By far, 2018 was Baltimore's wettest year on record. Just how wet was it?

Precipitation at Baltimore-Washington International Thurgood Marshall Airport surpassed the previous record, 62.66 inches in 2003, by Nov. 15. And in the six weeks that followed, more than 9 inches of rain fell — the same amount that falls in the final three months of an average year.

For the year, precipitation at BWI, the region’s point of record, totaled 71.82 inches.

Baltimore’s weather record book goes back to 1871.

Here’s a breakdown of the historic year:

145 rainy (and snowy days)

There was at least one-hundredth of an inch of rain at BWI on about 4 out of every 10 days. That adds up to 12 or 13 rainy days every month, on average — but in September, it rained on six out of every 10 days.

Climate data websites suggest Baltimore normally gets about 110 rainy days in a year.

Seven records within a record year

There were six daily rainfall records set, five of them during what was an unusually wet summer:

» July 17: 3.35 inches

» July 21: 4.79 inches

» July 24: 4.07 inches

» Sept. 9: 2.23 inches

» Sept. 18: 2.22 inches

» Dec. 15: 2.24 inches

And there were two monthly rainfall records.

» July: The 16.73 inches of rain was more than 5 inches above Baltimore’s previous July rainfall record, dating to 1889. It’s also the second-rainiest month ever in the region.

» November: Through Saturday, precipitation totaled 7.72 inches. The old record was 7.68 inches, set in 1952.

Three other months ranked within the top 10 wettest on record for that particular month:

» May, with 8.17 inches of rain ranked as third-wettest;

» September landed at No. 6, with 9.19 inches of rain; and,

» December finished the year as the seventh-wettest, with 6.54 inches of rain.

The region also unofficially set records for the most rain within any 14-day, 60-day, 90-day, 120-day, 180-day and 365-day period. There was more than 48 inches of precipitation in the 180 days ending Nov. 9, for example — about 6 inches more than Baltimore usually gets in a year.

There had been more than 66 inches of rain in the 365 days ending Nov. 26, just barely surpassing the 365-day period that ended Aug. 4, 1889.

The Baltimore area has already surpassed a rainfall record for July, with over 16 inches of rain falling at BWI Airport as of July 30. Where does that fall on the list of the rainiest months on record in the region?

Three flooding deaths

Floodwaters were so dangerous, they caused three deaths in two separate incidents this year.

Sgt. Eddison “Eddie” A. Hermond, 39, was swept away as he rushed to help a shop owner in Ellicott City on May 27, and his body was found days later. A devastating deluge struck the old mill town for the second time in two years.

Two people drowned in floodwaters near Abingdon on Aug. 31 — 67-year-old Daniel Samis and 34-year-old Melissa Lehew. They died as Lehew tried to rescue Samis, who was trapped in his car in floodwaters.

How Ellicott City flooded: A timeline »

On Sunday, May 27, thunderstorms pounded the Baltimore region for hours. The storm morphed Old Ellicott City into a deadly flood zone. Here’s how it happened. (Baltimore Sun video) On Sunday, May 27, thunderstorms pounded the Baltimore region for hours. The storm morphed Old Ellicott City into a deadly flood zone. Here’s how it happened. (Baltimore Sun video)

2 feet above normal

Precipitation across most of Central Maryland ended up more than 2 feet above normal, according to National Weather Service models. Many areas received more than 150 percent of normal rainfall, and in some areas, including Southwest Baltimore and areas around Frederick, it’s more than 200 percent. More than 80 inches of precipitation fell in Catonsville and Thurmont, according to the National Weather Service.

On average, about 42 inches of precipitation falls at BWI in a full year.

Two tropical systems

Some of the rainfall came from brushes with the remnants of Hurricane Florence in September and Hurricane Michael in October.

But what meteorologists found remarkable about the year of wet weather is that none of it was the product of a direct hit with a tropical system, unlike many of Baltimore’s other wettest years on record.

Much of the rain was instead the result of an unusual and persistently wet weather pattern that dominated for much of the summer.

On pace for its wettest year on record, Baltimore has already topped 50 inches of rain in 2018. That translates to almost 80 billion gallons over the city's 92 square miles. To put it in perspective, here are a few comparisons.

1 inch of rainfall — in 10 minutes

It’s impossible to know when and where the most intense burst of rainfall fell — but if Ellicott City’s flooding is any indication, there were moments of extreme precipitation around the state.

As torrential downpours hovered over the historic mill town May 27, 0.96 inches of rain fell in a 10-minute span, from 4:11 p.m. to 4:21 p.m. Almost 2 inches fell within a 30-minute stretch, and nearly 3 inches within an hour. Ellicott City saw 6.56 inches of rain in a three-hour span that afternoon.

Photos of weather in Maryland in 2018.

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