Millbrae weather by month
What a typical year looks like in Millbrae, California: average highs and lows, rain and snow, and the warmest and coldest days on record. Normals are the 1991–2020 averages at San Francisco International Airport, 4 km from Millbrae; records cover 1945–2026.
The year at a glance
- Precipitation a year
- 19.6 in499 mm
- Snow a year
- Rare
- Last spring freeze
- Rare
- First fall freeze
- Rare
- Heating degree days
- 2,476
- Cooling degree days
- 201
Freeze dates are medians (half of years earlier, half later). Degree days use a 65°F base; HVAC design temperatures here are 38°3° (heating, 99%) and 90°32° (cooling, 1%).
Month by month
Millbrae in January
Highs average 58°14° and lows 45°7°, with 3.9 in99 mm of precipitation in a typical January.
- Record high
- 74°23° (2015)
- Record low
- 26°−3° (1949)
- Heating degree days
- 426
- Cooling degree days
- 0
Millbrae in February
Highs average 61°16° and lows 46°8°, with 4 in101 mm of precipitation in a typical February.
- Record high
- 78°26° (2022)
- Record low
- 30°−1° (1949)
- Heating degree days
- 323
- Cooling degree days
- 0
Millbrae in March
Highs average 63°17° and lows 48°9°, with 2.7 in69 mm of precipitation in a typical March.
- Record high
- 89°32° (2026)
- Record low
- 31°−1° (1966)
- Heating degree days
- 296
- Cooling degree days
- 1
Millbrae in April
Highs average 66°19° and lows 49°10°, with 1.4 in35 mm of precipitation in a typical April.
- Record high
- 92°33° (1981)
- Record low
- 36°2° (1955)
- Heating degree days
- 234
- Cooling degree days
- 5
Millbrae in May
Highs average 68°20° and lows 52°11°, with 0.48 in12 mm of precipitation in a typical May.
- Record high
- 97°36° (1984)
- Record low
- 39°4° (1950)
- Heating degree days
- 170
- Cooling degree days
- 14
Millbrae in June
Highs average 72°22° and lows 54°12°, with 0.14 in3.6 mm of precipitation in a typical June.
- Record high
- 105°41° (2000)
- Record low
- 43°6° (1954)
- Heating degree days
- 97
- Cooling degree days
- 23
Millbrae in July
Highs average 73°23° and lows 55°13°, with 0 in0 mm of precipitation in a typical July.
- Record high
- 99°37° (1985)
- Record low
- 44°7° (1951)
- Heating degree days
- 58
- Cooling degree days
- 26
Millbrae in August
Highs average 73°23° and lows 56°14°, with 0.04 in1 mm of precipitation in a typical August.
- Record high
- 99°37° (2010)
- Record low
- 45°7° (1952)
- Heating degree days
- 44
- Cooling degree days
- 41
Millbrae in September
Highs average 75°24° and lows 56°13°, with 0.07 in1.8 mm of precipitation in a typical September.
- Record high
- 104°40° (2017)
- Record low
- 41°5° (1950)
- Heating degree days
- 46
- Cooling degree days
- 56
Millbrae in OctoberThis month
Highs average 72°22° and lows 53°12°, with 0.79 in20 mm of precipitation in a typical October.
- Record high
- 99°37° (1987)
- Record low
- 37°3° (1949)
- Heating degree days
- 100
- Cooling degree days
- 33
Millbrae in November
Highs average 64°18° and lows 49°9°, with 2 in52 mm of precipitation in a typical November.
- Record high
- 85°29° (1967)
- Record low
- 31°−1° (1954)
- Heating degree days
- 260
- Cooling degree days
- 2
Millbrae in December
Highs average 58°15° and lows 45°7°, with 4.1 in105 mm of precipitation in a typical December.
- Record high
- 75°24° (1958)
- Record low
- 24°−4° (1972)
- Heating degree days
- 422
- Cooling degree days
- 0