DC's winter weather outlook

 

A chilly October morning in suburban Washington, D.C.

The nation’s capital averages 13.7” of annual snowfall, according to NOAA. Sometimes it comes in a series of smaller storms as it did during the 2014-2015 winter season. In other winters, it occurs primarily during one large storm such as during the 2015-2016 winter. Although last winter finished as DC’s coldest in more than 20 years, it also finished with below average snowfall. 

There are a lot of factors to consider when preparing a winter weather outlook, such as the status of the El Nino Southern Oscillation, “ENSO.” That refers to the presence of El Nino, La Nina or a neutral phase, or the presence of neither. NOAA expects an intensifying El Nino to play a major role in the upcoming winter season.

An El Nino winter is often warmer and wetter than average in the Mid-Atlantic Region. That’s because one of the hallmarks of an El Nino winter in the United States is a more active southern branch of the jet stream. Coastal storms sometimes develop along the southern branch of the jet stream and can become significant snow producers in the eastern United States if there’s an adequate amount of cold air.

Although many of DC’s largest winter storms have occurred during El Nino winters (2009-2010, 2002-2003, 1957-1958), having another strong El Nino this winter doesn’t mean this will be another snowy one. The 1997-1998 winter, for example, also featured a strong El Nino but the nation’s capital saw only 0.1” of snow.

During the most recent “very strong” episode of El Nino in 2015-2016, the nation’s capital had a much different winter than in 1997-1998. December 2015 was DC’s warmest on record. The first measurable snowfall of the winter didn’t occur until 0.3” fell on January 17, 2016. Less than a week later, residents of the DMV (DC, Maryland and Virginia) experienced one of the largest snowstorms on record with a total of 17.8” at National Airport on January 22-23. The rest of the 2015-2016 winter season was unremarkable and DC had a seasonal snow total of 22.2”.
 
NOAA’s outlook for the 2026-2027 winter season calls for warmer and wetter than average conditions in the DMV, largely due to the powerful El Nino that’s expected to continue into next year.

DC’s roller coaster October weather

 

NOAA's Temperature Outlook for late-October

The first half of October has featured no shortage of memorable weather in the nation’s capital. From rainy and unseasonally cool weather, to temperatures more characteristic of August than October.

DC’s signature weather event during the first half of October was the record-setting warmth that occurred on October 14. Washington, D.C. not only set a new record high for the date, but DC’s high of 90° also set a new record for latest in the calendar year it had been 90°. The previous record for latest 90-degree day was more than 100 years old when it was 90° on October 11, 1919.

All three DC-Area airports set new October 14 record highs, according to the National Weather Service.

National Airport (DCA): 90°
Dulles Airport, Sterling, Virginia (IAD): 89°
BWI Airport, Baltimore, Maryland: 88°

October 90-degree heat is exceptionally rare in the nation’s capital. That’s primarily due to the decreasing amount of daylight and decreasing sun angle. According to NOAA data over the last 30 years (1996-2025), the nation’s capital has averaged one 90-degree October day roughly every four years. Nevertheless, no 90-degree heat had been observed in Washington, D.C. before yesterday since 2019.

The first half of October has also seen near average month-to-date rainfall with 1.72” at National Airport. The wettest days so far this month were October 11-12 when the remnants of Hurricane Isaias passed through the DMV (DC, Maryland and Virginia). A two-day rainfall total of 1.06”  occurred at National Airport, 2.87” at Dulles Airport and 1.88” at BWI Airport.

Although this weekend will feature much colder weather with November-like highs in the 50s, NOAA’s Climate Prediction Center expects warmer than average temperatures to return to the DMV over the final 10 days of October.

A wrap on Hurricane Isaias

 

Hurricane Isaias, October 2026 (Source: NOAA)

Hurricane Isaias has been in the headlines for the last several days. Not only was it the first Atlantic hurricane of the season, but was also the first hurricane to make landfall in the United States in two years. The inland impacts of Isaias were far-reaching.

The 2026 Atlantic hurricane season has been notable for how quiet it’s been. Isaias set a new record for latest first hurricane when it was upgraded to hurricane status on October 8. Isaias was also the first Atlantic hurricane since Melissa last October. It was also the first hurricane in the Gulf since Rafael in November 2024.

Isaias intensified into a major hurricane Category 3 hurricane on October 9 with peak winds of 120 mph and a minimum central air pressure of 958 millibars (mb). That not only made Isaias the first hurricane of 2026, but the first major hurricane (Category 3 or greater) as well. Although Isaias made landfall in the Florida panhandle as a Category 2 storm, it caused considerable damage both at the coast and in areas well inland. Several fatalities were also reported.

The remnants of Isaias quickly became non-tropical or “post-tropical” as they tracked north and east bringing heavy rain, gusty winds and severe weather to much of the eastern United States. DC, Maryland and Virginia (DMV) experienced heavy rain and gusty winds on October 11 as the remnants of Isaias moved through. The rainfall was beneficial, however, as the nation’s capital has an ongoing year-to-date rainfall deficit of more than five inches.

It’s not without some irony either than the remnants of Isaias impacted the DMV. That’s because this is the second time Isaias has been a named storm. The first time was six years ago when Isaias made landfall in North Carolina as a Category 1 storm. Its remnants also brought heavy rain and severe weather to the DMV.

It will take some time for the final death toll and monetary cost in damages to be determined for the 2026 version of Isaias. Once that’s been completed, the World Meteorological Organization (WHO) will have to determine whether or not the name Isaias should be retired. If “Isaias” is retired, then a new I-named storm would take its place when the 2026 list of hurricane names is reused in 2032.