Philadelphia Vireos mostly pass through Kentucky: they arrive in early September, peak in late September (4.8% of checklists), and most are gone by the second week of October.
When to look
First arrivalsSep 1-7early September
Common bySep 1-7early September
PeakSep 22-30late September
Most gone byOct 8-14the second week of October
Best: late September. First arrivals early September; most are gone by the second week of October. Peak: on about 4.8% of Kentucky checklists.
Jannot usually seen
Febnot usually seen
Marnot usually seen
Aprrare
Maycommon
Junnot usually seen
Julnot usually seen
Augrare
Seppeak season
Octcommon
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 Kentucky 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.
Willow LakeJefferson County, best late September · 71 checklists that week, 1,890 in all31%
Cherokee ParkJefferson County, best late September · 23 checklists that week, 1,395 in all25%
Busy spots report more of everything; compare the checklist counts before you drive anywhere.
Best time of day
In Kentucky, the Philadelphia Vireo is most often listed on checklists started between 7 and 9 am (1.2% 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%
0.4%
May
1.7%
2.9%
2.5%
0.4%
June
0%
0%
0%
0%
July
0%
0%
0%
0%
August
0%
0%
0.1%
0.1%
September
1.9%
3.4%
4.9%
5.8%
October
3.5%
1.2%
0.3%
0.1%
November
0%
0%
0%
0%
December
0%
0%
0%
0%
Neighboring states
Tennessee: arrives the second week of September, 1 week later than Kentucky
Indiana: arrives late August, 1 week earlier than Kentucky
Ohio: arrives late August, 1 week earlier than Kentucky
Illinois: arrives late August, 1 week earlier than Kentucky
Common questions
When do Philadelphia Vireos arrive in Kentucky?
Philadelphia Vireos mostly pass through Kentucky: they arrive in early September, peak in late September (4.8% of checklists), and most are gone by the second week of October.
When do Philadelphia Vireos leave Kentucky?
Most Philadelphia Vireos have left Kentucky by the second week of October, when reports fall below half their usual rate.
When is the best time to see a Philadelphia Vireo in Kentucky?
The Philadelphia Vireo is reported most often in late September, on about 4.8% of Kentucky checklists.
Where in Kentucky are Philadelphia Vireos seen most often?
By county, Metcalfe County, Muhlenberg County, and McCreary County have the highest peak reporting rates for the Philadelphia Vireo (counties with at least 200 checklists).