest month (January) is of 1.3 °C (34 °F), that of the warmest month (July) is of 25.7 °C (78 °F). Here are the average temperatures.

Precipitation amounts to 1,145 millimeters (45 inches) per year: it is therefore quite abundant. It ranges from 75 mm (3 in) in the driest month (February) to 115 mm (4.5 in) in the wettest ones (July, September). Here is the average precipitation.

Winter, from December to February, is cold: the average temperature is just above freezing (0 °C or 32 °F), but cold spells, during which the temperature can drop to about -10/-15 °C (5/14 °F), are not rare. The wind chill can make the air feel colder than it actually is.
The coldest record is -22 °C (-7.5 °F), recorded in February 1934 and in January 1963.
Snowfalls are frequent, and sometimes can be abundant. On average, 49 centimeters (19 inches) of snow fall annually. However, sometimes the city is located just south of the area where it snows (for example, it may snow in New York and not in Baltimore).
On other occasions, the wind can blow from the south, bringing some mild days, with highs around 12/15 °C (54/59 °F). There are also clear and sunny days, with cold nights, and daytime temperatures mild or in any case acceptable.

In spring, from March to May, the weather continues to be unstable: the first warm days alternate with the return of cold weather. In March, it can snow, and this can sometimes happen still in early April. But already in April, the temperature can sometimes exceed 25 °C (77 °F). By May, the average temperature becomes pleasant, although there can still be cool days, or even a little cold and rainy, while the first heat waves can bring the temperature above 30 °C (86 °F). On sunny days, the first afternoon thunderstorms can erupt.

Summer, from June to August, is hot and humid, especially in July and August. There can be days with pleasant temperatures, around 25/27 °C (77/81 °F), maybe with some rain, but more often, there are hot and sultry days, with highs around 30 °C (86 °F). On sunny days, thunderstorms can occur in the afternoon.
Sometimes, even heat waves occur, when the temperature reaches 36/38 °C (97/100 °F), and remains high at night, around 23/25 °C (73/77 °F) or above. The record is 41 °C (106 °F), recorded in July 2011.

Autumn, from September to November, is milder and less unstable than the other seasons, at least in the first part. In early September, the weather is often still characterized by heat and humidity, with sunshine and some afternoon thunderstorms, then it quickly becomes mild and relatively quiet until mid-October, while in the second half of October, the first cold days may occur. November is by now a cold month, during which the first snowfalls may occur. There is a moderate amount of rainfall also in autumn, but it is still the season in which rainy days are a little less frequent.



On average, there are around 2,580 sunshine hours per year. Even though winter is cold, the sun shines half the time. Here are the average sunshine hours per day.

In the Chesapeake Bay, the sea temperature ranges between 4.5 °C (40 °F) and 23.5 °C (74 °F). During the most intense cold spells, the sea in the bay can freeze, especially in the northern part, where Baltimore is located. In January 1977, you could walk under the Chesapeake Bay Bridge, 35 km (21 mi) further south, near Annapolis.Here are the average sea temperatures.

Best Time

The best times to visit Baltimore are spring and autumn, in order to avoid both the winter cold and the summer heat, and in particular, the month of May and from mid-September to mid-October. June is often a good month as well, but sometimes it can be hot. In early September, the weather can be sticky, though not as hot as in midsummer. In April, it can sometimes be cold and the weather can be unstable, especially at the beginning of the month, while the second half of the month is usually mild.

Baltimore - Weather by month

Based on the period 1991-2020

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January, the coldest month of the year, is generally a cold month. The average temperature is of 1.3 °C (34 °F), with a minimum of -3.7 °C (25.4 °F) and a maximum of 6.2 °C (43.2 °F).
On the coldest nights of the month, the temperature usually drops to around -12.5 °C (9 °F). However, it dropped to -20.6 °C (-5.1 °F) in January 1994.
On the warmest days of the month, the temperature usually reaches around 18 °C (65 °F). However, it reached 22.2 °C (72 °F) in January 1993.
Precipitation amounts to 80 mm (3.1 in), distributed over 10 days.
The day lasts on average 9 hours and 50 minutes.
There are on average 5 hours of sunshine per day. So, the sun shines 51% of the time.
The average humidity is 65%.
The average wind speed is 12 kph (8 mph).
The average sea temperature is of 5 °C (41 °F). Therefore, the sea is very cold for swimming.

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February is generally a cold month. The average temperature is of 2.6 °C (37 °F), with a minimum of -2.8 °C (26.9 °F) and a maximum of 8 °C (46.4 °F).
On the coldest nights of the month, the temperature usually drops to around -11 °C (12 °F). However, it dropped to -18.4 °C (-1.1 °F) in February 1996.
On the warmest days of the month, the temperature usually reaches around 19 °C (66.5 °F). However, it reached 26.1 °C (79 °F) in February 2000.
Precipitation amounts to 75 mm (3 in), distributed over 9 days.
The day lasts on average 10 hours and 50 minutes.
There are on average 6 hours of sunshine per day. So, the sun shines 54% of the time.
The average humidity is 61%.
The average wind speed is 13 kph (8 mph).
The average sea temperature is of 5 °C (40.5 °F). Therefore, the sea is very cold for swimming.

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March is generally a quite mild month. The average temperature is of 6.9 °C (44 °F), with a minimum of 1.1 °C (33.9 °F) and a maximum of 12.7 °C (54.8 °F).
On the coldest nights, which normally occur at the beginning of the month, the temperature usually drops to around -7.5 °C (19 °F). However, it dropped to -15.6 °C (3.9 °F) in March 2014.
On the warmest days, which normally occur at the end of the month, the temperature usually reaches around 24.5 °C (76 °F). However, it reached 31 °C (87.8 °F) in March 1998.
Precipitation amounts to 100 mm (3.9 in), distributed over 11 days.
The day lasts on average 12 hours and 0 minutes.
There are on average 7 hours of sunshine per day. So, the sun shines 58% of the time.
The average humidity is 59%.
The average wind speed is 13 kph (8 mph).
The average sea temperature is of 4.5 °C (40.5 °F). Therefore, the sea is very cold for swimming.

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April is generally a mild month. The average temperature is of 12.8 °C (55 °F), with a minimum of 6.4 °C (43.6 °F) and a maximum of 19.2 °C (66.5 °F).
On the coldest nights, which normally occur at the beginning of the month, the temperature usually drops to around -1.5 °C (29.5 °F). However, it dropped to -4.4 °C (24.1 °F) in April 2016.
On the warmest days, which normally occur at the end of the month, the temperature usually reaches around 30 °C (86 °F). However, it reached 34 °C (93.2 °F) in April 2002.
Precipitation amounts to 85 mm (3.3 in), distributed over 11 days.
The day lasts on average 13 hours and 20 minutes.
There are on average 7.5 hours of sunshine per day. So, the sun shines 58% of the time.
The average humidity is 59%.
The average wind speed is 13 kph (8 mph).
The average sea temperature is of 7 °C (44.5 °F). Therefore, the sea is very cold for swimming.

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May is generally a very mild month. The average temperature is of 18 °C (64 °F), with a minimum of 11.8 °C (53.3 °F) and a maximum of 24.2 °C (75.5 °F).
On the coldest nights, which normally occur at the beginning of the month, the temperature usually drops to around 4 °C (39 °F). However, it dropped to -0.6 °C (30.9 °F) in May 1996.
On the warmest days, which normally occur at the end of the month, the temperature usually reaches around 32.5 °C (91 °F). However, it reached 36.7 °C (98.1 °F) in May 1991.
Precipitation amounts to 100 mm (3.9 in), distributed over 12 days.
The day lasts on average 14 hours and 25 minutes. So the days are long.
There are on average 8 hours of sunshine per day. So, the sun shines 57% of the time.
The average humidity is 66%.
The average wind speed is 11 kph (7 mph).
The average sea temperature is of 9 °C (48.5 °F). Therefore, the sea is very cold for swimming.

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June is generally a warm to hot month. The average temperature is of 23.1 °C (73 °F), with a minimum of 17 °C (62.6 °F) and a maximum of 29.1 °C (84.4 °F).
On the coldest nights, which normally occur at the beginning of the month, the temperature usually drops to around 9.5 °C (49 °F). However, it dropped to 5 °C (41 °F) in June 2001.
On the warmest days, which normally occur at the end of the month, the temperature usually reaches around 35.5 °C (96 °F). However, it reached 39.4 °C (102.9 °F) in June 2012.
Precipitation amounts to 100 mm (3.9 in), distributed over 11 days.
The day lasts on average 14 hours and 55 minutes. So the days are long. June 21, the summer solstice, is the longest day of the year in the Northern Hemisphere.
There are on average 9 hours of sunshine per day. So, the sun shines 62% of the time.
The average humidity is 67%.
The average wind speed is 10 kph (6 mph).
The average sea temperature is of 16 °C (61 °F). Therefore, the sea is cold for swimming.

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July, the hottest month of the year, is generally a warm to hot month. The average temperature is of 25.7 °C (78 °F), with a minimum of 19.8 °C (67.7 °F) and a maximum of 31.6 °C (88.8 °F).
On the coldest nights of the month, the temperature usually drops to around 14 °C (57.5 °F). However, it dropped to 10 °C (50 °F) in July 2001.
On the warmest days of the month, the temperature usually reaches around 36.5 °C (98 °F). However, it reached 41.1 °C (106 °F) in July 2011.
Precipitation amounts to 115 mm (4.5 in), distributed over 10 days.
The day lasts on average 14 hours and 35 minutes. So the days are long.
There are on average 9.5 hours of sunshine per day. So, the sun shines 64% of the time.
The average humidity is 67%.
The average wind speed is 9 kph (6 mph).
The average sea temperature is of 21.5 °C (71 °F). Therefore, the sea is cool for swimming.

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August is generally a warm to hot month. The average temperature is of 24.5 °C (76 °F), with a minimum of 18.8 °C (65.8 °F) and a maximum of 30.3 °C (86.5 °F).
On the coldest nights of the month, the temperature usually drops to around 13 °C (55.5 °F). However, it dropped to 7.2 °C (45 °F) in August 1992.
On the warmest days of the month, the temperature usually reaches around 35.5 °C (96 °F). However, it reached 39 °C (102.2 °F) in August 2007.
Precipitation amounts to 105 mm (4.1 in), distributed over 10 days.
The day lasts on average 13 hours and 35 minutes.
There are on average 8.5 hours of sunshine per day. So, the sun shines 63% of the time.
The average humidity is 70%.
The average wind speed is 9 kph (5 mph).
The average sea temperature is of 23.5 °C (74 °F). Therefore, the sea can be considered barely acceptable for swimming.

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September is generally a warm month. The average temperature is of 20.7 °C (69 °F), with a minimum of 14.9 °C (58.8 °F) and a maximum of 26.5 °C (79.7 °F).
On the coldest nights, which normally occur at the end of the month, the temperature usually drops to around 7.5 °C (45.5 °F). However, it dropped to 4 °C (39.2 °F) in September 2000.
On the warmest days, which normally occur at the beginning of the month, the temperature usually reaches around 33 °C (91 °F). However, it reached 36.7 °C (98.1 °F) in September 1991.
Precipitation amounts to 115 mm (4.5 in), distributed over 9 days.
The day lasts on average 12 hours and 25 minutes.
There are on average 7.5 hours of sunshine per day. So, the sun shines 60% of the time.
The average humidity is 71%. Hence, the air is normally humid.
The average wind speed is 10 kph (6 mph).
The average sea temperature is of 21 °C (70 °F). Therefore, the sea is cool for swimming.

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October is generally a mild month. The average temperature is of 14.1 °C (57 °F), with a minimum of 8.1 °C (46.5 °F) and a maximum of 20.2 °C (68.3 °F).
On the coldest nights, which normally occur at the end of the month, the temperature usually drops to around 0.5 °C (33 °F). However, it dropped to -3.3 °C (26.1 °F) in October 2001.
On the warmest days, which normally occur at the beginning of the month, the temperature usually reaches around 29 °C (84 °F). However, it reached 36.7 °C (98.1 °F) in October 2019.
Precipitation amounts to 100 mm (3.9 in), distributed over 9 days.
The day lasts on average 11 hours and 5 minutes.
There are on average 6.5 hours of sunshine per day. So, the sun shines 60% of the time.
The average humidity is 71%. Hence, the air is normally humid.
The average wind speed is 10 kph (6 mph).
The average sea temperature is of 15 °C (59 °F). Therefore, the sea is cold for swimming.

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November is generally a quite mild month. The average temperature is of 8.3 °C (47 °F), with a minimum of 2.5 °C (36.5 °F) and a maximum of 14.1 °C (57.3 °F).
On the coldest nights, which normally occur at the end of the month, the temperature usually drops to around -5 °C (23 °F). However, it dropped to -7.8 °C (18 °F) in November 1991.
On the warmest days, which normally occur at the beginning of the month, the temperature usually reaches around 23.5 °C (74.5 °F). However, it reached 27.2 °C (81 °F) in November 2003.
Precipitation amounts to 80 mm (3.1 in), distributed over 8 days.
The day lasts on average 10 hours and 0 minutes.
There are on average 5.5 hours of sunshine per day. So, the sun shines 53% of the time.
The average humidity is 66%.
The average wind speed is 11 kph (7 mph).
The average sea temperature is of 11.5 °C (52.5 °F). Therefore, the sea is very cold for swimming.

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December is generally a cold month. The average temperature is of 3.6 °C (39 °F), with a minimum of -1.3 °C (29.6 °F) and a maximum of 8.6 °C (47.5 °F).
On the coldest nights of the month, the temperature usually drops to around -9 °C (16 °F). However, it dropped to -14.4 °C (6.1 °F) in December 2002.
On the warmest days of the month, the temperature usually reaches around 19 °C (66.5 °F). However, it reached 25 °C (77 °F) in December 1998.
Precipitation amounts to 95 mm (3.7 in), distributed over 10 days.
The day lasts on average 9 hours and 30 minutes. December 21, the winter solstice, is the shortest day of the year in the Northern Hemisphere.
There are on average 4.5 hours of sunshine per day. So, the sun shines 49% of the time.
The average humidity is 67%.
The average wind speed is 11 kph (7 mph).
The average sea temperature is of 7 °C (45 °F). Therefore, the sea is very cold for swimming.