D.C.’s Major October Rain Events

 

Today is the sixth consecutive day with measurable rainfall, overcast skies and below average temperatures in the Nation’s Capital.  It all began with the remnants of Hurricane Ian on September 30 and has since continued with the development of a coastal storm.  The steady northeasterly winds have kept temperatures cooler than average for almost a week now.  Record low-high temperatures occurred at National and Dulles Airports on October 4.  Here are some other significant October rain events in the D.C. Metro Area.

2021:  The first three and a half weeks of last October were very dry in the Nation’s Capital with a combined rainfall total of only 0.42”.  However, there were two significant rain events over the final week of the month.  Severe weather occurred on October 25, with a cold front following highs in the low 80s.  A coastal storm developed a few days later that brought additional heavy rain on October 29.  Consequently, October 2021 finished as a wetter than average month.

October 25:  DCA – 1.55” / IAD – 2.42” / BWI – 1.96”
October 29:  DCA – 1.15” / IAD – 1.32” / BWI – 3.01”

2013:  The D.C. Metro Area had impressive two-day rainfall totals on October 10-11 as a result of a slow moving area of low pressure.  National Airport had a two-day rainfall total of 4.54” with an October 11 record of 2.76”.  Dulles Airport set daily rainfall records on both October 10 (2.22”) and October 11 (3.38”).  The October 10 high at Dulles was only 57°.

 

2012: Hurricane Sandy was the strongest storm of the 2012 season and had significant impacts after its landfall as a “post-tropical” storm.  It caused extensive coastal flooding, set a number of rainfall and low pressure records.  In the D.C. Metro Area, record rainfall occurred over a two-day period from October 29-30.  D.C.’s three area airports had daily rainfall records on October 29, including the wettest October days on record at Dulles and BWI Airports.

 

October 29: DCA – 3.85” / IAD – 4.26” / BWI – 5.51”
October 30: DCA – 0.84” / IAD – 1.00” / BWI – 0.92”

 

2005: Following D.C.’s driest September on record in 2005 with only 0.11”, D.C. had its wettest October on record the following month with 9.41”.  The same occurred at Dulles Airport (0.15” in September 2005 to 9.22” in October 2005).  That was largely due to two consecutive days with daily rainfall records at both National and Dulles Airports.  In this case, the remnants of Tropical Storm Tammy combined with a slow moving cold front and area of low pressure to bring widespread flooding to the Mid-Atlantic Region. 

 

October 7:  DCA – 3.63” / IAD – 3.50”  

October 8:  DCA – 3.67” / IAD – 2.79”