Weather on July 18
Boise, ID
55 Years of Data
Avg High
92°F
Avg Low
61°F
Warmest
2009
87°F avg
Coldest
1987
59°F avg
About This Date
July 18th in Boise, ID typically brings hot summer weather, with average highs around 92°F and lows near 61°F — a 31°F daily swing. Over 55 years of records, the warmest July 18th was in 2009 (87°F average), while the coldest was 1987 (59°F) — a 28°F range across recorded history. Rain or other precipitation has occurred on about 4% of July 18th dates historically, with the wettest July 18th recording 0.61" of rain. The last decade has been 4.9°F warmer on this date compared to 20-30 years ago.
The last decade has been 4.9°F warmer on this date compared to 20-30 years ago.
Planning for July 18th in Boise, ID? Stay hydrated and seek shade during peak afternoon hours.
Warming Trend
1.3°F per decade on this date
| Year | High | Low | Avg | Precip | Snow |
|---|---|---|---|---|---|
| 2025 | 97° | 65° | 81° | — | — |
| 2024 | 102° | 72° | 87° | — | — |
| 2023 | 94° | 60° | 77° | — | — |
| 2022 | 90° | 67° | 78° | — | — |
| 2021 | 101° | 67° | 84° | — | — |
| 2020 | 90° | 59° | 74° | — | — |
| 2019 | 87° | 62° | 75° | — | — |
| 2018 | 99° | 68° | 83° | — | — |
| 2017 | 96° | 60° | 78° | — | — |
| 2016 | 96° | 62° | 79° | — | — |
| 2015 | 86° | 56° | 71° | — | — |
| 2014 | 94° | 64° | 79° | — | — |
| 2013 | 100° | 63° | 81° | — | — |
| 2012 | 97° | 64° | 80° | — | — |
| 2011 | 97° | 60° | 78° | — | — |
| 2010 | 96° | 64° | 80° | — | — |
| 2009warmest | 106° | 68° | 87° | — | — |
| 2008 | 90° | 61° | 75° | — | — |
| 2007 | 97° | 68° | 82° | — | — |
| 2006 | 95° | 61° | 78° | — | — |
| 2005 | 98° | 61° | 79° | — | — |
| 2004 | 85° | 70° | 77° | — | — |
| 2003 | 103° | 68° | 85° | — | — |
| 2002 | 88° | 70° | 79° | — | — |
| 2001 | 81° | 53° | 67° | — | — |
| 2000 | 89° | 66° | 78° | 0.08" | — |
| 1999 | 84° | 51° | 68° | — | — |
| 1998 | 99° | 68° | 83° | — | — |
| 1997 | 72° | 58° | 65° | — | — |
| 1996 | 80° | 51° | 66° | — | — |
| 1995 | 93° | 62° | 78° | — | — |
| 1994 | 95° | 60° | 78° | — | — |
| 1993 | 82° | 42° | 62° | — | — |
| 1992 | 95° | 65° | 80° | — | — |
| 1991 | 88° | 53° | 70° | — | — |
| 1990 | 94° | 66° | 80° | — | — |
| 1989 | 99° | 61° | 80° | — | — |
| 1988 | 90° | 48° | 69° | — | — |
| 1987coldest | 68° | 50° | 59° | — | — |
| 1986 | 90° | 54° | 72° | — | — |
| 1985 | 93° | 53° | 73° | — | — |
| 1984 | 89° | 68° | 79° | — | — |
| 1983 | 91° | 49° | 70° | — | — |
| 1982 | 91° | 56° | 73° | — | — |
| 1981 | 92° | 63° | 77° | — | — |
| 1980 | 87° | 52° | 69° | — | — |
| 1979 | 101° | 65° | 83° | — | — |
| 1978 | 87° | 54° | 70° | — | — |
| 1977 | 94° | 56° | 75° | — | — |
| 1976 | 75° | 58° | 66° | 0.61" | — |
| 1975 | 89° | 57° | 73° | — | — |
| 1974 | 101° | 65° | 83° | — | — |
| 1973 | 95° | 63° | 79° | — | — |
| 1972 | 95° | 57° | 76° | — | — |
| 1971 | 86° | 70° | 78° | — | — |
55 years of data from BOISE AIR TERMINAL