DC’s warm November comes to a cold end

 

A late November day in the nation's capital

Despite the colder than average final two days of the month, November 2024 will still finish as the warmest on record in the nation’s capital. November will also finish as a drier than average month in the nation’s capital, the sixth such month of the year.

November had only five cooler than average days in the nation’s capital. That’s compared to 23 warmer than average November days. Three days even reached the 80s! That hasn’t happened since 1975. DC averages only one 80-degree November day roughly every five years, according to NOAA. Three record highs were also set this month.

With a monthly average temperature of 55.8° as of November 29 (that includes daily high and low temperatures), this month will finish over five degrees warmer than average. It will also set a new record for warmest November in the nation’s capital, breaking the existing record set in 2001.

Five of the last seven November’s were cooler than average in the nation’s capital, so this month should have felt especially warm by comparison. Ironically, while the recent trend has been for November to be cooler than average, eight of DC’s 15 warmest November’s have occurred just since 2000. NOAA’s current weather averages (for temperatures and precipitation) are updated every decade and the current averages reflect the 30-year period of 1991-2020. That means with the exception of 2022, those eight Novembers were factored into NOAA’s updated weather averages.

The fact that this November is drier than average has acerbated the drought conditions across the Mid-Atlantic Region. With only 1.81” of rain, well below the November average of 2.91”, this month is the 15^th with below average rainfall in the last 20 years. NOAA’s outlook for December is for near average temperatures with near to below average rainfall in the DC Metro Area.

DC’s Warmest Novembers (Source: National Weather Service)

1. 54.8° (2001)
2. 54.4° (1979, 1975)
3. 54.3° (2020, 1985)
4. 54.0° (1931)
5. 53.7° (2015)
6. 53.3° (1994)
7. 53.1° (2003, 1999)
8. 52.6° (2022, 2016)
9. 52.4° (2011)
10. 52.2° (2009, 1978)

Average – 49.9°

Good-bye to a frightening hurricane season

 

Hurricane Beryl near peak intensity (Source: NOAA)

The 2024 Atlantic hurricane season officially comes to a close on Saturday, November 30, and will finish as a busier than average season. There were a total of 18 tropical storms, of which 11 became hurricanes with 5 major hurricanes. That surpassed NOAA’s seasonal average of 14 tropical storms, 7 hurricanes with 3 major hurricanes. 

A “major” hurricane is considered a Category 3 or higher on the Saffir-Simpson Hurricane Wind Scale with sustained winds of at least 111 mph. Several hurricanes stand out this season for being both intense, destructive and deadly.

Hurricane Beryl was the earliest Category 5 hurricane on record when it reached peak intensity on July 2. It’s sustained winds were 165 mph with a minimum central air pressure of 934 millibars (mb), compared to the standard sea level air pressure of approximately 1013 mb. Fortunately, Beryl weakened below Category 5 intensity before making landfall in the Yucatan Peninsula of Mexico and made its final landfall as a minimal, Category 1 hurricane in Texas on July 8.

Hurricane Helene made landfall on September 26 as a Category 4 storm along the Florida peninsula (with 140 mph sustained winds and a minimum central air pressure of 938 mb). Although damage was substantial along the Gulf Coast, Helene’s remnants brought widespread and devastating flooding to areas well inland, particularly in the Carolinas and parts of Georgia and Tennessee. Over 200 confirmed fatalities have been reported to NOAA, making it the deadliest hurricane in the United States since Katrina in 2005.

Hurricane Milton developed in the western Gulf of Mexico in early October and quickly became the second Category 5 hurricane of the season with peak sustained winds of 180 mph and a minimum central air pressure of 897 mb. Milton’s peak winds are tied with notorious Atlantic hurricanes, Mitch (1998), Rita (2005), and Irma (2017), for third highest on record. Milton’s minimum central air pressure of 897 mb is the fifth lowest for an Atlantic hurricane behind only Wilma (2005), Gilbert (1988), “Labor Day (1935),” and Rita (2005). It also made 2024 one of only several seasons with two or more Category 5 Atlantic hurricanes.

Fortunately, by the time Milton made landfall on October 9 along Florida’s Gulf Coast, it weakened to Category 3 intensity. Nevertheless, Milton was a destructive and deadly storm that spawned a relatively high number of tornadoes across the state of Florida.

It will take some time to formulate final casualty and damage assessments for the storms that impacted the United States. However, it’s safe to say that the 2024 Atlantic hurricane season was both active and deadly and won’t soon be forgotten.

Will there be a Thanksgiving Day surprise ?

 

A dry November day in Potomac, Maryland

Some may wonder why Thanksgiving falls on a different date every year. Federal law proclaimed it a national holiday to be celebrated on the fourth Thursday of November. That means Thanksgiving 2024 will occur on November 28 when D.C.’s average high/low temperatures are 54°/38°.   

D.C.’s warmest Thanksgiving occurred on November 22, 2007 with a record high temperature of 77°. By comparison, Washingtonians had an unusually cold Thanksgiving in 2018 when the high/low was only 42°/29° on November 22. 

Longtime Washingtonians may recall that it was 35 years ago when area residents last experienced a snowy Thanksgiving. That Thanksgiving, on November 23, 1989, had a two-day snow total of 3.5”. November 1989 finished 1.6° colder than average and was followed by DC’s coldest December since 1917. In fact, 1989 remains the only time Washingtonians had both a snowy Thanksgiving and a snowy Christmas.

Accumulating November snowfall in the nation’s capital has been exceedingly rare in recent years, with only one such occurrence since 2000. Daily snowfall records were set at all three D.C. Area airports on November 15, 2018. In fact, when NOAA updated its climate averages to reflect the 30-year period of 1991-2020, replacing the 1981-2010 data set, D.C.’s November snowfall average dropped from 0.5” to 0.1”.

This month got off to a very warm start in the nation’s capital with high temperatures in the 80s on three days for the first time since 1975. While no more record heat is expected, no unusually cold weather is expected either over the rest of November. This fall’s dry weather has also continued into this month with November poised to finish with below average rainfall. That will make this November the second in three years to be both warmer and drier than average in the nation’s capital.

Washington, D.C.’s Five Coldest Thanksgiving’s by High Temperature (Source: NOAA)

1.  30°: November 27, 1930
2.  33°: November 28, 1901
     33°: November 26, 1903
3.  35°: November 23, 1989
     35°: November 28, 1996

 

Washington, D.C.’s Five Warmest Thanksgiving’s by High Temperature (Source: NOAA)

1.  77°: November 22, 2007
2.  75°: November 22, 1979
     75°: November 20, 1941
3.  75°: November 30, 1933
     73°: November 24, 1927