PlainClimate
NOAA 1991–2020 normals Census-designated place · exact match 1 NOAA station · Primary-station record

Big Delta, AK Climate: Temperature & Rain by Month

Temperature and precipitation from NOAA NCEI 1991–2020 normals →, plus PlainClimate's derived comfort score

30-year climate normals (1991-2020) from Big Delta's primary NOAA station, BIG DELTA AP.

The climate verdict for Big Delta

Winter sets the terms in Big Delta, Alaska. A pronounced 61.7°F seasonal swing and heating demand above twice the cooling total frame an annual average of 30°F. At 40/100 (moderate) the climate comfort score falls in the bottom third of the station-mapped U.S. score corpus, exceeding only 6% of scores.

30°F
yearly average temperature, NOAA normal
40/100
comfort score, above 6% of station-mapped location scores
10.3"
annual precipitation
113 days
frost-free days per growing season

Big Delta: NOAA 1991-2020 normals describe a typical year, not a forecast. Method: /methodology.

Normals record plate

Sheet USW00026415 · Big Delta, AK 30°F mean · 10.3" precip

TEMP-COLD · RANK-COOL · PHOTO-FINISH · PRCP-ARID · SWING-WIDE · COMF-LOW · LOAD-HEAT · STN-1 · BOOK-FULL

Nearest mean-temperature peer: Two Rivers, AK ( -0.1 °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.

Big Delta 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 · Big Delta

Big Delta: 14/100 · grade F

Big Delta publishes 5 of 6 Living Index dimensions (NOAA annual/seasonal normals · NOAA daily multivariate normals · NOAA hourly normals); 1 missing weight rescale to 100.

F
14/100Climate Living Index

PlainClimate-derived for Big Delta, not an official NOAA rating. Rankings still use Comfort Score 40/100 (separate formula). Breakpoints and limits.

Big Delta Living Index dimension scores
DimensionStation valueScore
Summer moisture balance 43.9°F mean dew point 55/100 · C
Precipitation balance 10.3 in · 24.7 from 35 in 13/100 · F
Normal heat + freeze calendar 215 calendar days 7/100 · F
Frost-free season 113 days/year 4/100 · F
Annual temperature balance 30.0°F · 37.5° from 67.5°F 0/100 · F

Big Delta · 2026-08-04 · NOAA NCEI Climate Normals · method · Comfort Score method.

Big Delta is a continental Köppen climate: Dwc

Coldest-month mean -1.0°F and warmest-month mean 60.7°F place this station in continental, dry-winter, cool summer climates (Dwc). Class Dwc is the Peel et al. (2007) label for this station's monthly mean temperature and precipitation normals: continental, specifically continental, dry-winter, cool summer.

Köppen code
Dwc
Group
Continental
Warmest month
60.7°F
Coldest month
-1.0°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 Big Delta sits across the climate record

Three NOAA fields for Big Delta's primary station, temperature, precipitation, and seasonal swing, are ranked against every station-mapped normal that carries the same field.

Annual temperature
Cooler than 99%
Among 6,861 stations, Big Delta sits in the cooler third of annual means.
Annual precipitation
Drier than 93%
Big Delta'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 Big Delta is large versus 6,861 complete station-years.

How Big Delta compares across U.S. station-mapped locations

Big Delta's comfort score vs. all station-mapped locations

PlainClimate composite comfort index (1–100), NOAA 1991–2020 normals

40 6th percentile score exceeds 6% 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. This location 0 100 every station-mapped location, bucketed by value
  1. 0–10: 0 station-mapped locations (0%). Below this entry.
  2. 10–20: 0 station-mapped locations (0%). Below this entry.
  3. 20–30: 96 station-mapped locations (2%). Below this entry.
  4. 30–40: 280 station-mapped locations (5%). Below this entry.
  5. 40–50: 1,113 station-mapped locations (18%). This entry sits in this band.
  6. 50–60: 1,329 station-mapped locations (21%). Above this entry.
  7. 60–70: 1,236 station-mapped locations (20%). Above this entry.
  8. 70–80: 650 station-mapped locations (11%). Above this entry.
  9. 80–90: 921 station-mapped locations (15%). Above this entry.
  10. 90–100: 564 station-mapped locations (9%). Above this entry.

Source NOAA U.S. Climate Normals, PlainClimate comfort index · 1991–2020

Each bar is a band; taller bars hold more station-mapped locations. The dashed line + filled bar mark this entry. Hover or tap any bar for its full count, share, and where it sits relative to this entry.

Big Delta's measured station temperature trend

Methodology

Across 75 complete annual observations from 1943 to 2025, BIG DELTA AP warmed at a fitted rate of 0.36°C per decade. The line shows the fitted change relative to its first year, not raw year-to-year temperatures or a forecast.

Big Delta fitted annual mean temperature change, 1943-2025 Fitted station-temperature change from 1943 to 2025, relative to the fitted first year. The linear trend warmed at 0.36 °C per decade. -0.5°C +0.0°C +0.5°C +1.0°C +1.5°C +2.0°C +2.5°C +3.0°C 1960198020002020
  • Big Delta primary station fitted change +0.36 °C/decade
Source: NOAA GHCN-M v4, quality-controlled monthly mean temperature. PlainClimate fits ordinary least squares over complete calendar years; minimum 30 years, record must reach 2015 or later.

Monthly Temperatures

Average daily high and low temperatures by month

Month Avg High Avg Low Mean
January 6°F (-14°C) -8°F (-22°C) -1°F (-18°C)
February 16°F (-9°C) -1°F (-18°C) 7°F (-14°C)
March 25°F (-4°C) 4°F (-16°C) 14°F (-10°C)
April 44°F (7°C) 24°F (-5°C) 34°F (1°C)
May 59°F (15°C) 38°F (3°C) 49°F (9°C)
June 68°F (20°C) 49°F (9°C) 59°F (15°C)
July 70°F (21°C) 52°F (11°C) 61°F (16°C)
August 65°F (18°C) 47°F (8°C) 56°F (13°C)
September 53°F (12°C) 36°F (2°C) 45°F (7°C)
October 33°F (1°C) 20°F (-7°C) 27°F (-3°C)
November 15°F (-9°C) 1°F (-17°C) 8°F (-13°C)
December 9°F (-13°C) -5°F (-20°C) 2°F (-16°C)

The year, day by day

Summer here tops out rather than builds: the warmest normal high is 71°F around June 30, short of 90°F on every date, while 215 dates carry a normal low at or below freezing, the coldest -9°F near January 9.

Normal daily high and low temperature for Big Delta, January through December Peaks 71°F around June 30. Bottoms -9°F around January 9. -20 0 20 40 60 80 freezing JanFebMarAprMayJunJulAugSepOctNovDec
Normal daily high and low across the calendar year. NOAA 1991–2020 daily normals, BIG DELTA AP.

The freezing stretch

The normal low stays at or below 32°F into April 28, then returns to freezing around September 27, covering 215 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 July 2, when 45% of years recorded at least a hundredth of an inch. The driest is March 30 at 11%. Summed across the calendar, that is about 95 wet dates a year.

The widest day

March 23 carries the biggest normal gap between afternoon and dawn, 22°F between the normal high and the normal low.

Look up any date

Any date's 1991–2020 normal for Big Delta.

Where Big Delta Stands Nationally

Winters bite deep and often: the normal nightly low dips to freezing or below on around 215 nights a year, placing this among the most frost-prone tenth of ranked stations.

Aridity defines the water calendar: about 10 inches in a normal year lands this among the driest tenth of ranked stations.

Big Delta earns 2 nationally notable standings (outer quintiles) against 6,860 NOAA 1991–2020 normals stations; only those extremes render.

Monthly Precipitation

Average monthly rainfall

January 0.2"

5.9 days with precipitation

February 0.2"

5.1 days with precipitation

March 0.2"

3.7 days with precipitation

April 0.2"

3.7 days with precipitation

May 0.8"

7.9 days with precipitation

June 2.2"

12.9 days with precipitation

July 2.4"

14.0 days with precipitation

August 2.0"

12.8 days with precipitation

September 0.9"

8.5 days with precipitation

October 0.6"

7.8 days with precipitation

November 0.4"

7.4 days with precipitation

December 0.2"

6.3 days with precipitation

Big Delta runs a summer-peaked wet season

64% of Big Delta'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 2.4", on a wide 61.7°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.

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.

Big Delta is dry, and what does fall arrives gently

Only about 96 days a year record measurable precipitation here, 26% of the calendar, and they carry 10.3" between them. At roughly 0.11 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 14 wet days; the driest is March at about 4.

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.

Frost Dates & Growing Season

First Fall Freeze

September 7

50% probability date

Last Spring Freeze

May 17

50% probability date

Growing Season

113 days

Heating & Cooling Degree Days

Annual totals indicate energy demand for heating and cooling

Heating Degree Days

12,783

Higher = more heating needed

Cooling Degree Days

34

Higher = more cooling needed

Warmest Month

July

Coldest Month

January

Humidity & Wind

Monthly averages from hourly observations

Month Humidity Wind (mph)
January 73% 11.8
February 66% 10.0
March 56% 9.2
April 48% 8.5
May 49% 8.0
June 59% 6.7
July 64% 7.1
August 66% 7.3
September 69% 8.5
October 78% 10.0
November 75% 11.8
December 76% 12.2

Nationwide similar cities

Other rankable U.S. places outside AK closest to Big Delta 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 (30°F here).

Closest by annual precipitation

Nearest out-of-state peers by annual precipitation (10.3" here), excluding temperature-peer places.

Alaska climate overview →

Scarce-water calendar

Where Big Delta's limited precipitation lands

heating led · dry · high swing

Winter and seasonal range jointly define this record. Big Delta logs 12,783 heating degree days, more than twice its 34 cooling total, while the typical coldest-to-warmest-month gap reaches 61.7°F. The annual mean therefore compresses two materially different seasons.

Only about 113 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.

July and January mark the typical warm and cold ends of the calendar in this dry, high-range record. The gap is 61.7°F, so a single annual figure is especially lossy; the annual average is 30°f. Compare monthly temperature and precipitation together before drawing a seasonal conclusion about Big Delta.

Big Delta's cold-season load does not imply a wet climate. Annual precipitation is 10.3 inches, which places the station in PlainClimate's dry range. Snowfall is not added to the interpretation because its annual value is missing. The snowfall and rainfall fields should be read separately rather than inferred from temperature.

Big Delta wettest normal

July

July concentrates the scarce annual total (10.3 inches).

Big Delta driest normal

March

March is typically driest; arid stations are defined by when water is absent, not by a four-season grid.

Questions about Big Delta's climate

How dry is Big Delta?
Big Delta receives 10.3 inches of precipitation a year, spread across roughly 96 days that record any measurable amount. For reference, the contiguous United States averages near 30 inches. Based on NOAA 30-year climate normals (1991-2020).
How cold does Big Delta get in winter?
Big Delta records about 219 days a year with a low at or below freezing, with January the coldest month on the normals, and an annual average daily low of 21°F.
How much energy does heating and cooling require in Big Delta?
Big Delta has 12,783 heating degree days and 34 cooling degree days annually, a heating-dominated climate. Degree-day definitions: reading weather data.

Data Sources

Data source: NOAA U.S. Climate Normals v1.0.1 (1991-2020). All figures on this page are from Big Delta's primary station: BIG DELTA AP (USW00026415). 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 a census-designated place (GEOID 0206850), not an incorporated municipality. Match rule for Big Delta: exact normalized name + state only, no fuzzy expansion, so nearby differently spelled facilities stay unmatched.

Data sourced from official public datasets. See our methodology for details. Retrieved and formatted by PlainClimate

On this page every temperature, precipitation, and derived score for Big Delta 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.