Global And U.S. September Were Super Warm Again, New Data Shows

Once again in September, 2024, it was hard to find 
cool places on a warming Earth. It was the second
warmest September on record, breaking a 15-
month streak of record warm months. 

 Now that we're getting climate reports again from NOAA, we can take a look at what happened in the United States and the world during September.  

To nobody's surprise, it was hot everywhere. Globally, September was the second hottest on record.  

That September was "only" the second hottest ended a 15-month streak of record warm global temperatures, according to NOAA's National Centers for Environmental Information (NCEI).     

The September reports were delayed because NCEI is located in Asheville, North Carolina. That city was ravaged by catastrophic flooding from Hurricane Helene in September. 

While the NCEI building was not damaged, the collapse of the city's infrastructure meant that NCEI could not collect data, or disseminate it.

NCEI is the largest environmental and climate data center in the world, and its servers need tons of cooling water from Asheville's municipal supply. The city's water plant was destroyed by Helene, and the city is only now restoring water service to everyone.

So things are looking  up, and we are getting data.  

GLOBAL DATA

First, let's look at the world.

As noted, September globally was the second warmest, just behind the mark set last year.  Still, 2024 now stands a 99.8 percent chance of becoming the world's warmest year on record, according to NCEI.

The familiar trend line continues. As NCEI states:

"September, 2024 marked the 50th consecutive September with global temperatures, at least nominally, above the 20th century average and the 547th consecutive month with temperatures at least nominally above the 20th century average. The past eleven Septembers (2014-2024) have been the warmest Septembers on record."

The warmest areas relative to average were most of North and South America, most of Europe. In particular, eastern Canada, eastern Europe, the Caribbean and a large chunk of Southeast Asia.

As has been the case in recent years, cool spots were few and far between. Somewhat cool areas, relative to average were in extreme western Europe, parts of Greenland and Iceland, south central Russia, Kazakhstan, parts of southern Africa and a good chunk of Antarctica. 

 UNITED STATES

Following the lead of the world, the U.S. also had its second warmest September on record.

September was the United States' second warmest
on record. Year to date is warmest on record.

Arizona, Wyoming, North Dakota, South Dakota and Minnesota had their warmest September on record.  

Here in Vermont, NCEI listed us as having the eleventh warmest September on record. It depends where you were in the state, of course. Burlington measured its fourth warmest September. 

Nobody in the United States had a cool September, though several states in the Southeast were fairly close to normal for the month. 

The twelve month period ending in September has also been the warmest on record for the United States. 

One other way to look at the relative warmth of September and the year as a whole is to inspect how many daily record highs and lows were set at thousands of weather stations across the U.S.

In September, we saw 1,734 record highs and 573 record lows. Through September 30, the nation had 23,169 record highs and 8,882 record lows.

Helping to set the stage for the drought now expanding in the United States, September was on the dry side, coming in at 40th driest out of 130 years of record. Minnesota, Iowa and Nebraska had their driest Septembers on record. Connecticut,  Delaware, Maine, Michigan, New Jersey, South Dakota and Wisconsin had one of their top ten driest Septembers.

DISASTERS

As of October 1, the number of weather disasters in the U.S. this year costing at least $1 billion is now up to 24. The only year that was worse was last year, when there were 27 such disasters through mid-October.

As you might expect, Hurricanes Helene and Milton have been added to the list of billion dollar disasters. We know each storm cost at least that much, and certainly more, but final cost estimates are not in yet.