Weather on September 18
Round Rock, TX
55 Years of Data
About This Date
September 18th in Round Rock, TX typically brings hot fall weather, with average highs around 91°F and lows near 68°F. Over 30 years of records, the warmest September 18th was in 1972 (86°F average), while the coldest was 1981 (61°F) — a 25°F range across recorded history. Rain or other precipitation has occurred on about 20% of September 18th dates historically, with the wettest September 18th recording 1.2" of rain.
Planning for September 18th in Round Rock, TX? Stay hydrated and seek shade during peak afternoon hours.
| Year | High | Low | Avg | Precip | Snow |
|---|---|---|---|---|---|
| 2025 | 96° | 69° | 83° | — | — |
| 2024 | 97° | 71° | 84° | — | — |
| 2023 | 91° | 65° | 78° | — | — |
| 2022 | 95° | 74° | 84° | — | — |
| 2021 | 94° | 68° | 81° | — | — |
| 2020 | 87° | 69° | 78° | — | — |
| 2019 | 88° | 70° | 79° | — | — |
| 2018 | 90° | 68° | 79° | — | — |
| 2017 | 91° | 72° | 81° | — | — |
| 2016 | 94° | 71° | 82° | — | — |
| 2015 | 93° | 74° | 83° | — | — |
| 2014 | 89° | 71° | 80° | 1.2" | — |
| 2013 | 94° | 70° | 82° | 0.01" | — |
| 2012 | 82° | 63° | 72° | — | — |
| 2011 | 92° | 70° | 81° | — | — |
| 2010 | 92° | 71° | 81° | 0.52" | — |
| 2009 | 81° | 66° | 73° | — | — |
| 2008 | 79° | 62° | 70° | 0.02" | — |
| 1982 | 99° | 68° | 83° | — | — |
| 1981coldest | 76° | 47° | 61° | — | — |
| 1980 | 98° | 68° | 83° | — | — |
| 1979 | 79° | 57° | 68° | 0.78" | — |
| 1978 | 94° | 70° | 82° | — | — |
| 1977 | 98° | 73° | 86° | — | — |
| 1976 | 92° | 70° | 81° | — | — |
| 1975 | 95° | 73° | 84° | — | — |
| 1974 | 87° | 70° | 78° | 0.03" | — |
| 1973 | 89° | 59° | 74° | — | — |
| 1972warmest | 96° | 75° | 86° | — | — |
| 1971 | 90° | 64° | 77° | — | — |
Round Rock, TX Temperature Range by Month
Average monthly highs and lows. The shaded band shows the typical daily temperature range.
Round Rock, TX Monthly Precipitation
Average rainfall and snowfall per month, in inches.
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.
Best Time to Visit Round Rock, TX
Most pleasant months in Round Rock, TX: February, March, April, October, November.
What to expect on September 18th
This page shows what actually happened each year. For the odds — typical high and low, and how often it stays dry — see the climatological outlook for this date.
September 18th outlook →