Merrimac Massachusetts Climate Data

Monthly Average Climate Data for Merrimac Massachusetts

Switch Data to Celsius/Metric Units
MonthAvg. LowAvg. HighAvg. Precip
January16.1 °F34.9 °F3.66 in.
February17.8 °F37.5 °F3.55 in.
March25.3 °F44.8 °F4.69 in.
April35.4 °F57.3 °F4.28 in.
May45.6 °F67.6 °F3.9 in.
June55.2 °F76.7 °F4.31 in.
July60.9 °F82.6 °F3.57 in.
August59.1 °F81.2 °F3.48 in.
September51.5 °F74.0 °F3.9 in.
October40.0 °F61.8 °F4.97 in.
November31.1 °F50.7 °F3.88 in.
December22.6 °F40.3 °F4.71 in.
Annual38.4 °F59.1 °F48.9 in.

Climate Data for Merrimac Massachusetts

Average First Frost DateOct. 11 - Oct. 20
Average Last Frost DateMay 21 - May 31
Average Days With Frost125-150 Days
Plant Hardiness Zone - 2023Zone 6a : -10°F to -5°F
Plant Hardiness Zone - 2012Zone 6a : -10°F to -5°F
Current Drought ConditionsNormal
Köppen Climate ClassificationDfb - Humid Continental Mild Summer, Wet All Year