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With countless records smashed, this year is bringing new meaning to Miami heat

July 27, 2017 at 3:10 p.m. EDT
A boat sped out to sea against the downtown Miami skyline last week. (Alan Diaz/Associated Press)

Miami is known for its steamy weather, but this year and this month, the city has shattered an astonishing number of records for hot weather. It’s having its hottest month ever recorded, and, so far, 2017 is its warmest year.

A record challenging number of 90-degree days

Weather records for Miami are observed at Miami International Airport (MIA). The last time it showed a high temperature below 90 degrees was June 19. Thursday marked the 38th straight day with highs at or above 90.  If it hits at least 90 degrees for the next six days, it will match the record longest streak of 44 days, set in July-August 2011. Given the forecast, this is quite possible.

In July alone, Miami has hit at least 90 on 27 days — every day so far — and is closing in on the record for the month: 29 days. There’s a chance that Miami will hit at least 90 in every day of July for the first time in recorded history.

Miami’s hottest month ever

Considering the uninterrupted string of 90-degree days, it should come as no surprise that, so far, July 2017 is easily the hottest month ever recorded in Miami.

Record numbers of lows above 80 degrees

Miami’s low temperatures have also been remarkably high. So far this year, Miami has had a record 32 days with low temperatures at or above 80. The previous record, year to date, was 25 days. The average number of such days through July 27 is just eight.

The record number of lows at or above 80 for the entire year is 45 days. With another seven weeks to go until the average date of the last low temperature of at least 80, it should be easy to rack up another 14 days to break the annual record.

The month and year in perspective

To put July and 2017 in perspective, the chart on the left below presents a time series of the average temperature for July 1-26 dating to the late 1880s. On the right, a time series of the year-to-date average temperatures is shown, also dating back to the late 1800s.

July so far (on the left) is averaging 0.2 degrees warmer than the previous record (1983), while the year so far is an impressive 0.5 degrees warmer than the previous record (2015). The city has set 11 record high temperatures this year, including its hottest temperature ever observed outside of summer — 98 degrees in May. It is worth pointing out that even the coolest recent years are warmer than what the average used to be 70-plus years ago.

What makes all of these records even more impressive is that they have occurred alongside respectable rainfall totals. For the month, Miami has accumulated 11.09 inches (196 percent of average) and 40.54 inches for the year (132 percent of average). Usually, Miami experiences its hottest temperatures when it’s relatively dry. Not so this year.