Nashville Warblers mostly pass through Arizona: the first show up in the second week of August, they are common by mid August, peak in the second week of September (8.8% of checklists), and most are gone by late September.
When to look
First arrivalsAug 8-14the second week of August
Common byAug 15-21mid August
PeakSep 8-14the second week of September
Most gone bySep 22-30late September
Best: the second week of September. First arrivals the second week of August; most are gone by late September. Peak: on about 8.8% of Arizona checklists.
Jannot usually seen
Febnot usually seen
Marrare
Apruncommon
Mayrare
Junnot usually seen
Julnot usually seen
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 Arizona 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.
Aliso CanyonSanta Cruz County, best mid September · 28 checklists that week, 1,888 in all67%
Coronado National MemorialCochise County, best early September · 25 checklists that week, 1,157 in all55%
Patagonia Lake State ParkSanta Cruz County, best the second week of September · 64 checklists that week, 6,861 in all53%
Butterfly SpringYavapai County, best mid August · 22 checklists that week, 550 in all52%
Busy spots report more of everything; compare the checklist counts before you drive anywhere.
Best time of day
In Arizona, the Nashville Warbler is most often listed on checklists started between 5 and 7 am (2.4% 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
0.1%
0.1%
0.1%
0.1%
February
0.1%
0.1%
0.1%
0.1%
March
0.1%
0.1%
0.1%
0.5%
April
1.0%
1.9%
1.9%
1.3%
May
0.6%
0.3%
0.1%
0.1%
June
0.1%
0.1%
0.1%
0%
July
0%
0.1%
0.1%
0.1%
August
0.5%
2.1%
4.6%
7.5%
September
9.7%
9.2%
7.5%
4.6%
October
2.2%
0.7%
0.3%
0.1%
November
0.1%
0.1%
0.1%
0.1%
December
0.1%
0.1%
0.1%
0.1%
Neighboring states
New Mexico: arrives the second week of August, in the same week than Arizona
Nevada: arrives late July, 2 weeks earlier than Arizona
Utah: arrives the second week of August, in the same week than Arizona
California: arrives early April, 17 weeks earlier than Arizona
Common questions
When do Nashville Warblers arrive in Arizona?
Nashville Warblers mostly pass through Arizona: the first show up in the second week of August, they are common by mid August, peak in the second week of September (8.8% of checklists), and most are gone by late September.
When do Nashville Warblers leave Arizona?
Most Nashville Warblers have left Arizona by late September, when reports fall below half their usual rate. Stragglers are still reported until the second week of October.
When is the best time to see a Nashville Warbler in Arizona?
The Nashville Warbler is reported most often in the second week of September, on about 8.8% of Arizona checklists.
Where in Arizona are Nashville Warblers seen most often?
By county, Santa Cruz County, Yuma County, and Greenlee County have the highest peak reporting rates for the Nashville Warbler (counties with at least 200 checklists).