American Falls, ID Climate: Temperature & Rain by Month
Annual temperature and rainfall from NOAA NCEI's 1991–2020 normals →; comfort score computed by PlainClimate
30-year climate normals (1991-2020) from American Falls's primary NOAA station, AMERICAN FALLS 6 NE - 2 stations mapped to the area.
The climate verdict for American Falls
Dryness leads the climate profile for American Falls, Idaho, with 11.1 inches of precipitation a year. NOAA records an annual average of 47°F. At 49/100 (moderate) the climate comfort score falls in the bottom third of the station-mapped U.S. score corpus, exceeding only 18% of scores.
- 47°F
- average temperature, NOAA 1991-2020 normal
- 49/100
- comfort score, above 18% of station-mapped location scores
- 11.1"
- annual precipitation · 35" snow
- 141 days
- growing season, frost-free days
American Falls: NOAA 1991-2020 normals describe a typical year, not a forecast. Method: /methodology.
Normals record plate
Sheet USC00100227 · American Falls, ID 47°F mean · 11.1" precip
TEMP-COOL · RANK-COOL · PHOTO-FINISH · PRCP-ARID · SWING-MID · COMF-LOW · LOAD-HEAT · STN-MULTI · BOOK-FULL
- TEMP-COOL 47°F
- RANK-COOL #1,784
- PHOTO-FINISH ≈ Bennington Mors…
- PRCP-ARID 11.1"
- SWING-MID 44°F
- COMF-LOW 49/100
- LOAD-HEAT 6,997 HDD
- STN-MULTI USC00100227
- BOOK-FULL 6/6 fields
Nearest mean-temperature peer: Bennington Morse St, VT (+ 0 °F mean)
Instrument codes from this station's NOAA 1991–2020 normals, mean temperature, corpus warmth rank, photo-finish peer station, precipitation band, seasonal swing, comfort composite, degree-day load, and field book, not a livability rating.
Mean-temperature neighbourhood
Nationwide NOAA normal poles and nearest peers, not a reprint of every ID station list.
- American Falls (this station) 47°F
- Cold Philipsburg, PA 47°F
- Hot Whitney Point D…, NY 47°F
- Near Bennington Mors…, VT 47°F
- Near Francis E Walte…, PA 47°F
Climate Living Index · American Falls
American Falls: 28/100 · grade F
American Falls publishes 5 of 6 Living Index dimensions (NOAA annual/seasonal normals · NOAA daily multivariate normals); 1 missing weight rescale to 100.
PlainClimate-derived for American Falls, not an official NOAA rating. Rankings still use Comfort Score 49/100 (separate formula). Breakpoints and limits.
| Dimension | Station value | Score |
|---|---|---|
| Normal heat + freeze calendar | 161 calendar days | 39/100 · F |
| Snowfall burden | 34.9 inches/year | 33/100 · F |
| Annual temperature balance | 46.7°F · 20.8° from 67.5°F | 26/100 · F |
| Frost-free season | 141 days/year | 19/100 · F |
| Precipitation balance | 11.1 in · 23.9 from 35 in | 15/100 · F |
American Falls · 2026-08-04 · NOAA NCEI Climate Normals · method · Comfort Score method.
American Falls's normals sit in a dry climate class: BSk
Precipitation is low relative to temperature but above true desert thresholds: cold semi-arid steppe (BSk). Class BSk is the Peel et al. (2007) label for this station's monthly mean temperature and precipitation normals: dry (arid or semi-arid), specifically cold semi-arid steppe.
- Köppen code
- BSk
- Group
- Dry (arid or semi-arid)
- Warmest month
- 69.0°F
- Coldest month
- 24.6°F
Source: official public datasets monthly normals (1991–2020) at the city’s primary station. This is a station classification, not a mapped regional consensus.
National standing · heating-led station
Where American Falls sits across the climate record
Three NOAA fields for American Falls's primary station, temperature, precipitation, and seasonal swing, are ranked against every station-mapped normal that carries the same field.
- Annual temperature
- Cooler than 74%
- Among 6,861 stations, American Falls sits in the cooler third of annual means.
- Annual precipitation
- Drier than 92%
- American Falls's annual total ranks in the drier third of 6,352 measured normals.
- Seasonal temperature swing
- 55th percentile swing
- Typical seasonal amplitude versus 6,861 complete station-years.
How American Falls compares across U.S. station-mapped locations
American Falls's comfort score vs. all station-mapped locations
PlainClimate composite comfort index (1–100), NOAA 1991–2020 normals
49 18th percentile score exceeds 18% of 6,189 station-mapped location scores
- 0–10: 0 station-mapped locations (0%). Below this entry.
- 10–20: 0 station-mapped locations (0%). Below this entry.
- 20–30: 96 station-mapped locations (2%). Below this entry.
- 30–40: 280 station-mapped locations (5%). Below this entry.
- 40–50: 1,113 station-mapped locations (18%). This entry sits in this band.
- 50–60: 1,329 station-mapped locations (21%). Above this entry.
- 60–70: 1,236 station-mapped locations (20%). Above this entry.
- 70–80: 650 station-mapped locations (11%). Above this entry.
- 80–90: 921 station-mapped locations (15%). Above this entry.
- 90–100: 564 station-mapped locations (9%). Above this entry.
Source NOAA U.S. Climate Normals, PlainClimate comfort index · 1991–2020
Monthly Temperatures
Average daily high and low temperatures by month
| Month | Avg High | Avg Low | Mean | Precip | Snow | Freeze Days | 90°F+ Days |
|---|---|---|---|---|---|---|---|
| January | 32°F (0°C) | 17°F (-8°C) | 25°F (-4°C) | 1.3" | 9.4" | 29.7 | 0.0 |
| February | 37°F (3°C) | 20°F (-6°C) | 29°F (-2°C) | 0.9" | 7.2" | 25.2 | 0.0 |
| March | 50°F (10°C) | 28°F (-2°C) | 39°F (4°C) | 1.1" | 3.2" | 22.1 | 0.0 |
| April | 59°F (15°C) | 34°F (1°C) | 46°F (8°C) | 1.2" | 2.5" | 12.4 | 0.0 |
| May | 68°F (20°C) | 41°F (5°C) | 55°F (13°C) | 1.3" | 0.5" | 2.9 | 0.2 |
| June | 76°F (24°C) | 47°F (8°C) | 62°F (16°C) | 0.8" | 0.0" | 0.2 | 1.5 |
| July | 85°F (29°C) | 54°F (12°C) | 69°F (21°C) | 0.3" | 0.0" | 0.0 | 10.3 |
| August | 85°F (29°C) | 53°F (12°C) | 69°F (21°C) | 0.5" | 0.0" | 0.0 | 10.9 |
| September | 75°F (24°C) | 45°F (7°C) | 60°F (15°C) | 0.8" | 0.1" | 1.1 | 0.9 |
| October | 60°F (16°C) | 36°F (2°C) | 48°F (9°C) | 0.8" | 1.1" | 10.8 | 0.0 |
| November | 45°F (7°C) | 26°F (-4°C) | 35°F (2°C) | 0.8" | 3.0" | 22.3 | 0.0 |
| December | 33°F (0°C) | 18°F (-8°C) | 25°F (-4°C) | 1.2" | 7.9" | 28.7 | 0.0 |
The year, day by day
Summer here tops out rather than builds: the warmest normal high is 87°F around July 29, short of 90°F on every date, while 161 dates carry a normal low at or below freezing, the coldest 17°F near January 1.
The freezing stretch
The normal low stays at or below 32°F into April 6, then returns to freezing around October 29, covering 161 dates in all.
Derived from the normal daily minimum. This is a different measure from the 50%-probability frost dates shown elsewhere on this page, which come from NOAA’s frost product.
Where the wet dates fall
The likeliest wet date is January 4, when 33% of years recorded at least a hundredth of an inch. The driest is July 15 at 9%. Summed across the calendar, that is about 79 wet dates a year.
The widest day
August 19 carries the biggest normal gap between afternoon and dawn, 32°F between the normal high and the normal low.
Look up any date
Any date's 1991–2020 normal for American Falls.
Where American Falls Stands Nationally
Aridity defines the water calendar: about 11 inches in a normal year lands this among the driest tenth of ranked stations.
American Falls earns one nationally notable standing (outer quintile) against 6,860 NOAA 1991–2020 normals stations, middle-of-the-pack metrics stay silent here.
Monthly Precipitation
Average monthly rainfall and snowfall
Snow: 9.4"
10.4 days with precipitation
Snow: 7.2"
8.2 days with precipitation
Snow: 3.2"
7.6 days with precipitation
Snow: 2.5"
7.6 days with precipitation
Snow: 0.5"
7.2 days with precipitation
5.2 days with precipitation
2.7 days with precipitation
3.6 days with precipitation
Snow: 0.1"
4.2 days with precipitation
Snow: 1.1"
5.5 days with precipitation
Snow: 3.0"
7.3 days with precipitation
Snow: 7.9"
9.5 days with precipitation
American Falls spreads its precipitation across the year
Neither half of the year dominates here: June through August take 14% of the annual total and December through February 31%, with neither reaching the 35% that would mark a distinct wet season. American Falls has no dry season to plan around, though it does carry a 44.4°F seasonal spread.
The gap between the wettest and driest month still matters: May averages 1.3" and July 0.3". The three wettest months together take 35% of the year, against the 25% a perfectly flat distribution would give them.
Shares are computed from this station's own 1991-2020 monthly precipitation normals. "Spread across the year" means neither the June-August nor the December-February share reaches 35%; it describes an average year, not the variability of any single one.
American Falls is dry, and what does fall arrives gently
Only about 79 days a year record measurable precipitation here, 22% of the calendar, and they carry 11.1" between them. At roughly 0.14 inches on an average wet day, this is not the damp drizzle of a marine climate; it is an arid record in which precipitation is both uncommon and light when it appears.
The wettest month by count is January at about 10 wet days; the driest is July at about 3.
A low per-event average in a dry record is a statement about typical days only. Arid regions can still take a large share of a year's total from a single convective storm, which a normal cannot show.
A wet day is one recording at least 0.01 inches. These are 1991-2020 normals: they describe an average year, not the extremes within it.
Winter brings real snow to American Falls
American Falls averages 34.9 inches of snowfall a year, with January the snowiest month on the normals, spread across roughly 28 days that record measurable snow. That is depth accumulating on the ground, which is why it can exceed the annual precipitation figure: precipitation counts the liquid the snow melts down to, and fresh snow is mostly air.
- Annual snowfall: 34.9 inches of depth.
- Days recording measurable snow: about 28 a year.
- At a rough ten-to-one melt ratio, snow accounts for on the order of 32% of the year's precipitation.
NOAA 1991-2020 normals. The ten-to-one ratio is a convention, not a measurement: real ratios vary with temperature, so treat the share as an order of magnitude rather than an exact split.
Frost Dates & Growing Season
First Fall Freeze
October 2
50% probability date
Last Spring Freeze
May 14
50% probability date
Growing Season
141 days
Heating & Cooling Degree Days
Annual totals indicate energy demand for heating and cooling
Heating Degree Days
6,997
Higher = more heating needed
Cooling Degree Days
363
Higher = more cooling needed
Warmest Month
July
Coldest Month
January
Nationwide similar cities
Other rankable U.S. places outside ID closest to American Falls on two NOAA annual-normal axes (mean temperature and annual precipitation). Chip rows use distinct link sets.
Closest by average temperature
Nearest out-of-state peers by annual mean temperature (47°F here).
- Allison, IA 47°F · 0.0°F off
- Cherokee, IA 47°F · 0.0°F off
- Forsyth, MT 47°F · 0.0°F off
- Fort Duchesne, UT 47°F · 0.0°F off
Closest by annual precipitation
Nearest out-of-state peers by annual precipitation (11.1" here), excluding temperature-peer places.
- Coulee Dam, WA 11.1" · 0.0" off
- Odessa, WA 11.1" · 0.0" off
- Alcalde, NM 11.1" · 0.0" off
- Snowflake, AZ 11.0" · 0.0" off
Snow and freeze rhythm
When cold and snow define American Falls
heating led · dry · mid swing
American Falls's energy balance leans toward cold weather: 6,997 annual heating degree days against 363 for cooling. Its 44.4°F seasonal range still makes the monthly rows more useful than the annual average alone.
Only about 141 days are frost-free in a normal year. That short interval is consistent with the cold-season signal, but the measure does not predict the exact first or last freeze in any one year.
-
1. American Falls coldest normal
January
Averaging 25°F (-4°C), this month sits below freezing for the month as a whole, not merely overnight.
-
2. American Falls typical freeze period
January through December
The station reports average freezing days from January through December.
-
3. American Falls snow peak
January
American Falls averages 34.9 inches of snow a year, with January the snowiest month on the normals.
Questions about American Falls's climate
How much snow does American Falls get? ▼
How cold does American Falls get in winter? ▼
How much energy does heating and cooling require in American Falls? ▼
Data Sources
Data source: NOAA U.S. Climate Normals v1.0.1 (1991-2020). All figures on this page are from American Falls's primary station: AMERICAN FALLS 6 NE (USC00100227). 2 NOAA stations are mapped to the American Falls area; the primary station's record is used for consistency. For informational purposes only.
Place identity: U.S. Census Bureau 2024 Gazetteer places. The 2024 Census Gazetteer identifies the exact name-and-state match as an incorporated place (GEOID 1601900). Match rule for American Falls: exact normalized name + state only, no fuzzy expansion, so nearby differently spelled facilities stay unmatched.
On this page every temperature, precipitation, and derived score for American Falls comes from its primary NOAA station record. No figure on this page is typed in by an editor - each value is rendered from NOAA 1991-2020 U.S. Climate Normals. See our editorial standards & corrections policy, the methodology behind these numbers, or report a data error. Data current as of 1991–2020 normals.