Helena, OK 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 Helena's primary NOAA station, HELENA 1 SSE.
The climate verdict for Helena
Helena, Oklahoma has a mixed annual climate rather than one dominant extreme. Its NOAA normal shows an annual average of 59°F. It scores 78/100 for climate comfort (good), putting it in the top third of station-mapped location scores and exceeding 72% of them.
- 59°F
- yearly average temperature, NOAA normal
- 78/100
- comfort score, above 72% of station-mapped location scores
- 32.1"
- annual precipitation · 13" snow
- 205 days
- frost-free growing season
Helena: NOAA 1991-2020 normals describe a typical year, not a forecast. Method: /methodology.
Normals record plate
Sheet USC00344019 · Helena, OK 59°F mean · 32.1" precip
TEMP-MILD · RANK-UPPER · PHOTO-FINISH · PRCP-MID · SWING-WIDE · COMF-TOP · LOAD-HEAT · STN-1 · BOOK-FULL
- TEMP-MILD 59°F
- RANK-UPPER #4,871
- PHOTO-FINISH ≈ Medford
- PRCP-MID 32.1"
- SWING-WIDE 48°F
- COMF-TOP 78/100
- LOAD-HEAT 4,162 HDD
- STN-1 USC00344019
- BOOK-FULL 6/6 fields
Nearest mean-temperature peer: Medford, OK ( -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 OK station list.
- Helena (this station) 59°F
- Cold Alva, OK 59°F
- Hot Waynoka, OK 59°F
- Near Medford, OK 59°F
- Near Hennessey, OK 59°F
Climate Living Index · Helena
Helena: 59/100 · grade C
Helena publishes 5 of 6 Living Index dimensions (NOAA annual/seasonal normals · NOAA daily multivariate normals); 1 missing weight rescale to 100.
PlainClimate-derived for Helena, not an official NOAA rating. Rankings still use Comfort Score 78/100 (separate formula). Breakpoints and limits.
| Dimension | Station value | Score |
|---|---|---|
| Precipitation balance | 32.1 in · 2.9 from 35 in | 89/100 · A |
| Annual temperature balance | 58.8°F · 8.7° from 67.5°F | 72/100 · B |
| Frost-free season | 205 days/year | 68/100 · C |
| Snowfall burden | 12.7 inches/year | 59/100 · C |
| Normal heat + freeze calendar | 180 calendar days | 25/100 · F |
Helena · 2026-08-04 · NOAA NCEI Climate Normals · method · Comfort Score method.
Helena is a temperate Köppen climate: Cfa
Coldest-month mean 35.1°F and warmest-month mean 82.7°F place this station in temperate, no dry season, hot summer climates (Cfa). Class Cfa is the Peel et al. (2007) label for this station's monthly mean temperature and precipitation normals: temperate, specifically temperate, no dry season, hot summer.
- Köppen code
- Cfa
- Group
- Temperate
- Warmest month
- 82.7°F
- Coldest month
- 35.1°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 Helena sits across the climate record
Three NOAA fields for Helena's primary station, temperature, precipitation, and seasonal swing, are ranked against every station-mapped normal that carries the same field.
- Annual temperature
- Top 29% warmest
- Among 6,861 stations, Helena sits in the warmer third of annual means.
- Annual precipitation
- 43rd percentile wetness
- Neither arid nor torrential versus 6,352 station totals.
- Seasonal temperature swing
- Wider than 71%
- Warmest-to-coldest month gap for Helena is large versus 6,861 complete station-years.
How Helena compares across U.S. station-mapped locations
Helena's comfort score vs. all station-mapped locations
PlainClimate composite comfort index (1–100), NOAA 1991–2020 normals
78 Top 28% score exceeds 72% 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%). Below this entry.
- 50–60: 1,329 station-mapped locations (21%). Below this entry.
- 60–70: 1,236 station-mapped locations (20%). Below this entry.
- 70–80: 650 station-mapped locations (11%). This entry sits in this band.
- 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
Helena's measured station temperature trend
MethodologyAcross 58 complete annual observations from 1963 to 2025, HELENA 1 SSE warmed at a fitted rate of 0.11°C per decade. The line shows the fitted change relative to its first year, not raw year-to-year temperatures or a forecast.
- Helena primary station fitted change +0.11 °C/decade
Monthly Temperatures
Average daily high and low temperatures by month
| Month | Avg High | Avg Low | Mean | Precip | Snow | Freeze Days | 90°F+ Days |
|---|---|---|---|---|---|---|---|
| January | 47°F (8°C) | 23°F (-5°C) | 35°F (2°C) | 1.0" | 3.1" | 27.4 | 0.0 |
| February | 51°F (11°C) | 27°F (-3°C) | 39°F (4°C) | 1.3" | 2.4" | 21.8 | 0.0 |
| March | 61°F (16°C) | 36°F (2°C) | 48°F (9°C) | 2.2" | 3.2" | 12.0 | 0.0 |
| April | 70°F (21°C) | 44°F (7°C) | 57°F (14°C) | 3.3" | 0.0" | 3.5 | 0.6 |
| May | 80°F (26°C) | 56°F (13°C) | 68°F (20°C) | 4.4" | 0.0" | 0.1 | 4.7 |
| June | 90°F (32°C) | 66°F (19°C) | 78°F (25°C) | 4.4" | 0.0" | 0.0 | 16.6 |
| July | 95°F (35°C) | 70°F (21°C) | 83°F (28°C) | 3.2" | 0.0" | 0.0 | 25.1 |
| August | 93°F (34°C) | 69°F (20°C) | 81°F (27°C) | 3.7" | 0.0" | 0.0 | 21.8 |
| September | 85°F (30°C) | 61°F (16°C) | 73°F (23°C) | 2.6" | 0.0" | 0.0 | 10.8 |
| October | 73°F (23°C) | 48°F (9°C) | 60°F (16°C) | 3.0" | 0.2" | 1.7 | 1.6 |
| November | 59°F (15°C) | 35°F (2°C) | 47°F (8°C) | 1.6" | 0.4" | 13.4 | 0.0 |
| December | 48°F (9°C) | 26°F (-3°C) | 37°F (3°C) | 1.4" | 3.4" | 25.2 | 0.0 |
The year, day by day
Helena works both ends of the calendar. Normal highs climb to 96°F by July 20 and hold at or above 90°F on 77 dates, then normal lows drop to freezing or below on 103 dates, bottoming at 23°F around January 12.
When the heat sits
Normal highs reach 90°F from June 16 through August 31, covering 77 dates. The broader mild season, normal highs of 70°F or more, runs April 15 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 March 5, then returns to freezing around November 24, covering 103 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 May 24, when 30% of years recorded at least a hundredth of an inch. The driest is January 8 at 13%. Summed across the calendar, that is about 76 wet dates a year.
The widest day
April 1 carries the biggest normal gap between afternoon and dawn, 27°F between the normal high and the normal low.
Look up any date
Any date's 1991–2020 normal for Helena.
Where Helena Stands Nationally
Heat is a defining feature of the normals calendar — the normal daily high reaches 90°F on roughly 77 days a year, more than four out of five ranked stations record.
Helena 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: 3.1"
3.9 days with precipitation
Snow: 2.4"
4.8 days with precipitation
Snow: 3.2"
6.3 days with precipitation
7.5 days with precipitation
9.2 days with precipitation
8.1 days with precipitation
6.5 days with precipitation
8.0 days with precipitation
6.1 days with precipitation
Snow: 0.2"
6.2 days with precipitation
Snow: 0.4"
4.6 days with precipitation
Snow: 3.4"
4.8 days with precipitation
Helena runs a summer-peaked wet season
35% of Helena'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 June at 4.4", on a wide 47.6°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: June, May, August, taking 39% of the annual total between them.
- Driest month: January at 1.0".
- Winter share: 12% 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.
When it rains in Helena, it arrives in quantity
32.1" of precipitation falls across only about 76 wet days here, averaging 0.42 inches each. Fewer days carry more water: the year's total is delivered in comparatively heavy events rather than persistent damp.
- Days with measurable precipitation
- about 76 a year, 21% of all days
- Average depth per wet day
- 0.42 inches
- Most wet days
- May, about 9
- Fewest wet days
- January, about 4
A wet day is one recording at least 0.01 inches. These are 1991-2020 normals: they describe an average year, and a per-day average is not a forecast of any individual storm.
Winter brings real snow to Helena
Helena averages 12.7 inches of snowfall a year, with December the snowiest month on the normals, spread across roughly 6 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: 12.7 inches of depth.
- Days recording measurable snow: about 6 a year.
- At a rough ten-to-one melt ratio, snow accounts for on the order of 4% 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 31
50% probability date
Last Spring Freeze
April 9
50% probability date
Growing Season
205 days
Heating & Cooling Degree Days
Annual totals indicate energy demand for heating and cooling
Heating Degree Days
4,162
Higher = more heating needed
Cooling Degree Days
1,932
Higher = more cooling needed
Warmest Month
July
Coldest Month
January
Nationwide similar cities
Other rankable U.S. places outside OK closest to Helena 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 (59°F here).
- Athens, TN 59°F · 0.0°F off
- Clovis, NM 59°F · 0.0°F off
- Murray, KY 59°F · 0.0°F off
- Paducah, KY 59°F · 0.0°F off
Closest by annual precipitation
Nearest out-of-state peers by annual precipitation (32.1" here), excluding temperature-peer places.
- Lampasas, TX 32.2" · 0.0" off
- Mapleton, IA 32.2" · 0.0" off
- Battle Creek, IA 32.1" · 0.1" off
- Goodrich, MI 32.2" · 0.1" off
Snow and freeze rhythm
When cold and snow define Helena
heating led · moderate · mid swing
Helena's energy balance leans toward cold weather: 4,162 annual heating degree days against 1,932 for cooling. Its 47.6°F seasonal range still makes the monthly rows more useful than the annual average alone.
Helena's frost-free season lasts about 205 days, a middle-length window whose endpoints matter more than the annual average. It describes freeze probability, not year-specific planting conditions.
-
1. Helena coldest normal
January
The monthly mean of 35°F (2°C) sits near freezing, so cold nights and above-freezing afternoons share the same month.
-
2. Helena typical freeze period
January through December
The station reports average freezing days from January through December.
-
3. Helena snow peak
December
Helena averages 12.7 inches of snow a year, with December the snowiest month on the normals.
Questions about Helena's climate
How much snow does Helena get? ▼
How many days above 90°F does Helena get? ▼
How much energy does heating and cooling require in Helena? ▼
Data Sources
Data source: NOAA U.S. Climate Normals v1.0.1 (1991-2020). All figures on this page are from Helena's primary station: HELENA 1 SSE (USC00344019). 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 4033450). Match rule for Helena: 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 Helena 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.