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Flash Flood Watches in Southeast and Tennessee Valley; Critical Fire Weather in California; Severe Weather in Upper Midwest

Flash flood watches are in effect today in parts of the Southeast and Tennessee Valley from organized areas of heavy to excessive rainfall. Meanwhile, critical fire weather conditions are likely across northern California with offshore winds and dry conditions. Finally, a strong cold front will produce severe thunderstorms across the Upper to Mid Mississippi Valley. Read More >

Floods and Record Rainfall of 2018

(Page last updated February 11, 2019. Information is still being added to this page.)

All information presented here is preliminary and subject to future correction.
Click or tap on each header below to view additional information.

 

2018 was a memorable year for the Mid-Atlantic region, with some of the most frequent and persistent flooding observed in many years. While the severity of the flooding was not record breaking, the persistent nature of the rain kept conditions primed for flooding for about 75% of the year.

This page looks back at the significant and record-breaking rainfall from 2018, as well as the numerous flood events which occurred. Not all flood events are represented here; only the most significant are included.

Below is a map showing estimated rainfall (and melted snowfall) from the entire year. Click on it to make it larger:

PRELIMINARY RAINFALL RECORDS (with ending date):
Last updated after end of day 1/27/2019
2018 totals that did not set records are shown in purple. 2018 totals that did set records are in RED with the old record indicated. All information is preliminary and subject to correction.

 

BWI - Baltimore, MD

DCA - Washington, DC/VA

IAD - Dulles, VA

1 day

7.62 (8/23/1933)
4.79 (7/21/2018) 10th

6.39 (8/23/1933)
4.00 (7/21/2018) 24th

10.67 (6/21/1972)
5.02 (7/21/2018) 5th

2 days

8.50 (8/13/1955)
5.49 (7/24/2018) 21st

9.41 (6/26/2006)
5.35 (7/22/2018) 21st

12.63 (6/22/1972)
5.10 (7/22/2018) 14th

3 days

10.98 (8/23/1933)
6.71 (7/23/2018) 8th

10.34 (6/27/2006)
5.41 (7/23/2018) 44th

13.18 (6/22/1972)
5.57 (7/23/2018) 19th

7 days

13.87 (8/18/1955)
12.14 (7/27/2018) 3rd

11.37 (6/28/2006)
8.20 (7/23/2018) 33rd

14.13 (6/23/1972)
7.76 (7/27/2018) 23rd

14 days

16.37 (7/28/2018)
old 15.93 (8/23/1955)

14.09 (7/2/2006)
9.70 (7/30/2018) 77th

17.30 (7/3/1972)
10.66 (8/3/2018) 24th

30 days

18.90 (9/11/2011)
18.56 (8/14/2018) 2nd

17.45 (10/2/1934)
2018 not in top 100

18.78 (7/3/1972)
12.30 (8/1/2018) 60th

60 days

24.19 (9/13/2018)
old 23.91 (10/1/2011)

23.37 (9/22/1934)
20.69 (9/14/2018) 35th

22.95 (7/1/1972)
20.33 (9/13/2018) 22nd

90 days

31.21 (8/7/2018)
old 27.01 (10/31/2011)

28.85 (8/2/1886)
26.19 (10/14/2018) 23rd

27.71 (7/5/1972)
25.98 (10/14/2018) 17th

120 days

36.51 (9/9/2018)
old 32.78 (8/3/1889)

34.45 (9/9/2018)
old 34.10 (7/26/1886)

33.67 (9/9/2018)
old 30.31 (7/9/1972)

180 days

48.39 (11/9/2018)
old 41.72 (8/14/1889)

44.66 (11/7/2018)
old 42.28 (8/1/1886)

44.15 (11/8/2018)
old 40.58 (11/5/2003)

365 days

** these records are still being set as of 1/27/19

73.81 (1/27/2019)**
old 65.95 (8/4/1889)

70.60 (7/26/1886)
68.60 (1/27/2019) 9th **

68.75 (1/27/2019)**
old 66.57 (12/19/2003)

Calendar Year

71.82 (2018)
old 62.66 (2003)

66.28 (2018)
old 61.33 (1889)

66.74 (2018)
old 65.67 (2003)

Wettest Calendar
Months

16.73 (July 2018)
old 11.03 (1889)


8.14 (Nov 2018)
old 7.68 (1952)

7.57 (Nov 2018)
old 7.18 (1877)

11.21 (July 2018)
old 8.80 (2017)

Wettest Two-month or Seasonal periods

(Note: "Summer" =
June-July-August

"Fall" = Sep-Oct-Nov)

20.02 (Fall 2018)
old 19.56 (Fall 2006)


25.38 (Summer 1955)
25.34 (Summer 2018) 2nd


21.50 (Jun-Jul 2018)
old 17.20 (Jun-Jul 1889)


20.57 (Jul-Aug 2018)
old 18.65 (Jul-Aug 1955)


14.68 (Nov-Dec 2018)
old 13.00 (Nov-Dec 2009)

21.78 (Fall 1934)
20.36 (Fall 2018) 2nd

13.39(Nov-Dec 2018)
old 11.22 (Nov-Dec 2009)

22.61 (Summer 2018)
old 21.81 (Summer 1972)


18.88 (Fall 1979)
17.72 (Fall 2018) 2nd


18.44 (Jul-Aug 2018)
old 13.17(Jul-Aug 1984)


13.44 (Nov-Dec 2018)
old 13.15 (Nov-Dec 1972)

 

Other statistics

 

BWI

DCA

IAD

Raindays

169 (1889)
145 (2018) 7th

159 (1889)
131 (2018) not signif.

155 (2003)
142 (2018) 4th

Days ½” or more

48 (2018)
old 42 (1948)

44 (1937)
43 (2018) 2nd

48 (2018)
old 42 (2003)

Days 1” or more

20 (2018)
ties record from 1979

24 (2018)
old 21 (1878)

23 (1996)
19 (2018) 3rd

Days 2” or more

6 (2018)
ties record: 1952/1889

6 (1886 & 1878)
5 (2018) 3rd

5 (1993 & 1963)
4 (2018) 3rd

Consecutive Days

 

>1/4 inch:
7 days ending 5/19/2018
Old 5 days ending 9/9/2011

>1/4 inch:
7 days ending 5/19/2018
Old 5 days ending 9/9/2011

 

Specifically at BWI:

The wettest June, July, September, October, November, and December have all been since 2005.

The July total of 16.73 is the second wettest calendar month on record, behind 18.35 in August 1955.

Preliminary Precipitation Totals for 2018

Location State County Total Departure
MECHANICSVILLE 5 NE MD Saint Mary's 80.78 +35.03
MILLERS 4 NE MD Carroll 79.35 +34.71
FREE UNION VA Albemarle 78.62 +33.14
EMMITSBURG 2 SE MD Frederick 77.16 +33.45
FROSTBURG 2 MD Allegany 74.58 +30.17
CHARLOTTESVILLE 2W VA Albemarle 72.14 +24.46
BAYARD WV Grant 71.86 +21.66
BWI AIRPORT MD Anne Arundel 71.82 +29.94
MOUNT WEATHER 3 VA Clarke 71.08          N/A
CONOWINGO DAM MD Harford 70.25 +22.80
MARYLAND SCIENCE CENTER MD Baltimore 68.76 +27.87
NATIONAL ARBORETUM DC DC District of Columbia 68.01 +24.48
WILLIAMSPORT MD Washington 67.76 +27.17
KEYSER 2 SSW WV Mineral 67.22 +27.35
HAGERSTOWN 1 E MD Washington 67.10           N/A
CUMBERLAND 2 MD Allegany 67.06 +29.70
WASHINGTON DULLES INTL AP VA Loudoun 66.74 +25.20
PURCELLVILLE VA Loudoun 66.55           N/A
WASHINGTON REAGAN NATIONAL AIRPORT VA Arlington 66.28 +26.54
BELTSVILLE MD Prince George's 65.90 +24.06
WINCHESTER VA Frederick 65.86 +27.53
OXON HILL MD Prince George's 65.26 +20.72
DAMASCUS 3 SSW MD Montgomery 65.01 +18.65
WFO STERLING VA Loudoun 64.66 +21.73
PATUXENT RIVER NAS MD Saint Mary's 63.66 +17.01
CHARLOTTESVILLE ALBEMARLE AP VA Albemarle 62.59 +19.88
STAUNTON WATER TREATMENT PLANT VA Augusta 58.85 +19.75
MILL GAP VA Highland 56.31 +12.03

 

Autumn of 2017 and much of the winter of 2018 were quite dry in the mid-Atlantic region.  Starting in April, greater and more routine rainfall began to occur, prompting several significant floods. We have done reviews of some of the events.  Select the date (where available) for more information:

  • April 16th - Eastern West Virginia
  • May 15th & 16th - Frederick, Maryland
  • May 22nd - Fulks Run, Virginia
  • May 27th - Ellicott City & Catonsville, Maryland
  • May 30th & 31st - Charlottesville & Greene/Madison, Virginia
  • June 3rd - Berkeley Springs, West Virginia
  • June 22nd - Rappahannock River Basin, Virginia
  • July 21st - DC Metropolitan Area
  • July 24th - Northern Baltimore County
  • August 4th - North Central Maryland
  • August 13th - Baltimore Metropolitan Area
  • August 31st & September 1st - Harford County, Maryland & Northern Maryland
  • September 9th - Remnants of "Gordon"
  • September 17th & 18th - Remnants of "Florence"
  • November 24th & 25th - Thanksgiving weekend coastal low
  • December 15th & 16th - Coastal low with widespread flooding

Below are the monthly estimated rainfall totals for each month, starting in April.  (Currently only April through June are available due to webpage issues. We intend to add the rest of the months soon.) Click on each image to make it larger: