Delta climate

Delta Weather in December

NOAA 1991-2020 normals for Conowingo Dam, 15.2 km from Delta

Average highs run from 49°F on December 1 to 41°F on December 31, and lows from 33°F to 27°F. Normal precipitation for the month is 4.04 in over about 10 wet days.

December day by day

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

Normal daily high and low temperature at Delta, in °F, with the record for each date.-20020406080151015202530
  • Normal low
  • Normal high
  • Record high
  • Record low

December at a glance

Average high
45°F
Average low
31°F
Precipitation
4.04 in
Snowfall
4.4 in
Record high
77°FDec 7, 1998
Record low
-2°FDec 31, 1963
Chance of a freeze
100%
Daylight
9 h 34 min to 9 h 25 min
Cloud cover
64%
Humidity
84%
Dew point
31°F
Wind
8.7 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
Dec 149°F33°F68°F 200610°F 197629%4%
Dec 249°F33°F72°F 20068°F 196730%5%
Dec 349°F33°F75°F 19988°F 197630%5%
Dec 448°F33°F75°F 19986°F 197630%5%
Dec 548°F33°F75°F 199811°F 197630%5%
Dec 648°F33°F68°F 200113°F 197630%5%
Dec 747°F32°F77°F 199810°F 200230%5%
Dec 847°F32°F77°F 199811°F 200230%6%
Dec 947°F32°F64°F 19519°F 198931%6%
Dec 1047°F32°F68°F 19397°F 198931%6%
Dec 1146°F32°F68°F 19997°F 196831%6%
Dec 1246°F32°F64°F 20216°F 198831%6%
Dec 1346°F31°F65°F 19907°F 196031%6%
Dec 1445°F31°F62°F 20209°F 195831%7%
Dec 1545°F31°F63°F 19758°F 196031%7%
Dec 1645°F31°F68°F 19716°F 195131%7%
Dec 1745°F31°F60°F 20004°F 195131%7%
Dec 1844°F30°F61°F 19374°F 194531%7%
Dec 1944°F30°F70°F 20061°F 198932%7%
Dec 2044°F30°F59°F 19577°F 196032%7%
Dec 2144°F30°F61°F 2018-1°F 194232%7%
Dec 2243°F30°F63°F 2018-1°F 198932%8%
Dec 2343°F29°F64°F 19900°F 196032%8%
Dec 2443°F29°F62°F 19901°F 198932%8%
Dec 2543°F29°F67°F 19643°F 198932%8%
Dec 2642°F29°F65°F 19642°F 198332%8%
Dec 2742°F28°F61°F 20152°F 198932%8%
Dec 2842°F28°F64°F 19464°F 195033%8%
Dec 2942°F28°F74°F 19847°F 196333%9%
Dec 3042°F28°F68°F 19715°F 196333%9%
Dec 3141°F27°F62°F 1971-2°F 196333%9%

Chance of rain

The chance of at least 0.01 inch of precipitation on each date at Delta, in percent, and of at least 0.1 inch of snowfall.0102030401102030
  • Chance of a wet day
  • Chance of snowfall

Sunrise and sunset

Times for 2026, local time (EST).

December 1
sunrise 7:07 AM, sunset 4:41 PM
December 31
sunrise 7:26 AM, sunset 4:51 PM

Every day of December: sun and moon

Other months

Sources

Normals: NOAA NCEI U.S. Climate Normals, 1991-2020, station USC00182060 (Conowingo Dam), public domain. Records: NOAA GHCN-Daily, station USC00182060, 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.