October’s summery start is about to change

 

An early October day in Washington, D.C.

October is the second of three months of meteorological fall and often features some of the finest weather of the year with mild days and cool, crisp nights. Average daily high/low temperatures in the nation’s capital range from 75°/58° on October 1 to 64°/46° on Halloween.  

DC’s warmest October temperature on record of 98° occurred on October 2, 2019. Eight of the last 10 Octobers have been warmer than average in Washington, D.C. Meanwhile, DC’s coolest October temperature of 26° has occurred twice, most recently on October 31, 1917. Temperatures at or below freezing in October are quite rare in the nation’s capital with none since October 20, 1992 (32°).

The nation’s capital averages 3.66” of October rainfall. However, eight of the last 10 October’s have been drier than average. Weakening tropical systems can sometimes impact the DMV (DC, Maryland and Virginia) in October with heavy rain and severe weather. Such was the case with the remnants of Hurricane Opal in 1995 and post-Tropical Storm Sandy in 2012.

Washingtonians can sometimes get an early taste of winter with light October snowfall. A trace of snow (too little to measure) does occasionally occur, with the most recent being in 2011. The earliest in the fall season the nation’s capital has experienced accumulating snowfall was on October 10, 1979, with 0.3” at National Airport.

NOAA’s Climate Prediction Center expects October 2026 to feature near average temperatures and rainfall in the nation’s capital. That would be in contrast to last October that was both cooler and drier than average.

How does DC’s September weather stand out?

 

A September day on the grounds of the National Cathedral

This month has become DC’s first wetter than average September since 2021. It will also finish more than a degree warmer than average. However, that obscures how changeable this month’s weather has been in the nation’s capital. 

Ten of the first 13 days of September were warmer than average in Washington, D.C. That includes highs in the 90s on the first four days of the month. September hadn’t had such a hot start to September since 2015. Although not quite record-setting, DC’s high of 98° on September 1 was DC’s hottest September temperature since it was 99° on September 5, 2023.

As hot as much of the first half of September was, the DMV (DC, Maryland and Virginia) saw a major shift in the weather pattern during the second half of the month. Washingtonians experienced eight consecutive cooler than average days through September 28. Measurable rainfall occurred on five of those eight days.

The nation’s capital will finish September 2026 with 4.26” of rain, compared to DC’s average of 3.93”. The wettest day was September 3 with 1.25” at National Airport. Following DC’s wetter than average August (4.27”), this month has given Washingtonians the first instance of consecutive rainier than average months since May and June of 2025.

The most memorable weather event this month was the early season Nor’easter that brought two days of measurable rainfall to the DMV on September 26-27. That also coincided with a stretch of cooler than average temperatures (eight days). Impacts in the DMV weren’t as significant as areas north and east of the nation’s capital, but were still significant. This was a long-lasting event that had far reaching impacts up and down the East Coast of the United States. Nor’easters are relatively rare events in September so it made headlines for a variety of reasons.

A closer look at Category 5 hurricanes

 

Hurricane Milton, October 2024 (Source: NOAA)

This season will become the first since 2021 that no Category 5 Atlantic hurricanes will develop. In fact, this season could become the first of the satellite era that no hurricanes of any intensity develop. That underscores just how active the 2022 – 2025 seasons were in the tropical Atlantic.

Melissa (2025): Once it reached hurricane status on October 25, Melissa underwent a period of rapid intensification. It ultimately finished tied as the third strongest Atlantic hurricane on record based on its lowest minimum air pressure of 892 millibars (mb). The lower the air pressure the stronger the storm is. Standard sea level air pressure is 1013 mb. Melissa’s peak sustained winds of 190 mph tied it for highest ever in an Atlantic hurricane. Unfortunately, it became the strongest hurricane to ever make landfall in Jamaica.

Humberto (2025): The second Category 5 of last season occurred in September, again over the open Atlantic. Humberto’s peak sustained winds were 160 mph. Its minimum central air pressure was 918 mb.

Erin (2025): The first Category 5 storm of last season developed in August and reached peak intensity over the open Atlantic. Its highest sustained winds were 160 mph and it’s lowest minimum central air pressure was 913 mb. Fortunately, Erin didn’t have any direct impacts on the United States.

Milton (2024): The second Category 5 hurricane of the season, Milton was also the strongest hurricane of 2024 with peak winds of 180 mph and a minimum central air pressure of 895 mb. Milton weakened to a still major Category 3 storm when it made landfall on the west coast of Florida on October 9. It was an exceptionally destructive storm that caused $34.3 billion in damages (2024 dollars), according to NOAA, along with 32 fatalities.

Beryl (2024): Hurricane Beryl reached peak intensity on July 2 as only the second Category 5 storm to develop in the Atlantic in July. It highest sustained winds were 165 mph and its lowest minimum central air pressure was 932 mb. Beryl was the earliest Category 5 Atlantic hurricane on record.

Lee (2023): This was the strongest hurricane of a very active Atlantic hurricane season. At peak intensity, Lee had sustained winds of 165 mph and a minimum central air pressure of 926 mb. Lee had no direct impacts on the United States.

Ian (2022): Ian was the strongest hurricane of the season and first Category 5 Atlantic hurricane since 2019. At peak intensity, Ian had sustained winds of 160 mph and a minimum central air pressure of 937 mb. Fortunately, it weakened slightly to Category 4 status before its landfall in southwestern Florida. Ian became the third costliest hurricane in US history, having caused $119.6 billion in damages according to NOAA (2024 dollars).