Port Alcan, AK Climate: Temperature & Rain by Month
Explore NOAA NCEI's 1991–2020 climate normals → and a clearly labeled PlainClimate comfort calculation
30-year climate normals (1991-2020) from Port Alcan's primary NOAA station, PORT ALCAN.
The climate verdict for Port Alcan
Winter sets the terms in Port Alcan, Alaska. A pronounced 70°F seasonal swing and heating demand above twice the cooling total frame an annual average of 24°F. At 39/100 (below average) the climate comfort score falls in the bottom third of the station-mapped U.S. score corpus, exceeding only 4% of scores.
- 24°F
- annual average temperature (NOAA normal)
- 39/100
- comfort score, above 4% of station-mapped location scores
- 11.0"
- annual precipitation · 27" snow
- 93 days
- frost-free growing season
Port Alcan: NOAA 1991-2020 normals describe a typical year, not a forecast. Method: /methodology.
Normals record plate
Sheet USC00507513 · Port Alcan, AK 24°F mean · 11.0" precip
TEMP-COLD · RANK-COOL · PHOTO-FINISH · PRCP-ARID · SWING-WIDE · COMF-LOW · LOAD-HEAT · STN-1 · BOOK-FULL
- TEMP-COLD 24°F
- RANK-COOL #1
- PHOTO-FINISH ≈ Manley Hot Spri…
- PRCP-ARID 11.0"
- SWING-WIDE 70°F
- COMF-LOW 39/100
- LOAD-HEAT 14,873 HDD
- STN-1 USC00507513
- BOOK-FULL 6/6 fields
Nearest mean-temperature peer: Manley Hot Springs, AK (+ 0.6 °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 AK station list.
- Hot Tanana Calhoun…, AK 26°F
- Near Manley Hot Spri…, AK 25°F
- Near Northway, AK 25°F
- Port Alcan (this station) 24°F
- Cold Deering, AK 23°F
Port Alcan sits in Alaska, the #1 coldest U.S. state at 33.5°F statewide annual average - see all 50 coldest states ranked by NOAA normals
Climate Living Index · Port Alcan
Port Alcan: 7/100 · grade F
Port Alcan publishes 5 of 6 Living Index dimensions (NOAA annual/seasonal normals · NOAA daily multivariate normals); 1 missing weight rescale to 100.
PlainClimate-derived for Port Alcan, not an official NOAA rating. Rankings still use Comfort Score 39/100 (separate formula). Breakpoints and limits.
| Dimension | Station value | Score |
|---|---|---|
| Snowfall burden | 27.4 inches/year | 41/100 · D |
| Precipitation balance | 11.0 in · 24.0 from 35 in | 15/100 · F |
| Annual temperature balance | 24.1°F · 43.4° from 67.5°F | 0/100 · F |
| Frost-free season | 93 days/year | 0/100 · F |
| Normal heat + freeze calendar | 245 calendar days | 0/100 · F |
Port Alcan · 2026-08-04 · NOAA NCEI Climate Normals · method · Comfort Score method.
Port Alcan is a continental Köppen climate: Dsc
Coldest-month mean -12.1°F and warmest-month mean 57.9°F place this station in continental, dry-summer, cool summer climates (Dsc). Class Dsc is the Peel et al. (2007) label for this station's monthly mean temperature and precipitation normals: continental, specifically continental, dry-summer, cool summer.
- Köppen code
- Dsc
- Group
- Continental
- Warmest month
- 57.9°F
- Coldest month
- -12.1°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 Port Alcan sits across the climate record
Three NOAA fields for Port Alcan's primary station, temperature, precipitation, and seasonal swing, are ranked against every station-mapped normal that carries the same field.
- Annual temperature
- Cooler than 100%
- Among 6,861 stations, Port Alcan sits in the cooler third of annual means.
- Annual precipitation
- Drier than 92%
- Port Alcan's annual total ranks in the drier third of 6,352 measured normals.
- Seasonal temperature swing
- Wider than 99%
- Warmest-to-coldest month gap for Port Alcan is large versus 6,861 complete station-years.
How Port Alcan compares across U.S. station-mapped locations
Port Alcan's comfort score vs. all station-mapped locations
PlainClimate composite comfort index (1–100), NOAA 1991–2020 normals
39 4th percentile score exceeds 4% 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%). This entry sits in this band.
- 40–50: 1,113 station-mapped locations (18%). Above this entry.
- 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 | -5°F (-21°C) | -19°F (-28°C) | -12°F (-24°C) | 0.3" | 3.5" | 31.0 | 0.0 |
| February | 6°F (-14°C) | -13°F (-25°C) | -3°F (-20°C) | 0.3" | 2.9" | 28.0 | 0.0 |
| March | 23°F (-5°C) | -6°F (-21°C) | 8°F (-13°C) | 0.1" | 3.0" | 31.0 | 0.0 |
| April | 43°F (6°C) | 17°F (-8°C) | 30°F (-1°C) | 0.2" | 0.9" | 29.1 | 0.0 |
| May | 58°F (14°C) | 33°F (1°C) | 46°F (8°C) | 0.9" | 0.7" | 13.2 | 0.0 |
| June | 67°F (19°C) | 44°F (6°C) | 55°F (13°C) | 2.2" | 0.0" | 0.7 | 0.0 |
| July | 69°F (21°C) | 47°F (8°C) | 58°F (14°C) | 2.7" | 0.0" | 0.0 | 0.0 |
| August | 65°F (18°C) | 41°F (5°C) | 53°F (12°C) | 1.7" | 0.0" | 2.0 | 0.0 |
| September | 53°F (12°C) | 30°F (-1°C) | 42°F (5°C) | 1.0" | 0.5" | 18.7 | 0.0 |
| October | 31°F (-1°C) | 14°F (-10°C) | 23°F (-5°C) | 0.5" | 4.1" | 30.7 | 0.0 |
| November | 8°F (-14°C) | -7°F (-22°C) | 0°F (-18°C) | 0.7" | 7.1" | 30.0 | 0.0 |
| December | -2°F (-19°C) | -16°F (-27°C) | -9°F (-23°C) | 0.4" | 4.7" | 31.0 | 0.0 |
The year, day by day
Summer here tops out rather than builds: the warmest normal high is 70°F around July 7, short of 90°F on every date, while 245 dates carry a normal low at or below freezing, the coldest -20°F near January 10.
The freezing stretch
The normal low stays at or below 32°F into May 12, then returns to freezing around September 11, covering 245 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 June 26, when 43% of years recorded at least a hundredth of an inch. The driest is March 29 at 7%. Summed across the calendar, that is about 79 wet dates a year.
The widest day
March 21 carries the biggest normal gap between afternoon and dawn, 30°F between the normal high and the normal low.
Look up any date
Any date's 1991–2020 normal for Port Alcan.
Where Port Alcan Stands Nationally
Winters bite deep and often: the normal nightly low dips to freezing or below on around 245 nights a year, placing this among the most frost-prone tenth of ranked stations.
Aridity defines the water calendar: about 11 inches in a normal year lands this among the driest tenth of ranked stations.
Port Alcan earns 2 nationally notable standings (outer quintiles) against 6,860 NOAA 1991–2020 normals stations; only those extremes render.
Monthly Precipitation
Average monthly rainfall and snowfall
Snow: 3.5"
3.7 days with precipitation
Snow: 2.9"
3.1 days with precipitation
Snow: 3.0"
2.3 days with precipitation
Snow: 0.9"
2.4 days with precipitation
Snow: 0.7"
5.7 days with precipitation
12.5 days with precipitation
13.0 days with precipitation
11.0 days with precipitation
Snow: 0.5"
8.0 days with precipitation
Snow: 4.1"
5.4 days with precipitation
Snow: 7.1"
5.6 days with precipitation
Snow: 4.7"
4.6 days with precipitation
Port Alcan runs a summer-peaked wet season
61% of Port Alcan's yearly precipitation falls in June, July and August alone, against the 25% an evenly spread year would give those three months. The wettest month is July at 2.7", on a wide 70°F gap between its warmest and coldest month. Warm-season convection and, across the Southwest, the North American monsoon produce this shape: rain arrives in short heavy bursts during the hottest part of the year rather than as long cool-season soaking.
- Wettest three months: July, June, August, taking 61% of the annual total between them.
- Driest month: March at 0.1".
- Winter share: 8% falls in December, January and February.
Shares are computed from this station's own 1991-2020 monthly precipitation normals. A summer-peaked label means the June-August share reaches 35%; it describes timing across an average year, not any single season, and says nothing about how heavy an individual storm can be.
Port Alcan is dry, and what does fall arrives gently
Only about 77 days a year record measurable precipitation here, 21% of the calendar, and they carry 11.0" 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 July at about 13 wet days; the driest is March at about 2.
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 Port Alcan
Port Alcan averages 27.4 inches of snowfall a year, with November the snowiest month on the normals, spread across roughly 25 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: 27.4 inches of depth.
- Days recording measurable snow: about 25 a year.
- At a rough ten-to-one melt ratio, snow accounts for on the order of 25% 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
August 29
50% probability date
Last Spring Freeze
May 28
50% probability date
Growing Season
93 days
Heating & Cooling Degree Days
Annual totals indicate energy demand for heating and cooling
Heating Degree Days
14,873
Higher = more heating needed
Cooling Degree Days
10
Higher = more cooling needed
Warmest Month
July
Coldest Month
January
Nationwide similar cities
Other rankable U.S. places outside AK closest to Port Alcan 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 (24°F here).
- Cooke City, MT 34°F · 10.1°F off
- Crested Butte, CO 34°F · 10.1°F off
- Silver Gate, MT 34°F · 10.2°F off
- Stanley, ID 34°F · 10.3°F off
Closest by annual precipitation
Nearest out-of-state peers by annual precipitation (11.0" here), excluding temperature-peer places.
- Moro, OR 11.0" · 0.0" off
- Porterville, CA 11.0" · 0.0" off
- McNeal, AZ 11.0" · 0.0" off
- Snowflake, AZ 11.0" · 0.0" off
Snow and freeze rhythm
When cold and snow define Port Alcan
heating led · dry · high swing
Winter and seasonal range jointly define this record. Port Alcan logs 14,873 heating degree days, more than twice its 10 cooling total, while the typical coldest-to-warmest-month gap reaches 70.0°F. The annual mean therefore compresses two materially different seasons.
Only about 93 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. Port Alcan coldest normal
January
Averaging -12°F (-24°C), this month sits below freezing for the month as a whole, not merely overnight.
-
2. Port Alcan typical freeze period
January through December
The station reports average freezing days from January through December.
-
3. Port Alcan snow peak
November
Port Alcan averages 27.4 inches of snow a year, with November the snowiest month on the normals.
Questions about Port Alcan's climate
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Data Sources
Data source: NOAA U.S. Climate Normals v1.0.1 (1991-2020). All figures on this page are from Port Alcan's primary station: PORT ALCAN (USC00507513). For informational purposes only.
Place identity: U.S. Census Bureau 2024 Gazetteer places. The conservative exact name-and-state crosswalk finds no Census place match, so PlainClimate treats this as a station-mapped location and does not claim it is a municipality. No exact Gazetteer row for Port Alcan; facility counts that depend on place identity are therefore an upper bound, not a municipal census.
On this page every temperature, precipitation, and derived score for Port Alcan 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.