Notable June Tropical Systems

 

Rainfall from T.S. Allison, June 2001 (Source: NOAA)

Hurricane season in the Atlantic Ocean Basin runs from June 1 - November 30.  June and November are typically the quietest months of the season when atmospheric and environmental conditions are the least favorable for development.  That’s not to say there haven’t been several high impact tropical storms and hurricanes during the month of June.

Chris (2012):  The 2012 Atlantic hurricane season got off to a fast start with four named storms by the end of June.  Chris became the first hurricane of the season and was a Category 1 at peak intensity with 85 mph sustained winds.  Chris meandered around the northern Atlantic and had no direct impacts on land while a named storm.  It was noteworthy for being the farthest north any June hurricane has developed in the Atlantic.  According to NOAA, Hurricane Chris “developed from a baroclinic low that formed along a cold front near Bermuda.”  That means this storm relied on a strong air temperature gradient to help it develop since sea surface temperatures were only in the low 70s, well below the 80° threshold a tropical system normally requires to develop.

Allison (2001):  Tropical Storm Allison had the impressive distinction of being the first storm to have its name retired by the World Meteorological Organization without reaching hurricane intensity.  Tropical storm and hurricane names are retired for being damaging and/or deadly (a la Katrina, Andrew or Michael).  What made Allison unique wasn’t its intensity, but its longevity.  After making landfall in Texas, its remnants lingered for days and caused devastating flooding.  Not until Hurricane Harvey in August 2017 did Texas residents see comparable flooding.  According to the National Hurricane Center, Allison caused an estimated $9 billion in damage (unadjusted for inflation) and remains the only tropical storm on the list of costliest hurricanes on record in the United States.

Bonnie (1986): Hurricane Bonnie was a rare June hurricane that developed in the Gulf of Mexico and became a Category 1 storm.  It made landfall near the Texas/Louisiana border and brought flooding rainfall to much of the U.S. Gulf Coast region.  At peak intensity, Bonnie remained just below hurricane strength and was a prolific rain producer.  This was the last hurricane to make landfall in the United States during the month of June.

Agnes (1972):  Agnes became a minimal hurricane over the eastern Gulf of Mexico on June 18, but isn’t remembered for that.  As a weaker tropical storm, Agnes menaced much of the Mid-Atlantic and northeastern United States where its remnants caused widespread flooding.  Multiple June rainfall records were set from Virginia to New York, including DC’s wettest June day overall (6.11” on June 21, 1972).  Agnes subsequently had its name retired.  Agnes and the flooding its remnants produced led to over 100 deaths, according to the National Weather Service.