Moving from Calgary to Seattle
A climate comparison of two homes: Alberta to Washington. The dates below come from the nearest official weather station to each place.
Climate Match
Freezing months go from 5 months to 0 months.
Calgary, AB to Seattle, WA
The full comparison
| Measure | From | To | Change |
|---|---|---|---|
| Months below freezing | 5 months | 0 months | 5 fewer |
| Frost-free season | 117 days | 247 days | 130 days longer |
| Last spring frost | May 21 | March 13 | 69 days earlier |
| Coldest month | -7C in January | 6C in December | 13C warmer |
| Warmest month | 17C in July | 20C in August | 3C hotter |
Moving from Calgary to Seattle reshapes the home year. Winters get 13C warmer. Summers get 3C hotter. Your growing season is 130 days longer. Plan on a new rhythm for the house and garden.
What changes about the house
- Heating: expect a longer or deeper heating season. Service the furnace or boiler before the first cold snap, and budget for higher heating bills.
- Cooling: hotter peaks make air conditioning or shading more important. Check attic insulation and window sealing so the house does not trap heat.
- Garden: a longer frost-free season opens more crop choices and succession sowings. Raised beds warm earlier in spring.
- Snow and ice: fewer freezing months reduce roof and driveway risk, but one surprise storm still happens. Keep basic winter tools for the odd freeze.
Season by season
Spring starts earlier
Your last spring frost moves from May 21 to March 13, 69 days earlier. Start planting and outdoor prep sooner.
Summers run hotter
The warmest month goes from 17C in July to 20C in August. Air conditioning, shading, and cooling-load planning matter more.
Winters turn milder
Winter coldest month goes from -7C in January to 6C in December; freezing months go from 5 months to 0 months. Budget for more heating, snow removal, and ice-dam prevention.
Tools for both places
Moving from Calgary to Seattle, answered
What is the biggest climate change from Calgary to Seattle?
Freezing months go from 5 months to 0 months. That is the largest shift in the 30-year climate record.
How are these numbers computed?
From official 30-year climate normals at the nearest station to each place: Calgary Intl Airport near Calgary and Seattle Boeing Fld near Seattle. They are planning averages, not forecasts; local microclimates can run a week or two off the station record.
Does the comparison work in reverse?
Yes. Open the comparison tool and swap the two places; the deltas reverse direction but the match score stays the same.
Method and sources
Temperatures and frost dates are from the 30-year climate normals at Calgary Intl Airport (near Calgary, AB) and Seattle Boeing Fld (near Seattle, WA). Canadian data is from Environment and Climate Change Canada; United States data is from NOAA NCEI. These are planning averages, not forecasts. See the methodology page for the full calculation.