Merrimac climate

Merrimac Weather in September

NOAA 1991-2020 normals for Piedmont Rsch Stn, 24.8 km from Merrimac

Average highs run from 83°F on September 1 to 74°F on September 30, and lows from 63°F to 53°F. Normal precipitation for the month is 4.27 in over about 8 wet days.

September day by day

The normal high and low for each date, and the record, in °F.

Normal daily high and low temperature at Merrimac, in °F, with the record for each date.20406080100151015202530
  • Normal low
  • Normal high
  • Record high
  • Record low

September at a glance

Average high
79°F
Average low
59°F
Precipitation
4.27 in
Record high
99°FSep 5, 2023
Record low
38°FSep 20, 2020
Chance of a freeze
0%
Days of 90°F or more
2.3
Daylight
13 h 00 min to 11 h 50 min
Cloud cover
54%
Humidity
71%
Dew point
56°F
Wind
3.8 mph

Every day of the month

A wet day has at least 0.01 inch of precipitation; snow means at least 0.1 inch of snowfall.

DateNormal highNormal lowRecord highRecord lowChance wetChance of snow
Sep 183°F63°F94°F 201650°F 200927%0%
Sep 283°F63°F94°F 199849°F 200927%0%
Sep 382°F63°F95°F 202648°F 200927%0%
Sep 482°F63°F94°F 201847°F 202427%0%
Sep 582°F62°F99°F 202347°F 202427%0%
Sep 682°F62°F99°F 199846°F 200027%0%
Sep 781°F62°F97°F 202345°F 200027%0%
Sep 881°F62°F93°F 201647°F 201727%0%
Sep 981°F61°F96°F 201643°F 202427%0%
Sep 1081°F61°F96°F 201644°F 202427%0%
Sep 1180°F61°F94°F 201647°F 201026%0%
Sep 1280°F60°F96°F 199848°F 201226%0%
Sep 1380°F60°F96°F 199849°F 200226%0%
Sep 1479°F60°F94°F 199845°F 201426%0%
Sep 1579°F59°F95°F 201642°F 200126%0%
Sep 1679°F59°F95°F 199843°F 200126%0%
Sep 1778°F59°F90°F 199841°F 200026%0%
Sep 1878°F58°F88°F 201741°F 201326%0%
Sep 1978°F58°F88°F 201640°F 201326%0%
Sep 2077°F57°F89°F 199838°F 202026%0%
Sep 2177°F57°F91°F 199839°F 202027%0%
Sep 2277°F57°F88°F 201940°F 202027%0%
Sep 2376°F56°F90°F 201042°F 202027%0%
Sep 2476°F56°F92°F 201642°F 199827%0%
Sep 2576°F55°F94°F 201041°F 201227%0%
Sep 2675°F55°F93°F 201040°F 201227%0%
Sep 2775°F54°F99°F 199840°F 200127%0%
Sep 2874°F54°F90°F 199838°F 202227%0%
Sep 2974°F53°F83°F 201940°F 201326%0%
Sep 3074°F53°F90°F 199840°F 200326%0%

Chance of rain

The chance of at least 0.01 inch of precipitation on each date at Merrimac, in percent, and of at least 0.1 inch of snowfall.01020301102030
  • Chance of a wet day
  • Chance of snowfall

Sunrise and sunset

Times for 2026, local time (EDT).

September 1
sunrise 6:42 AM, sunset 7:42 PM
September 30
sunrise 7:07 AM, sunset 6:57 PM

Every day of September: sun and moon

Other months

Sources

Normals: NOAA NCEI U.S. Climate Normals, 1991-2020, station USC00446712 (Piedmont Rsch Stn), public domain. Records: NOAA GHCN-Daily, station USC00447985, every year on file, quality-flagged values removed. Cloud, humidity, wind and sunshine: NASA POWER (MERRA-2, CERES and GEWEX SRB), 1991-2020. The data was obtained from the National Aeronautics and Space Administration (NASA) Langley Research Center's Prediction Of Worldwide Energy Resources (POWER) project funded through the NASA Earth Science Division: POWER Daily API v2, accessed 2026-09-24. Sun and moon: computed with the NOAA solar equations and Meeus.