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Weather on December 31

Hillsboro, OR

55 Years of Data

Avg High
44°F
Avg Low
32°F
Warmest
1980
54°F avg
Coldest
1978
18°F avg

About This Date

December 31st in Hillsboro, OR typically brings chilly winter weather, with average highs around 44°F and lows near 32°F. Over 55 years of records, the warmest December 31st was in 1980 (54°F average), while the coldest was 1978 (18°F) — a 36°F range across recorded history. Precipitation has occurred on 55% of recorded December 31st dates, with snow falling 2% of the time. The last decade has been 3.4°F cooler on this date compared to 20-30 years ago.

The last decade has been 3.4°F cooler on this date compared to 20-30 years ago.

Planning for December 31st in Hillsboro, OR? Bring layers as temperatures can vary throughout the day. Consider bringing rain gear or an umbrella.

Warming Trend
0.3°F per decade on this date
YearHighLowAvgPrecipSnow
202547°26°36°
202451°33°42°0.13"
202344°40°42°
202249°36°42°0.2"
202139°24°32°0.1"
202051°45°48°0.1"
201950°39°45°0.51"
201846°28°37°
201750°25°38°
201635°24°30°0.25"
201538°31°35°
201439°19°29°
201348°35°42°0.05"
201235°25°30°0.03"
201139°27°33°
201035°22°29°
200948°31°40°2.03"
200845°39°42°0.15"
200740°28°34°
200641°27°34°
200551°44°48°0.64"
200443°31°37°1.47"
200339°31°35°0.51"
200247°41°44°3.53"
200145°30°37°0.56"
200046°37°42°0.08"
199944°37°41°0.81"
199854°36°45°
199751°37°44°0.05"
199658°48°53°3.96"
199555°40°47°
199443°34°38°
199344°35°40°1.07"
199238°28°33°0.3"1"
199147°31°39°
199030°15°23°
198944°36°40°
198847°34°40°0.25"
198735°23°29°0.2"
198645°36°40°0.25"
198540°30°35°
198446°27°36°
198337°32°35°0.23"
198241°23°32°
198140°31°35°0.1"
1980warmest62°46°54°0.05"
197948°38°43°0.76"
1978coldest21°14°18°
197741°30°36°
197648°24°36°
197545°30°37°
197439°32°36°
197342°32°37°0.08"
197247°33°40°
197143°38°40°0.03"
55 years of data from HILLSBORO

Hillsboro, OR Temperature Range by Month

Average monthly highs and lows. The shaded band shows the typical daily temperature range.

30°40°50°60°70°80°90°JFMAMJJASOND
Avg high Avg low

Hillsboro, OR Monthly Precipitation

Average rainfall and snowfall per month, in inches.

0"4.1"8.2"JFMAMJJASOND1.7"0"
Rain (in) Snow (in)

Hillsboro, OR Daily Temperature Calendar

Average daily high temperature for every day of the year. Each cell is the climatological mean for that calendar day across 55 years of NOAA data.

151015202531JanFebMarAprMayJunJulAugSepOctNovDec
Cooler
Hotter
20°40°60°80°100°

Best Time to Visit Hillsboro, OR

Hillsboro, OR has no months that meet our "pleasant" threshold — every season has tradeoffs.

Jan
Feb
Mar
Apr
May
Jun
Jul
Aug
Sep
Oct
Nov
Dec
Pleasant (65-82°F, ≤2.5" rain) Mild Less ideal

Browse Weather History

Weather data provided by NOAA Climate Data Online. Not for critical planning.

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