Gaithersburg weather by month
What a typical year looks like in Gaithersburg, Maryland: average highs and lows, rain and snow, and the warmest and coldest days on record. Normals are the 1991–2020 averages at DALECARLIA RESERVOIR, 24 km from Gaithersburg; records cover 1948–2026.
The year at a glance
- Precipitation a year
- 48.5 in1232 mm
- Snow a year
- 6 in15 cm
- Last spring freeze
- Apr 6
- First fall freeze
- Nov 2
- Heating degree days
- 4,507
- Cooling degree days
- 1,337
Freeze dates are medians (half of years earlier, half later). Degree days use a 65°F base; HVAC design temperatures here are 11°−12° (heating, 99%) and 98°37° (cooling, 1%).
Month by month
Gaithersburg in January
Highs average 43°6° and lows 26°−4°, with 3.3 in84 mm of precipitation and 2.9 in7.4 cm of snow in a typical January.
- Record high
- 79°26° (1950)
- Record low
- −11°−24° (1985)
- Heating degree days
- 955
- Cooling degree days
- 0
Gaithersburg in February
Highs average 46°8° and lows 27°−3°, with 3.2 in82 mm of precipitation and 1.4 in3.6 cm of snow in a typical February.
- Record high
- 82°28° (2018)
- Record low
- −1°−18° (1979)
- Heating degree days
- 788
- Cooling degree days
- 0
Gaithersburg in March
Highs average 55°13° and lows 34°1°, with 4.2 in105 mm of precipitation and 0.7 in1.8 cm of snow in a typical March.
- Record high
- 91°33° (1998)
- Record low
- 5°−15° (1960)
- Heating degree days
- 649
- Cooling degree days
- 2
Gaithersburg in April
Highs average 68°20° and lows 44°6°, with 3.5 in90 mm of precipitation in a typical April.
- Record high
- 95°35° (2002)
- Record low
- 17°−8° (2000)
- Heating degree days
- 305
- Cooling degree days
- 23
Gaithersburg in May
Highs average 76°24° and lows 54°12°, with 4.4 in113 mm of precipitation in a typical May.
- Record high
- 98°37° (1996)
- Record low
- 23°−5° (1992)
- Heating degree days
- 107
- Cooling degree days
- 97
Gaithersburg in June
Highs average 84°29° and lows 63°17°, with 4.2 in108 mm of precipitation in a typical June.
- Record high
- 100°38° (1988)
- Record low
- 30°−1° (1992)
- Heating degree days
- 13
- Cooling degree days
- 265
Gaithersburg in July
Highs average 88°31° and lows 68°20°, with 5.1 in130 mm of precipitation in a typical July.
- Record high
- 103°39° (1954)
- Record low
- 42°6° (1996)
- Heating degree days
- 0
- Cooling degree days
- 406
Gaithersburg in August
Highs average 86°30° and lows 66°19°, with 4.4 in112 mm of precipitation in a typical August.
- Record high
- 105°41° (1997)
- Record low
- 41°5° (1986)
- Heating degree days
- 2
- Cooling degree days
- 351
Gaithersburg in September
Highs average 79°26° and lows 59°15°, with 4.5 in115 mm of precipitation in a typical September.
- Record high
- 99°37° (1953)
- Record low
- 31°−1° (1956)
- Heating degree days
- 38
- Cooling degree days
- 166
Gaithersburg in OctoberThis month
Highs average 68°20° and lows 47°8°, with 4.4 in112 mm of precipitation in a typical October.
- Record high
- 95°35° (2007)
- Record low
- 16°−9° (1992)
- Heating degree days
- 262
- Cooling degree days
- 26
Gaithersburg in November
Highs average 56°14° and lows 36°2°, with 3.3 in84 mm of precipitation in a typical November.
- Record high
- 87°31° (1971)
- Record low
- 8°−13° (1992)
- Heating degree days
- 559
- Cooling degree days
- 1
Gaithersburg in December
Highs average 47°8° and lows 30°−1°, with 3.8 in97 mm of precipitation and 0.8 in2 cm of snow in a typical December.
- Record high
- 82°28° (1998)
- Record low
- −2°−19° (1989)
- Heating degree days
- 829
- Cooling degree days
- 0