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What Is the Rainiest City in the US? Top 11 Wettest Cities

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Two people fishing off a dock on a rainy day in Seattle

We’ve all been there at some point: cooped up inside on a rainy day, playing the same old board game for the twelfth time, wondering when the storm will break, and convinced we managed to move to or visit the rainiest city in the US. But where does it rain the most in the US?

Other than your hometown, your first guess might be Seattle, Washington. Famous for its dreary winter rains, Seattle gets plenty of precipitation and more than its fair share of gray days, but it doesn’t even make the top ten!

Read on to find out which cities (with a population above 25,000) are the wettest in the US.

Cities are ranked here by the number of days with measurable precipitation (0.01 inches or more). This precipitation can fall as rain, snow, sleet, freezing rain, or a mixture. For this list, if you melt down whatever falls into liquid form and end up with at least 0.01 inches of liquid, it counts as a “rainy” day. In the event of a tie, cities are ranked by the highest annual average total precipitation, also including the liquid water equivalent of frozen precipitation.

What Is the Rainiest City in the United States?

Let’s take a look at the rainiest places in the United States, according to the average number of days with measurable precipitation using data from NOAA’s National Centers for Environmental Information (NCEI).

1. Hilo, Hawaii

Coconut Island in Hilo Hawaii
  • Average Annual Rainy Days: 276
  • Average Annual Precipitation: 156.79 inches
  • Average Wettest Month: July and August
  • Average Driest Month: January and February

Hilo, Hawaii, takes the top spot for the rainiest city in the US, with an average of 276 days of rain per year. That means over three-quarters of all days in Hilo produce at least some rain!

Why does this happen? There are two key reasons. First, Hilo is located on the windward side of the Big Island of Hawaii, which means that it is directly in the path of moist trade winds that blow in from the Pacific Ocean. These trade winds pick up moisture as they pass over the ocean and release it as rain when they encounter the mountains on the island.

Second, the city is situated in a valley surrounded by mountains, which help squeeze the moisture out of the passing trade winds, especially when the mountains act as a catalyst to promote the growth of afternoon thunderstorms.

The high rainfall in Hilo has both positive and negative impacts. On the one hand, it provides the city with a lush, green landscape and abundant water for agriculture and other purposes. However, frequent rain can also cause flooding and landslides, which can be dangerous for residents.

Hilo’s wettest season is the summer, with 27 days of rain on average during July and August, while the winter is driest, with “only” 17 days of rain during January and February.

2. Juneau, Alaska

Juneau, Alaska
  • Average Annual Rainy Days: 224
  • Average Annual Precipitation: 62.27 inches
  • Average Wettest Month: October
  • Average Driest Month: June

Juneau takes the number two spot with 224 days of rain on average each year. Its rain comes primarily from strong Pacific storms that draw moisture north from Hawaii towards Alaska, which clashes with cold air from the North Pole. These air mass clashes can produce violent storms responsible for days of rain. Sometimes enough cold air is present to produce snow, which can accumulate significantly: Juneau averages 93.6 inches of snow yearly!

Additionally, even when no powerful storms are nearby, rain or snow can occur in Juneau due to its proximity to the Pacific Ocean and high coastal mountain ranges. Much like Hawaii, when moisture-laden air blowing across the Pacific smashes into tall mountains, it results in heavy precipitation.

Juneau’s wettest season is autumn, with October bringing 23 days of rain on average, while summers are usually drier, with June only producing 16 days of precipitation on average.

3. San Juan, Puerto Rico

San Juan, Puerto Rico
  • Average Annual Rainy Days: 202
  • Average Annual Precipitation: 56.35 inches
  • Average Wettest Month: December
  • Average Driest Month: March and April

Much like Hilo, San Juan, Puerto Rico, earns a spot in the top eleven based on the interaction between tropical moisture, trade winds, and tall mountains. Where Hawaii gets its moisture from trade winds blowing across the Pacific, San Juan and the rest of Puerto Rico get moisture from the same trade winds as they blow across the Atlantic. When these moisture-laden winds encounter the tall mountains in Puerto Rico, the moisture they carry is squeezed out in the form of torrential downpours.

San Juan’s rainiest month is December, when 20 days, on average, feature precipitation of some measurable amount. March and April comprise the “dry” season, with only 13 days of rain, on average, each month.

4. Syracuse, New York

Syracuse, New York
  • Average Annual Rainy Days: 172
  • Average Annual Precipitation: 38.47 inches
  • Average Wettest Month: December and January
  • Average Driest Month: August

Moving out of the tropics and the exceptionally rainy coastal Alaska, even the wettest city in the lower 48 doesn’t quite manage to log precipitation on more than half of the days of the year. Still, Syracuse’s average annual rainy (or snowy) day count of 172 days is impressive! Especially when you consider that the city is over 1,000 miles from tropical oceans and is even farther from serious mountain ranges.

So how can Syracuse beat Miami and Seattle, among others, for the fourth spot? The answer lies about 20 miles northwest of the city: Lake Ontario.

During the winter, cold air from Canada moves across the still-warm lakes to produce bands of lake-effect rain and snow. How does this happen? Warm air is less dense than cold air and will rise if located beneath colder air. When cold air masses come south out of Canada in the winter, a small layer of warm air adjacent to the Great Lakes is trapped beneath a much colder blanket of air coming in from the north. This warm air, which also happens to be rich with moisture due to evaporation from the lakes, then rises (remember it is less dense than the surrounding cold air). As it rises, the lake air cools, which means it can hold less moisture, and any excess must fall out as rain or snow.

Lake-effect rain and/or snow can last for days, which is why Syracuse, and most of the top eleven list, are located near the southern or eastern shores of the Great Lakes. Syracuse also has the honor of being the snowiest major city in the United States, with an average annual snowfall total of 114.3 inches. During the summer, the lake doesn’t affect the city’s weather very much, and partly as a result, August is its driest month.

5. Buffalo, New York

What Is the Rainiest City in the US? Top 11 Wettest Cities 1
  • Average Annual Rainy Days: 167
  • Average Annual Precipitation: 40.48 inches
  • Average Wettest Month: January
  • Average Driest Month: July and August

Buffalo, New York, earns its spot in the top eleven the same way Syracuse does: months and months of lake-effect snow and rain during the winter. January is Buffalo’s wettest month, though most of its precipitation during this time falls as snow. In an average year, 92.0 inches of snow accumulates in Buffalo. Sometimes the city can approach that number in a single storm! During the summer, nearby Lake Erie inhibits rainfall when its cooler waters suppress the instability needed for thunderstorm growth. Therefore, July and August are much drier in Buffalo.

6. Olympia, Washington

Washington State Capitol Building in Olympia, Washington
  • Average Annual Rainy Days: 163
  • Average Annual Precipitation: 50.00 inches
  • Average Wettest Month: December and January
  • Average Driest Month: July and August

Just down from Puget Sound and the notoriously soggy Seattle, Olympia earns a spot in the top eleven thanks to moisture-laden Pacific storms crashing into the Cascade mountains located just east of the city.

Why does Olympia come in at a respectable number six, well above nearby Seattle? Seattle is also west of the Cascades, it’s true, but it’s east of another mountain range: the Olympic Mountains on the Olympic Peninsula that forms Washington’s northwesternmost reaches. When air coming in from the Pacific Ocean hits these mountains, moisture gets wrung out, just like in Hawaii and Alaska, leaving less available moisture for rain and snow in Seattle. Olympia is just far enough south not to suffer the same disruptions during most storms that feature westerly or southwesterly winds.

Winter is Olympia’s wettest period, with December and January each recording 20 wet days on average. Summer is very dry in Olympia, with only 5 days of rain on average during July and August.

7. Erie, Pennsylvania

Erie, Pennsylvania
  • Average Annual Rainy Days: 162
  • Average Annual Precipitation: 42.16 inches
  • Average Wettest Month: December and January
  • Average Driest Month: July, August, and September

Located on the southern shore of Lake Erie, Erie, Pennsylvania, also experiences regular lake-effect storms during the winter months. In contrast, summers (especially August) are quite dry.

With its 162 days of precipitation, on average, tied with Binghamton and Rochester across the border in New York, Erie claims the number seven spot with an annual average rainfall tally of 42.16 inches leveraging its position slightly farther east along Lake Erie than Rochester is along Lake Ontario. Cold air usually enters the Great Lakes region from the west or northwest, which means that cities east of the lakes are favored for lake-effect precipitation.

8. Binghamton, New York

Binghamton, New York
  • Average Annual Rainy Days: 162
  • Average Annual Precipitation: 39.30 inches
  • Average Wettest Month: December
  • Average Driest Month: July, August, and September

It’s the same old story for Binghamton, New York, also located downwind of the Great Lakes in the central part of New York state. Unlike Syracuse, Buffalo, and Erie, Binghamton isn’t directly adjacent to one of the Great Lakes, but lake-effect storms can send light rain and snow dozens or sometimes even hundreds of miles downwind.

This means that Binghamton rarely gets the epic blizzards observed in Buffalo or even Syracuse, and its 84.7 inches of average snowfall is lower than any of the other upstate New York cities on this list. Even so, Binghamton logs just enough days with light precipitation to tie Erie and Rochester with an average of 162 days of precipitation each year.

In the summer, though, Binghamton’s greater distance from the lakes becomes an asset as thunderstorms have an easier time developing near and dumping rain on the city. Summer thunderstorms are most common earlier in the season, and by July, the dry season begins with only ten days of rain, on average occurring in July, August, and September. Binghamton’s average annual rainfall total of 39.30 inches pushes Rochester down to spot number nine.

9. Rochester, New York

Pont De Rennes bridge in Rochester, New York
  • Average Annual Rainy Days: 162
  • Average Annual Precipitation: 34.27 inches
  • Average Wettest Month: January
  • Average Driest Month: July and August

There isn’t much more to say about Rochester, New York, that hasn’t already been said above. It’s just south of Lake Ontario but far enough west along the lake to miss out on the prolific blizzards that blanket Buffalo and Syracuse.

Day after day of lighter snow earns it a tie with Erie and Binghamton in terms of the number of days per year with at least some precipitation. That said, the suboptimal lake alignment and close proximity to cool, thunderstorm-killing air in the summer put it at the bottom of the heap in terms of average annual rainfall, at least among those cities with 162 days of precipitation on average. Still, Rochester manages to stack up 89.3 inches of snow each year, a very respectable showing!

10. Youngstown, Ohio

Youngstown, Ohio
  • Average Annual Rainy Days: 159
  • Average Annual Precipitation: 38.91 inches
  • Average Wettest Month: December and January
  • Average Driest Month: August and September

Youngstown, Ohio, takes the number ten spot with 159 days of precipitation each year. Located 55 miles southeast of Lake Erie, Youngstown can benefit from lake-effect precipitation, though to a much lesser extent than cities closer to the lakes, such as Buffalo, Syracuse, and Rochester. Youngstown’s marginal proximity to Lake Erie is enough to earn it 57.5 inches of snowfall each year.

Youngstown also has the benefit of sitting near the western edge of the Appalachian mountains, meaning that when moisture-laden air arrives from the Gulf of Mexico or the Great Lakes, it is forced to rise up the gently-sloping foothills. While nowhere near as prolific as the mountain-induced assist that Juneau or Olympia might get, the combination of just enough lake-effect exposure and just enough mountain boost, combined with plenty of summer thunderstorms, puts Youngstown on the board at number ten.

Late summer and early fall are the driest times in Youngstown after the peak thunderstorm season and before the peak lake-effect season. Lake effect beats out the summertime thunderstorms for the wettest season, which is December into January.

11. Akron, Ohio

Akron, Ohio
  • Average Annual Rainy Days: 156
  • Average Annual Precipitation: 39.62 inches
  • Average Wettest Month: January
  • Average Driest Month: August and September

Akron is located in northeastern Ohio, just south of Cleveland, and benefits from lake effect much like many other cities on this list. Because lake effect plays a big part in Akron’s propensity for precipitation, January is the wettest month when plenty of cold air is moving down from Canada, while Lake Erie hasn’t completely frozen over yet. August and September are the driest months of the year after peak summertime thunderstorm season and before lake effect begins in earnest.

Akron has the same number of rainy (and/or snowy) days as nearby Cleveland. Still, it barely takes the number eleven spot because of its slightly higher average annual rainfall total. Better support for summertime thunderstorms farther from Lake Erie is probably responsible for this difference. On the flip side, because it’s farther from Lake Erie, Akron doesn’t get quite as much snow, with “only” 47.6 inches stacking up in an average year. That’s still better than the US average but almost exactly 10 inches less than Cleveland.

Honorable Mention: Seattle, Washington

Seattle, Washington

Seattle, the famously rainy city, barely missed inclusion in the top-eleven list. Like Akron and Cleveland in Ohio, Seattle also logs 156 days with rain (or snow) on average each year, but it falls just short in our tie-breaker metric of total average annual precipitation at 37.49 inches.

Rainiest Cities Based on Average Annual Precipitation Total

Miami, Florida
Miami, Florida, experiences 61.90 inches of precipitation on average each year.

Why aren’t any cities from the humid, often-soaked southeastern US on this list? With its tropical storms and hurricanes, Miami seems pretty rainy, right? This list rewards consistency over intensity by ranking cities based on the number of rainy days per year. Even a few stray snowflakes emerging from an otherwise dry cloud on the edge of a lake-effect band helps the Great Lakes sweep most of the top eleven listed above. While it often takes a full-on deluge for Miami, New Orleans, or Houston to tally a rainy day.

So, what do the standings look like if we rank each United States City by the total amount of rain (and liquid water equivalent of snowfall) that falls from the sky each year? Read on to find out! Like the top-eleven list above, we are using data from the National Centers for Environmental Information (NCEI) to compute these rankings, and we’re only including cities within the United States with a population greater than 25,000.

  1. Hilo, Hawaii: 156.79 inches
  2. Mobile, Alabama: 65.28 inches
  3. New Orleans, Louisiana: 62.45 inches
  4. West Palm Beach, Florida: 62.33 inches
  5. Juneau, Alaska: 62.27 inches
  6. Miami, Florida: 61.90 inches
  7. Pensacola, Florida: 61.20 inches
  8. Baton Rouge, Louisiana: 60.65 inches
  9. Port Arthur, Texas: 60.47 inches
  10. Tallahassee, Florida: 59.23 inches
  11. Wilmington, North Carolina: 57.61 inches

Final Thoughts

Which cities in the United States you consider the rainiest depends somewhat on how you view a “rainy” day. Is your definition of a rainy city one where it rains often? If so, Hawaii and coastal Alaska take the top spots as the rainiest places in the US, but the rest of the list is dominated by the Great Lakes, thanks mostly to lake-effect storms. If your definition of a rainy city is one where the rain falls in prodigious quantities, the southeastern US is generally your bullseye.

That said, Hilo, Hawaii, tops the charts no matter how you measure it, which means we can unambiguously give it the title of the wettest city in the United States.

This list is compiled using data from the National Centers for Environmental Information’s Comparative Climatic Dataset. This dataset uses information spanning from the late 1940s or early 1950s (depending on the station) until 2020, ensuring a long period of reliable data to make comparisons.


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