Lewiston, ID

Idaho · Records since 1881–2026

☁️ 75°F Feels like 72°
Currently in Lewiston
As of 11:00 AM PDT

Records for September 11

🔥 Record High

103°F

September 11, 1944

+21° from 82° normal

❄ Record Low

36°F

September 11, 1895

-18° from 54° normal
🌞 Normal high: 82°F 🌑 Normal low: 54°F 1991–2020 normals

All-Time Records — Lewiston

🔥
117°F
Hottest Day Ever
Jul 27, 1939
❄
-23°F
Coldest Day Ever
Dec 13, 1919
🌧
2.71"
Wettest Day Ever
Dec 13, 1882
☃
11.0"
Most Snow in One Day
Feb 2, 1916

First & Last Dates — Lewiston

How early and how late each seasonal turning point has ever arrived, across the full period of record

Jan Feb Mar Apr May Jun Jul Aug Sep Oct Nov Dec
Range ever recorded Normal date (1991–2020)
255 days
Longest growing season
1990
130 days
Shortest growing season
1895
196 days
Normal growing season
1991–2020 average

Top 10 Record Highs — September 11

# Temp Date
🏆 103°F September 11, 1944
2 101°F September 11, 1937
3 99°F September 11, 2013
4 99°F September 11, 1953
5 98°F September 11, 2011
6 97°F September 11, 1996
7 96°F September 11, 1973
8 96°F September 11, 1943
9 96°F September 11, 1940
10 95°F September 11, 1963

Top 5 Record Lows — September 11

# Temp Date
🥶 36°F September 11, 1895
2 39°F September 11, 1910
3 41°F September 11, 2014
4 41°F September 11, 1949
5 41°F September 11, 1913
About this data — Records are sourced from the NOAA Threadex dataset via RCC ACIS, a quality-controlled record for long-term climate stations. Threadex adjusts for station relocations and observation-time changes, making records comparable across all years since 1881–2026. Climate normals represent the 1991–2020 average.

Heat Wave Summary — Lewiston

threshold: 100°F (90th percentile of historical Jun–Aug highs)
4.4
Avg heat wave length
days (historical)
106°
Avg peak temp
during heat waves
3
Dangerous nights 2026
Overnights ≥ 70°F
0
Heat waves 2026
so far

Days ≥ 90°F Per Year

1882–2026
46
2026 so far
46
Avg/year 1970–2025
54
Avg/year (last 10 complete)
80
Most in a year (1938)

Average Daily High by Decade

Full year · complete decades only

Longest Heat Waves — Lewiston

# Dates Days Peak Avg High Avg Overnight Low
🏆 Jun 26, 2021 – Jul 6, 2021 11 115°F (Jun 29) 105°F 71°F
2 Jul 13, 1938 – Jul 23, 1938 11 113°F (Jul 21) 108°F 65°F
3 Aug 14, 1897 – Aug 24, 1897 11 111°F (Aug 20) 106°F 60°F
4 Aug 10, 1967 – Aug 20, 1967 11 105°F (Aug 17) 102°F 64°F
5 Jun 26, 2015 – Jul 4, 2015 9 111°F (Jun 28) 104°F 70°F
6 Aug 2, 1942 – Aug 10, 1942 9 108°F (Aug 7) 105°F 62°F
7 Jul 27, 1973 – Aug 4, 1973 9 104°F (Aug 1) 102°F 65°F
8 Jul 22, 1939 – Jul 29, 1939 8 117°F (Jul 27) 108°F 68°F
9 Jul 14, 1941 – Jul 21, 1941 8 112°F (Jul 17) 105°F 68°F
10 Jul 7, 2024 – Jul 14, 2024 8 108°F (Jul 10) 104°F 68°F

Heat Waves Per Year

Warm Summer Nights (Jun–Aug)

Nights where the overnight low exceeded the 1991–2020 normal low

40
2026 total
above-normal nights
38.3
Avg / summer
1970–2020
67
Most in a summer
2021

Above-Normal Summer Nights Per Year

Average June–August Low by Decade

Overnight lows · complete decades only

Precipitation

Annual totals and trend across the full period of record · see this year's standing →

Monthly Precipitation — Last 24 Months

Blue = actual · dashed line = monthly normal

Annual Precipitation Per Year (1881–2026)

Blue = above average · tan = below average · gold = 2026 (partial)
Since 1881, annual totals have trended -0.11" per decade, about -1.7" across the record.

Heavy Rain Days Per Year (≥ 1.0")

Compare year-to-year changes in days with heavy rainfall (≥ 1.0")

This Year — 2026

How Lewiston is tracking against normal, year to date

Daily High Temperature vs Normal

Above normal Below normal

146 of 253 days with data were above the 1991–2020 normal high for their date.

Precipitation, Year to Date

9.91"
2026 YTD
Normal: 9.01"
+0.90"
0.82"
September so far
September normal: 0.60"
+0.22"
0
2026 heavy rain days
Days with ≥ 1.0"

Accumulation vs. Normal

Running total since Jan 1 against the normal pace for the same date · Lewiston is 0.90" ahead of the normal pace

Period Review — Aug 11 – Sep 10, 2026

Any window, evaluated against every other year on record — 31 days

Quick picks: Last 7 days Last 30 days Last 90 days This month
Seasons: Spring (Mar–May) Summer (Jun–Aug) Fall (Sep–Nov)
72.5°F
Average temperature
43rd-warmest of 133
+0.4°
vs. average
Normal: 72.1°F (1991–2020)

Average Temperature by Year — Aug 11 – Sep 10

1882–2026 · 2026 highlighted · trend +0.19° per decade (warming since 1882)

Precipitation by Year — Aug 11 – Sep 10

1882–2025 · 2026 highlighted · trend -0.01" per decade (drier since 1882)

Warmest Aug 11 – Sep 10 on Record

# Year Avg Temp
1 2025 79.0°F
2 1967 78.3°F
3 2022 78.1°F
4 2013 76.4°F
5 1923 76.2°F
6 2017 75.3°F
7 1981 75.2°F
8 1998 75.2°F
9 1940 75.2°F
10 2023 75.1°F

Coolest Aug 11 – Sep 10 on Record

# Year Avg Temp
1 1960 64.6°F
2 1912 64.7°F
3 1959 64.8°F
4 1964 65.1°F
5 1954 65.2°F
6 1910 65.7°F
7 1978 65.8°F
8 1899 66.2°F
9 2000 66.4°F
10 1907 66.8°F
About this data. Pick any start and end date and this becomes the same kind of review as the Month and Fall tabs, just for exactly the window you asked for — the generalized version of the same engine, evaluated across every year on record. Average temperature is the mean of each day's (high + low) / 2; precipitation is the sum of daily totals. A year missing more than about a fifth of the window's days is excluded from the temperature ranking; any missing day excludes a year from the precipitation ranking, since an unreported day is unreported rain. Ranges that cross from December into January aren't supported yet. Normals are the 1991–2020 mean for the same window.
← Back to all stations