WhenToBird

Petrochelidon pyrrhonota · Hirundinidae

When Do Cliff Swallows Arrive in Washington?

Adult Cliff Swallow
Photo: Dean Hester, CC BY 4.0 via iNaturalist

Cliff Swallows reach Washington in early April, are common by mid April, peak in early June (10% of checklists), and most are gone by early August.

When to look

First arrivalsApr 1-7early April
Common byApr 15-21mid April
PeakJun 1-7early June
Most gone byAug 1-7early August

Best: early June. First arrivals early April; most are gone by early August. Peak: on about 10% of Washington checklists.

  1. Jannot usually seen
  2. Febnot usually seen
  3. Marrare
  4. Aprcommon
  5. Maypeak season
  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%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: 0.1% of 30758 checklistsMar 8-14: 0.1% of 29368 checklistsMar 15-21: 0.1% of 32580 checklistsMar 22-31: 0.5% of 45614 checklistsApr 1-7: 1.5% of 33997 checklistsApr 8-14: 3.3% of 34729 checklistsApr 15-21: 4.6% of 38474 checklistsApr 22-30: 6.5% of 52185 checklistsMay 1-7: 8.1% of 44236 checklistsMay 8-14: 8.5% of 48708 checklistsMay 15-21: 10% of 41742 checklistsMay 22-31: 10% of 57082 checklistsJun 1-7: 10% of 39193 checklistsJun 8-14: 10% of 36042 checklistsJun 15-21: 9.5% of 34003 checklistsJun 22-30: 9.2% of 39711 checklistsJul 1-7: 8.7% of 31949 checklistsJul 8-14: 8.5% of 29086 checklistsJul 15-21: 7.2% of 28045 checklistsJul 22-31: 6.2% of 38275 checklistsAug 1-7: 5.0% of 28846 checklistsAug 8-14: 3.9% of 28036 checklistsAug 15-21: 3.2% of 27614 checklistsAug 22-31: 2.1% of 40356 checklistsSep 1-7: 0.9% of 31214 checklistsSep 8-14: 0.3% of 27795 checklistsSep 15-21: 0.2% of 29677 checklistsSep 22-30: 0.1% of 35241 checklistsOct 1-7: 0.1% of 28605 checklistsOct 8-14: 0.1% of 28655 checklistsOct 15-21: 0% of 24643 checklistsOct 22-31: 0% of 34874 checklistsNov 1-7: 0.1% of 25658 checklistsNov 8-14: 0.1% of 25700 checklistsNov 15-21: 0.1% of 24331 checklistsNov 22-30: 0.1% of 32784 checklistsDec 1-7: 0.1% of 24099 checklistsDec 8-14: 0.1% 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.

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Where in Washington

Best counties

Share of checklists at the peak
  1. Adams CountyBest late May · 223 checklists that week, 4,574 in all47%
  2. Benton CountyBest mid June · 365 checklists that week, 23,565 in all41%
  3. Franklin CountyBest mid June · 115 checklists that week, 7,970 in all40%
  4. Garfield CountyBest the second week of May · 22 checklists that week, 1,130 in all31%
  5. Lincoln CountyBest mid June · 149 checklists that week, 6,135 in all30%
  6. Walla Walla CountyBest mid May · 1008 checklists that week, 35,829 in all28%

Best spots

Share of checklists at the peak
  1. Slaughter Pen BayWhitman County, best the second week of June · 23 checklists that week, 606 in all96%
  2. Spencer IslandSnohomish County, best the second week of June · 24 checklists that week, 943 in all88%
  3. Leque IslandSnohomish County, best early July · 52 checklists that week, 2,807 in all88%
  4. Clover IslandBenton County, best early May · 20 checklists that week, 705 in all85%

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

Best time of day

In Washington, the Cliff Swallow is most often listed on checklists started between 6 and 8 am (5.1% of those checklists).

0%2%4%6%8%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: 6.6% of 56744 checklists7 am: 4.4% of 133294 checklists8 am: 3.6% of 184196 checklists9 am: 3.2% of 186303 checklists10 am: 3.1% of 177063 checklists11 am: 2.8% of 154936 checklists12 pm: 2.6% of 138061 checklists1 pm: 2.5% of 127449 checklists2 pm: 2.4% of 121511 checklists3 pm: 2.3% of 107793 checklists4 pm: 2.7% of 82862 checklists5 pm: 3.8% of 57183 checklists6 pm: 4.5% 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%
March0.1%0.1%0.1%0.5%
April1.5%3.3%4.6%6.5%
May8.1%8.5%10%10%
June10%10%9.5%9.2%
July8.7%8.5%7.2%6.2%
August5.0%3.9%3.2%2.1%
September0.9%0.3%0.2%0.1%
October0.1%0.1%0%0%
November0.1%0.1%0.1%0.1%
December0.1%0.1%0%0%

Neighboring states

  • Oregon: arrives late March, 1 week earlier than Washington
  • Idaho: arrives early April, in the same week than Washington
  • Montana: arrives late April, 3 weeks later than Washington
  • Nevada: arrives early March, 4 weeks earlier than Washington

Common questions

When do Cliff Swallows arrive in Washington?
Cliff Swallows reach Washington in early April, are common by mid April, peak in early June (10% of checklists), and most are gone by early August.
When do Cliff Swallows leave Washington?
Most Cliff Swallows have left Washington by early August, when reports fall below half their usual rate. Stragglers are still reported until early September.
When is the best time to see a Cliff Swallow in Washington?
The Cliff Swallow is reported most often in early June, on about 10% of Washington checklists.
Where in Washington are Cliff Swallows seen most often?
By county, Adams County, Benton County, and Franklin County have the highest peak reporting rates for the Cliff Swallow (counties with at least 200 checklists).