PlainClimate
NOAA 1991–2020 normals Station-mapped location · no exact Census place match 1 NOAA station · Primary-station record

Saint Johns, AZ 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 Saint Johns's primary NOAA station, SAINT JOHNS.

The climate verdict for Saint Johns

Dryness leads the climate profile for Saint Johns, Arizona, with 9.4 inches of precipitation a year. NOAA records an annual average of 55°F. At 44/100 (moderate) the climate comfort score falls in the bottom third of the station-mapped U.S. score corpus, exceeding only 10% of scores.

55°F
average temperature, NOAA 1991-2020 normal
44/100
comfort score, above 10% of station-mapped location scores
9.4"
annual precipitation · 6" snow
165 days
frost-free days per growing season

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

Normals record plate

Sheet USC00027435 · Saint Johns, AZ 55°F mean · 9.4" precip

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

Nearest mean-temperature peer: Free Union, VA (+ 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 AZ station list.

Climate Living Index · Saint Johns

Saint Johns: 36/100 · grade F

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

F
36/100Climate Living Index

PlainClimate-derived for Saint Johns, not an official NOAA rating. Rankings still use Comfort Score 44/100 (separate formula). Breakpoints and limits.

Saint Johns Living Index dimension scores
DimensionStation valueScore
Snowfall burden 6.2 inches/year 69/100 · C
Annual temperature balance 54.7°F · 12.8° from 67.5°F 58/100 · C
Frost-free season 165 days/year 38/100 · F
Normal heat + freeze calendar 196 calendar days 16/100 · F
Precipitation balance 9.4 in · 25.6 from 35 in 10/100 · F

Saint Johns · 2026-08-04 · NOAA NCEI Climate Normals · method · Comfort Score method.

Saint Johns'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
75.3°F
Coldest month
34.5°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 Saint Johns sits across the climate record

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

Annual temperature
59th percentile warmth
Mid-pack annual mean versus 6,861 station normals.
Annual precipitation
Drier than 95%
Saint Johns's annual total ranks in the drier third of 6,352 measured normals.
Seasonal temperature swing
39th percentile swing
Typical seasonal amplitude versus 6,861 complete station-years.

How Saint Johns compares across U.S. station-mapped locations

Saint Johns's comfort score vs. all station-mapped locations

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

44 10th percentile score exceeds 10% 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.

Saint Johns's measured station temperature trend

Methodology

Across 72 complete annual observations from 1915 to 2025, SAINT JOHNS warmed at a fitted rate of 0.07°C per decade. The line shows the fitted change relative to its first year, not raw year-to-year temperatures or a forecast.

Saint Johns fitted annual mean temperature change, 1915-2025 Fitted station-temperature change from 1915 to 2025, relative to the fitted first year. The linear trend warmed at 0.07 °C per decade. -0.2°C +0.0°C +0.2°C +0.4°C +0.6°C +0.8°C 192019401960198020002020
  • Saint Johns primary station fitted change +0.07 °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 50°F (10°C) 21°F (-6°C) 35°F (2°C)
February 56°F (13°C) 24°F (-5°C) 40°F (4°C)
March 64°F (18°C) 29°F (-2°C) 46°F (8°C)
April 71°F (22°C) 35°F (2°C) 53°F (12°C)
May 80°F (27°C) 44°F (7°C) 62°F (17°C)
June 90°F (32°C) 52°F (11°C) 71°F (22°C)
July 91°F (33°C) 60°F (15°C) 75°F (24°C)
August 88°F (31°C) 58°F (14°C) 73°F (23°C)
September 83°F (28°C) 51°F (10°C) 67°F (19°C)
October 73°F (23°C) 38°F (3°C) 55°F (13°C)
November 60°F (16°C) 27°F (-3°C) 44°F (7°C)
December 49°F (10°C) 20°F (-7°C) 35°F (1°C)

The year, day by day

Saint Johns works both ends of the calendar. Normal highs climb to 92°F by June 28 and hold at or above 90°F on 43 dates, then normal lows drop to freezing or below on 153 dates, bottoming at 19°F around December 20.

Normal daily high and low temperature for Saint Johns, January through December Peaks 92°F around June 28. Bottoms 19°F around December 20. 10 30 50 70 90 freezing JanFebMarAprMayJunJulAugSepOctNovDec
Normal daily high and low across the calendar year. NOAA 1991–2020 daily normals, SAINT JOHNS.

When the heat sits

Normal highs reach 90°F from June 14 through July 26, covering 43 dates. The broader mild season, normal highs of 70°F or more, runs April 12 to October 22.

This counts calendar dates whose 1991–2020 normal high reaches 90°F. It is a smaller number than the 90°F+ day counts in the monthly table above, which measure how often the threshold was actually crossed in a typical year. A date can average 88°F and still exceed 90°F in half of all years.

The freezing stretch

The normal low stays at or below 32°F into April 3, then returns to freezing around November 3, covering 153 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 August 1, when 26% of years recorded at least a hundredth of an inch. The driest is June 4 at 4%. Summed across the calendar, that is about 37 wet dates a year.

The widest day

June 11 carries the biggest normal gap between afternoon and dawn, 39°F between the normal high and the normal low.

Look up any date

Any date's 1991–2020 normal for Saint Johns.

Where Saint Johns Stands Nationally

Aridity defines the water calendar: about 9 inches in a normal year lands this among the driest tenth of ranked stations.

Day-to-night contrast is extreme by national standards — the widest normal daily swing reaches about 39°F, sharper than nine in ten ranked stations see.

Saint Johns 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

January 0.6"

Snow: 1.2"

2.9 days with precipitation

February 0.6"

Snow: 0.7"

2.6 days with precipitation

March 0.3"

Snow: 0.2"

1.9 days with precipitation

April 0.3"

Snow: 0.1"

1.6 days with precipitation

May 0.4"

Snow: 0.1"

1.9 days with precipitation

June 0.2"

1.3 days with precipitation

July 1.9"

6.7 days with precipitation

August 1.9"

7.4 days with precipitation

September 1.1"

3.3 days with precipitation

October 0.9"

Snow: 0.5"

2.6 days with precipitation

November 0.6"

Snow: 0.9"

2.1 days with precipitation

December 0.7"

Snow: 2.5"

2.4 days with precipitation

Saint Johns runs a summer-peaked wet season

44% of Saint Johns'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 August at 1.9", on a 40.8°F seasonal spread. 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.

How Saint Johns's precipitation splits across the calendar

About 37 days a year record measurable precipitation here, carrying 9.4" between them, or roughly 0.26 inches on a typical wet day. That sits in the middle band: neither the many-light-days pattern of the Pacific Northwest and the Great Lakes, nor the few-heavy-events pattern of the Gulf and the desert Southwest.

Wet days a year
37
Wettest month by days
August
Driest month by days
June

A wet day is one recording at least 0.01 inches. These are 1991-2020 normals: they describe an average year and say nothing about the heaviest single storm on record.

Snow reaches Saint Johns, but rarely amounts to much

The normals record 6.2 inches of snow a year here, most likely in December. That is a real but marginal amount: enough that snow is part of the local record, not enough to define the winter.

A figure in this range usually reflects a handful of events that melt quickly rather than a season of accumulation; about 3 days a year record any measurable snow at all.

NOAA 1991-2020 normals. An average across thirty years can smooth away a single heavy winter, so a small annual figure does not mean a significant snowfall is impossible.

Frost Dates & Growing Season

First Fall Freeze

October 14

50% probability date

Last Spring Freeze

May 2

50% probability date

Growing Season

165 days

Heating & Cooling Degree Days

Annual totals indicate energy demand for heating and cooling

Heating Degree Days

4,638

Higher = more heating needed

Cooling Degree Days

890

Higher = more cooling needed

Warmest Month

July

Coldest Month

December

Nationwide similar cities

Other rankable U.S. places outside AZ closest to Saint Johns 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 (55°F here).

Closest by annual precipitation

Nearest out-of-state peers by annual precipitation (9.4" here), excluding temperature-peer places.

Arizona climate overview →

Scarce-water calendar

Where Saint Johns's limited precipitation lands

heating led · dry · mid swing

Saint Johns's energy balance leans toward cold weather: 4,638 annual heating degree days against 890 for cooling. Its 40.8°F seasonal range still makes the monthly rows more useful than the annual average alone.

Saint Johns's frost-free season lasts about 165 days, a middle-length window whose endpoints matter more than the annual average. It describes freeze probability, not year-specific planting conditions.

July and December mark the typical warm and cold ends of the calendar in Saint Johns's middle-range seasonal profile. The measured spread is 40.8°F. The annual average is 55°F. Neither the annual mean nor one extreme month represents the full calendar on its own.

Saint Johns's cold-season load does not imply a wet climate. Annual precipitation is 9.4 inches, which places the station in PlainClimate's dry range. Annual snowfall totals 6.2 inches. The snowfall and rainfall fields should be read separately rather than inferred from temperature.

Saint Johns wettest normal

August

August concentrates the scarce annual total (9.4 inches).

Saint Johns driest normal

June

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

Questions about Saint Johns's climate

How dry is Saint Johns?
Saint Johns receives 9.4 inches of precipitation a year, spread across roughly 37 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 many days above 90°F does Saint Johns get?
Saint Johns averages about 51 days a year at or above 90°F, concentrated in July and the months either side of it. That is a count of days reaching the threshold, not a measure of how far above it they go.
How much energy does heating and cooling require in Saint Johns?
Saint Johns has 4,638 heating degree days and 890 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 Saint Johns's primary station: SAINT JOHNS (USC00027435). 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 Saint Johns; facility counts that depend on place identity are therefore an upper bound, not a municipal census.

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 Saint Johns 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.