Common Nighthawks mostly pass through Pennsylvania: they arrive in the second week of August, peak in early September (3.9% of checklists), and most are gone by early October.
When to look
First arrivalsAug 8-14the second week of August
Common byAug 8-14the second week of August
PeakSep 1-7early September
Most gone byOct 1-7early October
Best: early September. First arrivals the second week of August; most are gone by early October. Peak: on about 3.9% of Pennsylvania checklists.
Jannot usually seen
Febnot usually seen
Marnot usually seen
Aprnot usually seen
Mayuncommon
Jununcommon
Julrare
Augpeak season
Seppeak season
Octuncommon
Novnot usually seen
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 Pennsylvania 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.
South ParkAllegheny County, best mid August · 21 checklists that week, 1,472 in all31%
Busy spots report more of everything; compare the checklist counts before you drive anywhere.
Best time of day
In Pennsylvania, the Common Nighthawk is most often listed on checklists started between 6 and 8 pm (4.5% 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%
0.1%
0%
0.1%
May
0.1%
0.6%
2.0%
1.4%
June
0.6%
0.2%
0.2%
0.2%
July
0.1%
0.2%
0.2%
0.1%
August
0.2%
0.3%
1.7%
4.8%
September
3.7%
3.0%
1.8%
1.2%
October
0.7%
0.2%
0.1%
0.1%
November
0.1%
0%
0%
0%
December
0%
0%
0%
0%
Neighboring states
Maryland: arrives the second week of August, in the same week than Pennsylvania
Delaware: arrives late July, 2 weeks earlier than Pennsylvania
New Jersey: arrives the second week of August, in the same week than Pennsylvania
Common questions
When do Common Nighthawks arrive in Pennsylvania?
Common Nighthawks mostly pass through Pennsylvania: they arrive in the second week of August, peak in early September (3.9% of checklists), and most are gone by early October.
When do Common Nighthawks leave Pennsylvania?
Most Common Nighthawks have left Pennsylvania by early October, when reports fall below half their usual rate.
When is the best time to see a Common Nighthawk in Pennsylvania?
The Common Nighthawk is reported most often in early September, on about 3.9% of Pennsylvania checklists.
Where in Pennsylvania are Common Nighthawks seen most often?
By county, Venango County, Susquehanna County, and Clarion County have the highest peak reporting rates for the Common Nighthawk (counties with at least 200 checklists).