Portland/Troutdale Arpt climate by month
Averages and records for each calendar month at Portland/Troutdale Arpt, United States, from 1998 to 2026. The warmest month is August, averaging 28.4°C; the coolest is December at 7.8°C.
| Month | Avg high | Avg low | Record high | Record low | Years |
|---|---|---|---|---|---|
| January | 8.0°C | 2.7°C | 19.4°C18 January 2005 | −9.9°C13 January 2024 | 28 / 28 |
| February | 9.9°C | 2.8°C | 18.9°C22 February 2002 | −7.7°C20 February 2006 | 28 / 28 |
| March | 13.3°C | 4.2°C | 25.6°C26 March 2025 | −3.3°C1 March 2002 | 28 / 28 |
| April | 16.5°C | 5.8°C | 31.1°C19 April 2016 | −2.7°C2 April 2008 | 27 / 28 |
| May | 20.5°C | 8.9°C | 35.6°C22 May 2001 | 1.1°C10 May 1999 | 28 / 28 |
| June | 23.8°C | 11.7°C | 46.7°C28 June 2021 | 4.4°C14 June 2025 | 28 / 28 |
| July | 28.2°C | 13.8°C | 40.6°C21 July 2006 | 7.2°C5 July 1999 | 29 / 29 |
| August | 28.4°C | 13.9°C | 43.3°C14 August 2023 | 6.7°C28 August 2000 | 29 / 29 |
| September | 24.7°C | 11.3°C | 36.7°C11 September 2013 | 2.8°C27 September 1999 | 28 / 29 |
| October | 17.8°C | 8.0°C | 31.1°C2 October 2022 | −1.6°C28 October 2019 | 28 / 28 |
| November | 11.6°C | 5.3°C | 21.7°C13 November 1999 | −9.3°C24 November 2010 | 28 / 28 |
| December | 7.8°C | 2.8°C | 20.6°C4 December 2023 | −10.5°C9 December 2013 | 28 / 28 |
Years shows the number behind the average high, then the number holding a record for that month. They differ because a year contributes an average only when the month has at least 25 days of readings, while a single reading is enough to set a record. The average low is withheld on the same 25-day rule and is counted separately again; it is shown as a dash where the archive cannot support it. Across the twelve months here the averages rest on 27 to 29 years each.
See what Portland/Troutdale Arpt is doing right now
Every figure on this page is computed from NOAA GHCN-Daily observations stored per station, per year, per month. Nothing is modelled, interpolated or estimated, and a month the archive never covered is left out rather than filled in. A station appears here only once all twelve months carry an average from at least 10 years. See how this is built.