Freeze risk at its highest Statistically Calgary's coldest month and the highest-consequence month of the year for a vacant property. Extended cold snaps below −25 °C are normal rather than exceptional, and a heating failure during one starts a countdown.
Typical daily highs around −3 °C and lows near −15 °C, with cold snaps regularly reaching −30 °C. Chinooks interrupt the cold several times most Januaries, producing swings of 20–30 °C within a day.
This month
- Increase visit frequency during any extended cold event.
- Record interior temperature at multiple points every visit.
- Confirm the furnace is running and clear exterior intake and exhaust terminations of snow, ice and frost.
- Check known cold spots — garages, basements, exterior-wall bathrooms, rooms over unheated space.
- Verify water shut-off state matches your instructions.
- Clear walks within 24 hours of snowfall as bylaw requires.
- Watch for ice damming after each chinook cycle.
Deep winter with chinook cycling
February
February combines January's cold with more frequent chinooks, and the cycling itself is the problem. Repeated melt and refreeze builds ice dams, concentrates meltwater at foundations, and loads and unloads roof edges over and over.
Similar cold to January with more frequent and pronounced chinook events. Temperature swings of 25–30 °C within 24 hours are routine.
This month
- Continue elevated visit frequency through cold events.
- Inspect roof edges from the ground for ice dam formation after each chinook.
- Confirm downspout discharge is clear and directed away from the foundation as meltwater runs.
- Watch for water staining at ceilings near exterior walls — the first sign of ice dam intrusion.
- Keep window wells clear of accumulated snow.
- Continue temperature and heating verification at every visit.
Freeze–thaw transition
March
March cycles above and below freezing almost daily, which is harder on a building than steady cold. It is also Calgary's snowiest month on average, and the snow is wet and heavy rather than dry.
Daily highs around freezing with overnight lows well below. Historically Calgary's snowiest month, with heavy wet snowfalls common.
This month
- Begin spring drainage observation: grade, window wells, downspout discharge.
- Confirm the sump pump operates and its discharge line is clear and not frozen.
- Watch for meltwater pooling near the foundation.
- Continue heating verification — March cold snaps still reach well below −20 °C.
- Observe for snow-load damage after heavy wet snowfalls, particularly branch damage.
- Continue ice dam monitoring.
Meltwater and basement moisture The accumulated snow of five months melts, often over ground that is still frozen. Water runs across the surface rather than into it, following whatever grade it finds — which is the month's entire risk in one sentence.
Rapid melt with continued freezing overnight. Significant late-season snowfalls remain common and are usually wet and heavy.
This month
- Check basements thoroughly at every visit — floors, wall bases, corners, stored items.
- Verify sump pump operation under actual load.
- Confirm downspouts are extended well clear of the foundation.
- Clear window wells and confirm covers are intact.
- Look for pooling and negative grade against foundation walls.
- Watch for efflorescence and damp drywall at floor level.
- Assess winter damage to trees, fencing and landscaping.
Growing season starts and so does severe weather. May brings the first thunderstorms with hail potential, while late-season snow remains entirely possible — Calgary has recorded significant May snowfalls many times.
Warming with high variability. First thunderstorms of the season, and late snowfall still possible.
This month
- Start lawn maintenance before the property visibly announces its vacancy.
- Coordinate irrigation start-up and walk the system for leaks and broken heads once pressurised.
- Complete spring cleanup of winter debris.
- Begin post-storm checks after any significant weather.
- Finish spring drainage assessment.
- Clear gutters of winter debris before the summer rains.
Calgary's wettest month and the start of peak hail season. June is when the corridor is most active, and storm cells are narrow enough that damage varies street by street.
Calgary's highest average precipitation. Frequent thunderstorms with hail potential, and occasional multi-day rain events.
This month
- Book a check after any hail or severe storm near the property.
- Document exterior condition promptly after events — timing matters.
- Confirm drainage is handling heavy rainfall without pooling at the foundation.
- Maintain lawn and yard on schedule.
- Check basements after heavy rain.
- Confirm outdoor items are secured against wind.
Hail continues, and the yard needs attention Peak hail season continues through July, alongside the practical business of keeping a property looking maintained through the growing season.
Warmest month, with continued thunderstorm and hail activity. Occasional extended dry periods.
This month
- Continue post-storm checks after hail and wind events.
- Maintain lawn and yard consistently.
- Water plants and containers per instructions, subject to any restrictions in force.
- Verify irrigation is running correctly and not leaking.
- Keep mail, flyers and parcels cleared.
- Confirm interior temperature is not climbing to levels that damage finishes or contents.
Late storms and early preparation Storm activity continues into August while the season starts turning. A good month to plan fall winterisation before schedules fill.
Warm with continued thunderstorm potential. Early frost possible late in the month in outlying areas.
This month
- Continue storm checks.
- Maintain lawn, yard and plant watering.
- Book fall irrigation blowout now — providers fill up through September.
- Schedule gutter cleaning for early fall.
- Begin planning departure preparation if leaving for the winter.
- Consider a pre-vacancy professional inspection while trades are still available.
Winterisation season starts The highest-leverage month of the year for a property heading into an Alberta winter. Almost every January failure has a September prevention step, and Calgary has recorded hard freezes and significant snowfall in September more than once.
Cooling with first frosts. Early snowfall entirely possible — Calgary has seen significant September snow events.
This month
- Shut off exterior faucets from inside and drain them.
- Book and complete irrigation blowout.
- Clear gutters and confirm downspout extensions.
- Service the heating system before the first cold, not during it.
- Replace furnace filters.
- Clear leaves from grade, window wells and drainage paths.
- Store outdoor furniture and secure loose items.
- Seal pest entry points before the fall push.
When most snowbird vacancies begin, and the month in which the property setup that will carry through to April gets made. Everything not done now compounds for six months.
Cold arriving in earnest with regular freezing overnight. Significant snowfall common.
This month
- Complete departure preparation with a full photographic and video baseline.
- Confirm water shut-off arrangements and document them.
- Set the thermostat to your winter instruction and photograph it.
- Verify heating operates before you leave.
- Arrange snow clearing for the season, and arrange for it to be verified.
- Confirm emergency contacts, access arrangements and authorisation limits.
- Call your broker about vacancy conditions before you go.
- Book the visit schedule and confirm the first visit date.
Heating verification and first deep cold The first serious cold of the season arrives, and it is the first real test of whether the property was prepared properly. Problems that surface now are far cheaper than the same problems in January.
Sustained below-freezing temperatures establish. First deep cold events common, sometimes reaching −25 °C or lower.
This month
- Verify heating is operating under actual load and holding the set point.
- Record interior temperature at multiple points.
- Clear exterior intake and exhaust terminations of snow and frost.
- Confirm snow clearing is happening as arranged.
- Check for drafts and cold spots that emerged with the first real cold.
- Verify the water shut-off state.
- Watch for early pest evidence as animals seek shelter.
Freeze protection and holiday-season vacancy Deep cold establishes for the season, and December adds a second factor: a high proportion of properties in the city are empty at once over the holidays, which is not lost on anyone paying attention.
Consistently cold with extended snaps below −20 °C. Chinooks interrupt periodically.
This month
- Maintain elevated visit frequency through cold events.
- Continue temperature and heating verification at every visit.
- Clear walks and driveway as bylaw requires.
- Keep parcels and mail collected — December delivery volume makes an accumulation obvious.
- Vary lighting timers rather than leaving a fixed pattern.
- Ensure the property does not visibly signal that nobody has been there for weeks.