Roslyn weather by month
What a typical year looks like in Roslyn, Washington: average highs and lows, rain and snow, and the warmest and coldest days on record. Normals are the 1991–2020 averages at Stampede Pass, 15 km from Roslyn; records cover 1944–2026.
The year at a glance
- Precipitation a year
- 85 in2159 mm
- Snow a year
- Rare
- Last spring freeze
- May 19
- First fall freeze
- Oct 8
- Heating degree days
- 8,316
- Cooling degree days
- 100
Freeze dates are medians (half of years earlier, half later). Degree days use a 65°F base; HVAC design temperatures here are 10°−12° (heating, 99%) and 84°29° (cooling, 1%).
Month by month
Roslyn in January
Highs average 32°0° and lows 25°−4°, with 11.7 in297 mm of precipitation in a typical January.
- Record high
- 59°15° (1968)
- Record low
- −12°−24° (2024)
- Heating degree days
- 1128
- Cooling degree days
- 0
Roslyn in February
Highs average 35°2° and lows 26°−3°, with 7.9 in201 mm of precipitation in a typical February.
- Record high
- 59°15° (1988)
- Record low
- −10°−23° (1989)
- Heating degree days
- 970
- Cooling degree days
- 0
Roslyn in March
Highs average 40°5° and lows 29°−2°, with 8.8 in225 mm of precipitation in a typical March.
- Record high
- 65°18° (2024)
- Record low
- 1°−17° (1960)
- Heating degree days
- 942
- Cooling degree days
- 0
Roslyn in April
Highs average 46°8° and lows 33°0°, with 6.5 in164 mm of precipitation in a typical April.
- Record high
- 76°24° (1977)
- Record low
- 16°−9° (1951)
- Heating degree days
- 774
- Cooling degree days
- 0
Roslyn in May
Highs average 53°12° and lows 38°4°, with 4.7 in118 mm of precipitation in a typical May.
- Record high
- 86°30° (1986)
- Record low
- 20°−7° (1954)
- Heating degree days
- 594
- Cooling degree days
- 2
Roslyn in June
Highs average 60°15° and lows 43°6°, with 3.3 in84 mm of precipitation in a typical June.
- Record high
- 98°37° (2021)
- Record low
- 28°−2° (1950)
- Heating degree days
- 414
- Cooling degree days
- 8
Roslyn in July
Highs average 68°20° and lows 50°10°, with 1.3 in33 mm of precipitation in a typical July.
- Record high
- 93°34° (2006)
- Record low
- 30°−1° (1955)
- Heating degree days
- 224
- Cooling degree days
- 35
Roslyn in August
Highs average 69°21° and lows 51°11°, with 1.6 in40 mm of precipitation in a typical August.
- Record high
- 94°34° (2023)
- Record low
- 34°1° (1964)
- Heating degree days
- 198
- Cooling degree days
- 42
Roslyn in September
Highs average 63°17° and lows 47°8°, with 4 in100 mm of precipitation in a typical September.
- Record high
- 91°33° (1988)
- Record low
- 26°−3° (1972)
- Heating degree days
- 323
- Cooling degree days
- 13
Roslyn in OctoberThis month
Highs average 49°10° and lows 38°3°, with 9 in229 mm of precipitation in a typical October.
- Record high
- 80°27° (1988)
- Record low
- 15°−9° (1984)
- Heating degree days
- 665
- Cooling degree days
- 0
Roslyn in November
Highs average 38°3° and lows 30°−1°, with 13.7 in348 mm of precipitation in a typical November.
- Record high
- 63°17° (2008)
- Record low
- −5°−21° (1955)
- Heating degree days
- 940
- Cooling degree days
- 0
Roslyn in December
Highs average 32°0° and lows 24°−4°, with 12.6 in320 mm of precipitation in a typical December.
- Record high
- 64°18° (1980)
- Record low
- −21°−29° (1968)
- Heating degree days
- 1144
- Cooling degree days
- 0