Discovery Bay weather by month
What a typical year looks like in Discovery Bay, California: average highs and lows, rain and snow, and the warmest and coldest days on record. Normals are the 1991–2020 averages at Tracy Pumping Plant, 13 km from Discovery Bay; records cover 1955–2026.
The year at a glance
- Precipitation a year
- 12.4 in314 mm
- Snow a year
- Rare
- Last spring freeze
- Jan 30
- First fall freeze
- Dec 6
- Heating degree days
- 2,126
- Cooling degree days
- 1,598
Freeze dates are medians (half of years earlier, half later). Degree days use a 65°F base; HVAC design temperatures here are 30°−1° (heating, 99%) and 104°40° (cooling, 1%).
Month by month
Discovery Bay in January
Highs average 56°13° and lows 41°5°, with 2.5 in64 mm of precipitation in a typical January.
- Record high
- 74°23° (2021)
- Record low
- 18°−8° (1961)
- Heating degree days
- 515
- Cooling degree days
- 0
Discovery Bay in February
Highs average 62°17° and lows 44°7°, with 2.3 in59 mm of precipitation in a typical February.
- Record high
- 80°27° (2026)
- Record low
- 23°−5° (1989)
- Heating degree days
- 342
- Cooling degree days
- 0
Discovery Bay in March
Highs average 67°20° and lows 47°8°, with 1.6 in41 mm of precipitation in a typical March.
- Record high
- 91°33° (2026)
- Record low
- 25°−4° (1966)
- Heating degree days
- 245
- Cooling degree days
- 4
Discovery Bay in April
Highs average 73°23° and lows 50°10°, with 0.84 in21 mm of precipitation in a typical April.
- Record high
- 97°36° (1996)
- Record low
- 29°−2° (1995)
- Heating degree days
- 135
- Cooling degree days
- 36
Discovery Bay in May
Highs average 80°27° and lows 55°13°, with 0.52 in13 mm of precipitation in a typical May.
- Record high
- 107°42° (2021)
- Record low
- 34°1° (1968)
- Heating degree days
- 45
- Cooling degree days
- 129
Discovery Bay in June
Highs average 88°31° and lows 59°15°, with 0.13 in3.3 mm of precipitation in a typical June.
- Record high
- 112°44° (1961)
- Record low
- 37°3° (1988)
- Heating degree days
- 6
- Cooling degree days
- 268
Discovery Bay in July
Highs average 93°34° and lows 62°17°, with 0 in0 mm of precipitation in a typical July.
- Record high
- 112°44° (1961)
- Record low
- 44°7° (1966)
- Heating degree days
- 0
- Cooling degree days
- 391
Discovery Bay in August
Highs average 93°34° and lows 62°17°, with 0.01 in0.3 mm of precipitation in a typical August.
- Record high
- 111°44° (1971)
- Record low
- 42°6° (1956)
- Heating degree days
- 0
- Cooling degree days
- 378
Discovery Bay in September
Highs average 89°32° and lows 60°16°, with 0.08 in2 mm of precipitation in a typical September.
- Record high
- 112°44° (2022)
- Record low
- 40°4° (1968)
- Heating degree days
- 2
- Cooling degree days
- 287
Discovery Bay in OctoberThis month
Highs average 79°26° and lows 55°13°, with 0.67 in17 mm of precipitation in a typical October.
- Record high
- 103°39° (2024)
- Record low
- 30°−1° (1971)
- Heating degree days
- 45
- Cooling degree days
- 101
Discovery Bay in November
Highs average 66°19° and lows 46°8°, with 1.3 in34 mm of precipitation in a typical November.
- Record high
- 85°29° (1955)
- Record low
- 24°−4° (1993)
- Heating degree days
- 278
- Cooling degree days
- 4
Discovery Bay in December
Highs average 57°14° and lows 40°5°, with 2.4 in60 mm of precipitation in a typical December.
- Record high
- 74°23° (1977)
- Record low
- 17°−8° (1990)
- Heating degree days
- 513
- Cooling degree days
- 0