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Weather on December 18

Round Rock, TX

55 Years of Data

Avg High
63°F
Avg Low
40°F
Warmest
2021
71°F avg
Coldest
1975
31°F avg

About This Date

December 18th in Round Rock, TX typically brings mild winter weather, with average highs around 63°F and lows near 40°F. Over 30 years of records, the warmest December 18th was in 2021 (71°F average), while the coldest was 1975 (31°F) — a 40°F range across recorded history. Rain or other precipitation has occurred on about 20% of December 18th dates historically.

Planning for December 18th in Round Rock, TX? Great weather for outdoor activities.

Warming Trend
0.5°F per decade on this date
YearHighLowAvgPrecipSnow
202563°57°60°0.2"
202477°65°71°
202369°34°51°
202256°29°42°
2021warmest76°67°71°0.48"
202063°28°45°
201952°30°41°
201868°38°53°
201757°44°51°0.03"
201674°23°48°
201563°34°48°
201451°46°49°0.28"
201370°37°53°
201270°41°55°
201159°43°51°
201050°33°42°
200954°41°47°0.28"
200853°39°46°0.05"
198278°52°65°
198151°17°34°
198080°50°65°
197964°20°42°
197870°48°59°
197779°39°59°
197665°52°58°
1975coldest38°24°31°
197468°41°55°
197347°
197253°38°45°
197159°32°46°
30 years of data from GEORGETOWN

Round Rock, TX Temperature Range by Month

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

30°50°70°90°110°JFMAMJJASOND
Avg high Avg low

Round Rock, TX Monthly Precipitation

Average rainfall and snowfall per month, in inches.

0"7"14"JFMAMJJASOND57.4"0"
Rain (in) Snow (in)

Round Rock, TX 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 Round Rock, TX

Round Rock, TX 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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