Yellowknife in September
In September, Yellowknife averages 11°C (52°F) during the day and 6°C (42°F) at night, with frequent rain — about 14 days of the month see precipitation (28 mm total).
ShoulderConditions are cool — bring a jacket for evenings. Plan for unsettled weather and bring rain gear.
September is one of the wetter and less comfortable months in Yellowknife. If your dates are flexible, consider a different time of year.
How September compares to the rest of the year in Yellowknife
September is in the middle of the year for warmth in Yellowknife (4th of 12) and one of the wettest months (3rd of 12). Daytime temperature runs 11°C above the annual average (0°C). September runs 7°C cooler than August (18°C) and cools 9°C in October (2°C).
September sunrise & sunset in Yellowknife
Times shown for Yellowknife local time (America/Yellowknife), calculated for the 15th of September. They shift by a few minutes day to day across the month.
Photography light in Yellowknife — September
Golden-hour and blue-hour windows for the 15th of September, in Yellowknife's local time. Use these for soft warm light (golden) or cool architectural twilight (blue).
📅 When to book — Yellowknife in September
Travel writers usually only tell you when to go. Here's when to book flights and lodging for the best mix of price and availability, based on September's tier (Shoulder) and Yellowknife's popularity.
Crowds & pricing — September in Yellowknife
Yellowknife is in a shoulder season month — fewer crowds, slightly lower prices, and a calmer atmosphere than peak weeks. Most major sights stay open with normal hours, though a handful of seasonal restaurants or boat trips may run reduced schedules. Many regulars consider these months the best time to visit because you trade a small amount of weather reliability for a much more pleasant on-the-ground experience.
Sun & mosquito risk — September in Yellowknife
UV is a clear-sky sea-level estimate — clouds, altitude, and reflective surfaces (snow, water) shift it ±30%. Mosquito risk is climate-derived only; for current disease advisories (dengue, malaria, zika) check the CDC or WHO travel pages before your trip.
Yellowknife in other months
| Month | Avg high | Avg low | Rainfall | Rain days | Snow days |
|---|---|---|---|---|---|
| January | -21°C / -5°F | -26°C / -15°F | 15 mm | 12 | — |
| February | -22°C / -7°F | -28°C / -19°F | 7 mm | 9 | — |
| March | -12°C / 10°F | -20°C / -3°F | 12 mm | 9 | — |
| April | -2°C / 28°F | -10°C / 14°F | 12 mm | 9 | — |
| May | 11°C / 51°F | 1°C / 34°F | 25 mm | 10 | — |
| June | 19°C / 65°F | 9°C / 49°F | 33 mm | 13 | — |
| July | 21°C / 70°F | 13°C / 56°F | 40 mm | 12 | — |
| August | 18°C / 65°F | 12°C / 53°F | 54 mm | 18 | — |
| September | 11°C / 52°F | 6°C / 42°F | 28 mm | 14 | — |
| October | 2°C / 36°F | -2°C / 29°F | 25 mm | 15 | — |
| November | -10°C / 15°F | -15°C / 4°F | 20 mm | 12 | — |
| December | -18°C / -1°F | -24°C / -12°F | 14 mm | 9 | — |
Other cities with similar September weather
🌍 See the full ranked list of climate twins for Yellowknife in September →
Frequently asked questions
How hot is Yellowknife in September?
In September, Yellowknife averages a high of 11°C (52°F) and a low of 6°C (42°F) — generally cool.
Does it rain a lot in Yellowknife in September?
September can be fairly wet in Yellowknife, with about 14 rainy days on average.
Is September a good time to visit Yellowknife?
September is cool but on the rainy side. It suits travelers who are comfortable with cool weather; check the month-by-month ranking to compare it against the rest of the year.
What should I pack for Yellowknife in September?
Pack a warm jacket and layers, plus a compact umbrella or rain jacket. See the full September packing list for Yellowknife for a complete, climate-based checklist.
Check the live 10-day forecast and sunrise/sunset.