WhenToBird

Empidonax traillii · Tyrannidae

When Do Willow Flycatchers Arrive in Washington?

Adult Willow Flycatcher
Photo: Steven Smethurst, CC0 1.0 via iNaturalist

Willow Flycatchers reach Washington in mid May, are common by late May, peak in mid June (17% of checklists), and most are gone by the second week of August.

When to look

First arrivalsMay 15-21mid May
Common byMay 22-31late May
PeakJun 15-21mid June
Most gone byAug 8-14the second week of August

Best: mid June. First arrivals mid May; most are gone by the second week of August. Peak: on about 17% of Washington checklists.

  1. Jannot usually seen
  2. Febnot usually seen
  3. Marnot usually seen
  4. Aprnot usually seen
  5. Maycommon
  6. Junpeak season
  7. Julpeak season
  8. Augcommon
  9. Seprare
  10. Octnot usually seen
  11. Novnot usually seen
  12. Decnot usually seen

Darker months: more checklists report it. Outlined: peak month.

0%5%10%15%20%Jan 1-7: 0% of 41928 checklistsJan 8-14: 0% of 31152 checklistsJan 15-21: 0% of 31753 checklistsJan 22-31: 0% of 42530 checklistsFeb 1-7: 0% of 29739 checklistsFeb 8-14: 0% of 32746 checklistsFeb 15-21: 0% of 40328 checklistsFeb 22-28: 0% of 28432 checklistsMar 1-7: 0% of 30758 checklistsMar 8-14: 0% of 29368 checklistsMar 15-21: 0% of 32580 checklistsMar 22-31: 0% of 45614 checklistsApr 1-7: 0% of 33997 checklistsApr 8-14: 0% of 34729 checklistsApr 15-21: 0% of 38474 checklistsApr 22-30: 0% of 52185 checklistsMay 1-7: 0.1% of 44236 checklistsMay 8-14: 0.1% of 48708 checklistsMay 15-21: 2.0% of 41742 checklistsMay 22-31: 8.3% of 57082 checklistsJun 1-7: 14% of 39193 checklistsJun 8-14: 16% of 36042 checklistsJun 15-21: 18% of 34003 checklistsJun 22-30: 16% of 39711 checklistsJul 1-7: 12% of 31949 checklistsJul 8-14: 9.2% of 29086 checklistsJul 15-21: 7.8% of 28045 checklistsJul 22-31: 7.9% of 38275 checklistsAug 1-7: 7.4% of 28846 checklistsAug 8-14: 6.0% of 28036 checklistsAug 15-21: 4.6% of 27614 checklistsAug 22-31: 3.6% of 40356 checklistsSep 1-7: 2.1% of 31214 checklistsSep 8-14: 1.3% of 27795 checklistsSep 15-21: 0.6% of 29677 checklistsSep 22-30: 0.1% of 35241 checklistsOct 1-7: 0.1% of 28605 checklistsOct 8-14: 0% of 28655 checklistsOct 15-21: 0% of 24643 checklistsOct 22-31: 0% of 34874 checklistsNov 1-7: 0% of 25658 checklistsNov 8-14: 0% of 25700 checklistsNov 15-21: 0% of 24331 checklistsNov 22-30: 0% of 32784 checklistsDec 1-7: 0% of 24099 checklistsDec 8-14: 0% of 23339 checklistsDec 15-21: 0% of 27666 checklistsDec 22-31: 0% of 42130 checklistsJanFebMarAprMayJunJulAugSepOctNovDec
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 Washington 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
Second week of November

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.

Embed this map on your site

Where in Washington

Best counties

Share of checklists at the peak
  1. Cowlitz CountyBest mid June · 282 checklists that week, 15,273 in all43%
  2. Thurston CountyBest mid June · 1245 checklists that week, 68,352 in all31%
  3. Clark CountyBest mid June · 925 checklists that week, 53,250 in all30%
  4. Lewis CountyBest mid June · 359 checklists that week, 12,910 in all30%
  5. Mason CountyBest the second week of June · 521 checklists that week, 27,853 in all29%
  6. Skagit CountyBest mid June · 1344 checklists that week, 78,154 in all28%

Best spots

Share of checklists at the peak
  1. Pacific Northwest National Scenic Trail (Ennis Creek)Whatcom County, best early June · 45 checklists that week, 519 in all88%
  2. Meadowbrook SloughKing County, best the second week of June · 61 checklists that week, 865 in all87%
  3. Rutherford SloughKing County, best the second week of June · 25 checklists that week, 171 in all87%
  4. Calistoga Place ParkPierce County, best late June · 43 checklists that week, 259 in all86%

Busy spots report more of everything; compare the checklist counts before you drive anywhere.

Best time of day

In Washington, the Willow Flycatcher is most often listed on checklists started between 6 and 8 am (6.3% of those checklists).

0%5%10%12 am: too few checklists (796) to judge1 am: too few checklists (776) to judge2 am: too few checklists (709) to judge3 am: too few checklists (901) to judge4 am: too few checklists (3221) to judge5 am: too few checklists (16576) to judge6 am: 8.1% of 56744 checklists7 am: 5.6% of 133294 checklists8 am: 4.3% of 184196 checklists9 am: 3.5% of 186303 checklists10 am: 3.0% of 177063 checklists11 am: 2.4% of 154936 checklists12 pm: 1.8% of 138061 checklists1 pm: 1.6% of 127449 checklists2 pm: 1.3% of 121511 checklists3 pm: 1.2% of 107793 checklists4 pm: 1.3% of 82862 checklists5 pm: 1.8% of 57183 checklists6 pm: 2.1% of 39886 checklists7 pm: too few checklists (26969) to judge8 pm: too few checklists (12427) to judge9 pm: too few checklists (3658) to judge10 pm: too few checklists (1500) to judge11 pm: too few checklists (834) to judge12a3a6a9a12p3p6p9p
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
MonthDays 1-78-1415-2122-end
January0%0%0%0%
February0%0%0%0%
March0%0%0%0%
April0%0%0%0%
May0.1%0.1%2.0%8.3%
June14%16%18%16%
July12%9.2%7.8%7.9%
August7.4%6.0%4.6%3.6%
September2.1%1.3%0.6%0.1%
October0.1%0%0%0%
November0%0%0%0%
December0%0%0%0%

Neighboring states

  • Oregon: arrives mid May, in the same week than Washington
  • Idaho: arrives mid May, in the same week than Washington
  • Montana: arrives mid May, in the same week than Washington
  • Nevada: arrives early August, 10 weeks later than Washington

Common questions

When do Willow Flycatchers arrive in Washington?
Willow Flycatchers reach Washington in mid May, are common by late May, peak in mid June (17% of checklists), and most are gone by the second week of August.
When do Willow Flycatchers leave Washington?
Most Willow Flycatchers have left Washington by the second week of August, when reports fall below half their usual rate. Stragglers are still reported until the second week of September.
When is the best time to see a Willow Flycatcher in Washington?
The Willow Flycatcher is reported most often in mid June, on about 17% of Washington checklists.
Where in Washington are Willow Flycatchers seen most often?
By county, Cowlitz County, Thurston County, and Clark County have the highest peak reporting rates for the Willow Flycatcher (counties with at least 200 checklists).