Mourning Warblers arrive in District of Columbia in the second week of September, peak in mid September (1.1% of checklists), and most are gone by early October.
When to look
First arrivalsSep 8-14the second week of September
Common bySep 8-14the second week of September
PeakSep 15-21mid September
Most gone byOct 1-7early October
Best: mid September. First arrivals the second week of September; most are gone by early October. Peak: on about 1.1% of District of Columbia checklists.
Jannot usually seen
Febnot usually seen
Marnot usually seen
Apruncommon
Maypeak season
Jununcommon
Julnot usually seen
Augrare
Seppeak season
Octcommon
Novuncommon
Decnot usually seen
Darker months: more checklists report it. Outlined: peak month.
Share of complete checklists reporting it, by week (4 per month). Grey bars: fewer than 10 checklists, not counted.
Frequency is the share of complete checklists in District of Columbia that listed the bird, 2016–2025. It is not a head count, and it follows where and when people go birding. How to read it.
JanFebMarAprMayJunJulAugSepOctNovDec
today
0%few checklistsno data
Each county is shaded by the share of complete checklists there that listed the bird, blended with the weeks either side. Darker is more often. It follows where people watch birds, not how many birds there are. How to read it.
Busy spots report more of everything; compare the checklist counts before you drive anywhere.
Best time of day
In District of Columbia, the Mourning Warbler is most often listed on checklists started between 5 and 7 pm (0.4% of those checklists).
Share of checklists started in each local hour that reported it. It reflects when people go birding as well as when birds are active. Grey hours have too few checklists (under 2% of the state’s, or under 200) to judge.Week-by-week table
Month
Days 1-7
8-14
15-21
22-end
January
0%
0%
0%
0%
February
0%
0%
0%
0%
March
0%
0%
0%
0%
April
0%
0%
0%
0.2%
May
0.5%
0.3%
2.0%
0.8%
June
0%
0%
0%
0%
July
0%
0%
0%
0%
August
0%
0%
0.1%
0.1%
September
0.2%
0.2%
1.5%
1.6%
October
0.1%
0.1%
0%
0.1%
November
1.3%
0%
0%
0%
December
0%
0%
0%
0%
Neighboring states
West Virginia: arrives the second week of May, 16 weeks earlier than District of Columbia
New York: arrives the second week of May, 16 weeks earlier than District of Columbia
Ohio: arrives early May, 17 weeks earlier than District of Columbia
Massachusetts: arrives mid May, 15 weeks earlier than District of Columbia
Common questions
When do Mourning Warblers arrive in District of Columbia?
Mourning Warblers arrive in District of Columbia in the second week of September, peak in mid September (1.1% of checklists), and most are gone by early October.
When do Mourning Warblers leave District of Columbia?
Most Mourning Warblers have left District of Columbia by early October, when reports fall below half their usual rate.
When is the best time to see a Mourning Warbler in District of Columbia?
The Mourning Warbler is reported most often in mid September, on about 1.1% of District of Columbia checklists.
Where in District of Columbia are Mourning Warblers seen most often?
By county, District of Columbia County have the highest peak reporting rates for the Mourning Warbler (counties with at least 200 checklists).