Major October hurricanes in the Gulf of Mexico

 

Hurricane Opal making landfall, October 1995 (Source: NOAA)

Although the tropical Atlantic gradually begins to quiet down after its September peak, the Gulf of Mexico remains a favored area of development until the end of the season.  Warm ocean water (at least 80° Fahrenheit to a depth of at least 200 feet) is required for a tropical storm or hurricane to intensify under ideal atmospheric conditions. Some of the warmest water anywhere in the Atlantic Basin can be found in the Gulf of Mexico.

Smaller areas of water that features higher sea surface temperatures can sometimes influence hurricane intensity.  The Gulf of Mexico’s Loop Current is a smaller area of warmer ocean water than can influence tropical systems.  There is also something known as a “warm core ring,” which is simply an eddy or localized current of water that breaks off from the main ocean current (like the Gulf Stream or Loop Current) and can linger over an area of a few to a few hundred kilometers.  These warmer waters can provide additional fuel for an intensifying hurricane.  Here are some examples.

Zeta (2020):  Zeta reached peak intensity on October 28 as a major Category 3 hurricane as it made landfall in Louisiana.  Its highest sustained winds were 115 mph with a minimum central air pressure of 970 millibars (mb).  Although Zeta quickly weakened after its landfall, it remains noteworthy for being the latest in the season a major hurricane made landfall in the contiguous United States.  Zeta caused $5.1 billion in U.S. damages (2023 dollars), according to NOAA, along with five fatalities.

Michael (2018):  Hurricane Michael became only the fourth Category 5 hurricane to make landfall in the United States and first since Hurricane Andrew in 1992.  It also remains one of the few hurricanes that intensified up until its landfall.  Michael reached peak intensity as it made landfall along the Florida panhandle with sustained winds of 160 mph and a minimum central air pressure of 919 millibars (mb).  That part of Florida had seen several Category 3 hurricanes, but never a Category 4 or 5 storm.  Michael caused $30.2 billion in U.S. damages (2023 dollars) and claimed 16 lives during the storm, according to NOAA.

Lili (2002): Hurricane Lili reached peak intensity on October 2 while over the Gulf of Mexico as a Category 4 storm with sustained winds of 145 mph.  Lili weakened precipitously before its landfall in Louisiana as a Category 1 hurricane.  Hurricane Lili caused $1.26 billion in damages (2023 dollars) and two fatalities in the United States, according to NOAA.

Opal (1995):  Opal was one of five major hurricanes to form during the very active 1995 season.  It was also the strongest hurricane of the season as a Category 4 with peak winds of 150 mph and a minimum central air pressure of 916 millibars.  Fortunately, it weakened to Category 3 intensity before making landfall near Pensacola, Florida on October 4.  The DC Metro Area saw severe weather from the remnants of Opal on October 5.  Opal caused $9.3 billion in U.S. damages (NOAA) and 27 hurricane-related deaths according to the CDC.

Will October’s weather be frightful or delightful ?

 

The feel of fall is in the air !

September 2023 finished as a warmer and drier than average month in the nation’s capital.  DC’s average September temperature was a full degree above average largely due to the record-setting heat early in the month.  It was also slightly drier than average despite beneficial rainfall from the remnants of Tropical Storm Ophelia. 

Dulles Airport, meanwhile, had its sixth warmest September (2° above average) with its first instance of 100° September heat and finished with its 12^th wettest.  Dulles finished with 6.65” of September rainfall compared with only 3.60” at National Airport.  That helps illustrate how localized much of last month’s rain was, particularly with the remnants of Ophelia.

October is the second of three months of meteorological fall and often features some of the finest weather of the year with mild to warm days and crisp, cool nights.  Average daily high/low temperatures in the nation’s capital range from 75°/58° on October 1 to 64°/46° on Halloween.  D.C. warmest October temperature on record of 98° occurred four years ago today on October 2, 2019. 

D.C.’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 and none have occurred since October 20, 1992 (32°).  Eight of the last 10 Octobers have been warmer than average in Washington, D.C.

The nation’s capital averages 3.66” of rainfall with seven of the last 10 October’s having been drier than average.  Weakening tropical systems can sometimes impact the D.C. Metro Area 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. 

Infrequently, D.C. Area residents can get an early taste of winter with light October snowfall.  Although the nation’s capital doesn’t see enough October snowfall to produce an average amount, a trace of snow (too little to measure) does occur every once in a while, with the most recent such occurrence in 2011.  D.C. earliest accumulating snowfall occurred on October 10, 1979 with 0.3” at National Airport.

NOAA’s Climate Prediction Center expects October 2023 to be a warmer and drier than average month in the nation’s capital.  That would be in contrast to last October that finished as DC’s coolest since 2003.