Marathon, FL 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 Marathon's primary NOAA station, MARATHON AP.
The climate verdict for Marathon
Warm-season cooling demand defines Marathon, Florida, running at more than twice its heating total. The NOAA normal records an annual average of 79°F. August is the warmest month at 86°F and January the coldest at 70°F.
- 79°F
- yearly average temperature, NOAA normal
- 39.7"
- annual precipitation
Marathon: NOAA 1991-2020 normals describe a typical year, not a forecast. Method: /methodology.
Normals record plate
Sheet USW00012896 · Marathon, FL 79°F mean · 39.7" precip
TEMP-HOT · RANK-WARM · PHOTO-FINISH · PRCP-MID · SWING-NARROW · COMF-UNK · LOAD-COOL · STN-1 · BOOK-FULL
- TEMP-HOT 79°F
- RANK-WARM #6,792
- PHOTO-FINISH ≈ Kailua Kona Ke-…
- PRCP-MID 39.7"
- SWING-NARROW 16°F
- COMF-UNK Comfort n/a
- LOAD-COOL 5,128 CDD
- STN-1 USW00012896
- BOOK-FULL 5/6 fields
Nearest mean-temperature peer: Kailua Kona Ke-ahole, HI ( -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 FL station list.
- Marathon (this station) 79°F
- Cold Curry Hammock S…, FL 78°F
- Near Kailua Kona Ke-…, HI 78°F
- Near Islamorada, FL 78°F
- Near Tavernier, FL 78°F
Marathon sits in Florida, the #1 hottest U.S. state at 72.6°F statewide annual average - see all 50 hottest states ranked by NOAA normals
Climate Living Index · Marathon
Marathon: 73/100 · grade B
Marathon publishes 3 of 6 Living Index dimensions (NOAA annual/seasonal normals · NOAA daily multivariate normals); 3 missing weights rescale to 100.
PlainClimate-derived for Marathon, not an official NOAA rating. Breakpoints and limits.
| Dimension | Station value | Score |
|---|---|---|
| Precipitation balance | 39.7 in · 4.7 from 35 in | 83/100 · B |
| Normal heat + freeze calendar | 101 calendar days | 75/100 · B |
| Annual temperature balance | 78.8°F · 11.3° from 67.5°F | 64/100 · C |
Marathon · 2026-08-04 · NOAA NCEI Climate Normals · method .
Marathon stays in the tropical Köppen band: Aw
Year-round heat with a pronounced dry season: tropical savanna (Aw). Class Aw is the Peel et al. (2007) label for this station's monthly mean temperature and precipitation normals: tropical, specifically tropical savanna.
- Köppen code
- Aw
- Group
- Tropical
- Warmest month
- 85.6°F
- Coldest month
- 70.0°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 · cooling-led station
Where Marathon sits across the climate record
Three NOAA fields for Marathon's primary station, temperature, precipitation, and seasonal swing, are ranked against every station-mapped normal that carries the same field.
- Annual temperature
- Top 1% warmest
- Among 6,861 stations, Marathon sits in the warmer third of annual means.
- Annual precipitation
- 57th percentile wetness
- Neither arid nor torrential versus 6,352 station totals.
- Seasonal temperature swing
- Narrower than 98%
- Warmest-to-coldest month gap for Marathon is compact versus 6,861 complete station-years.
Monthly Temperatures
Average daily high and low temperatures by month
| Month | Avg High | Avg Low | Mean | Precip | Freeze Days | 90°F+ Days |
|---|---|---|---|---|---|---|
| January | 76°F (24°C) | 64°F (18°C) | 70°F (21°C) | 1.6" | 0.0 | 0.0 |
| February | 78°F (26°C) | 66°F (19°C) | 72°F (22°C) | 1.7" | 0.0 | 0.0 |
| March | 81°F (27°C) | 69°F (20°C) | 75°F (24°C) | 1.3" | 0.0 | 0.0 |
| April | 84°F (29°C) | 73°F (23°C) | 78°F (26°C) | 2.1" | 0.0 | 1.9 |
| May | 88°F (31°C) | 76°F (24°C) | 82°F (28°C) | 3.4" | 0.0 | 7.4 |
| June | 90°F (32°C) | 79°F (26°C) | 84°F (29°C) | 4.2" | 0.0 | 19.0 |
| July | 91°F (33°C) | 79°F (26°C) | 85°F (30°C) | 3.8" | 0.0 | 25.5 |
| August | 92°F (33°C) | 80°F (27°C) | 86°F (30°C) | 5.3" | 0.0 | 27.4 |
| September | 90°F (32°C) | 78°F (26°C) | 84°F (29°C) | 6.4" | 0.0 | 19.0 |
| October | 86°F (30°C) | 76°F (24°C) | 81°F (27°C) | 5.9" | 0.0 | 4.6 |
| November | 81°F (27°C) | 71°F (22°C) | 76°F (24°C) | 1.8" | 0.0 | 0.0 |
| December | 78°F (26°C) | 68°F (20°C) | 73°F (23°C) | 2.2" | 0.0 | 0.0 |
The year, day by day
The year in Marathon runs from a mild 64°F around January 13 to 92°F at the peak near August 9, and the normal low never reaches freezing on any date in the record.
When the heat sits
Normal highs reach 90°F from June 7 through September 15, covering 101 dates. The broader mild season, normal highs of 70°F or more, runs January 1 to December 31.
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.
No freezing date
Not one calendar date in the 1991–2020 record carries a normal low at or below 32°F. The coldest normal low of the year is 64°F around January 13.
Where the wet dates fall
The likeliest wet date is September 9, when 51% of years recorded at least a hundredth of an inch. The driest is April 9 at 17%. Summed across the calendar, that is about 112 wet dates a year.
The widest day
March 14 carries the biggest normal gap between afternoon and dawn, 12°F between the normal high and the normal low.
Look up any date
Any date's 1991–2020 normal for Marathon.
Where Marathon Stands Nationally
Summers here run among the most heat-heavy normals calendars in the country: on about 101 days a year the normal daily high itself reaches 90°F — a count fewer than one station in ten exceeds.
Among the steadiest day-night climates ranked: even the widest normal daily swing holds to roughly 12°F.
Marathon earns 2 nationally notable standings (outer quintiles) against 6,860 NOAA 1991–2020 normals stations; only those extremes render.
Monthly Precipitation
Average monthly rainfall
7.9 days with precipitation
6.0 days with precipitation
5.8 days with precipitation
5.0 days with precipitation
7.9 days with precipitation
10.4 days with precipitation
12.5 days with precipitation
14.3 days with precipitation
15.1 days with precipitation
11.7 days with precipitation
7.1 days with precipitation
8.3 days with precipitation
Marathon spreads its precipitation across the year
Neither half of the year dominates here: June through August take 34% of the annual total and December through February 14%, with neither reaching the 35% that would mark a distinct wet season. Marathon has no dry season to plan around, though it does carry an unusually narrow 15.6°F seasonal spread.
The gap between the wettest and driest month still matters: September averages 6.4" and March 1.3". The three wettest months together take 44% 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.
When it rains in Marathon, it arrives in quantity
39.7" of precipitation falls across only about 112 wet days here, averaging 0.35 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 112 a year, 31% of all days
- Average depth per wet day
- 0.35 inches
- Most wet days
- September, about 15
- Fewest wet days
- April, about 5
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.
Frost Dates & Growing Season
First Fall Freeze
N/A
50% probability date
Last Spring Freeze
N/A
50% probability date
Heating & Cooling Degree Days
Annual totals indicate energy demand for heating and cooling
Heating Degree Days
71
Higher = more heating needed
Cooling Degree Days
5,128
Higher = more cooling needed
Warmest Month
August
Coldest Month
January
Nationwide similar cities
Other rankable U.S. places outside FL closest to Marathon 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 (79°F here).
- Kahului, HI 77°F · 1.7°F off
- Lihue, HI 76°F · 2.5°F off
- Brownsville, TX 76°F · 2.6°F off
- Needles, CA 76°F · 2.6°F off
Closest by annual precipitation
Nearest out-of-state peers by annual precipitation (39.7" here), excluding temperature-peer places.
- Bartlesville, OK 39.7" · 0.0" off
- Keosauqua, IA 39.7" · 0.0" off
- Spickard, MO 39.7" · 0.0" off
- Wellsville, NY 39.7" · 0.0" off
Data-derived climate profile
How Marathon's climate pattern fits together
cooling led · moderate · low swing
Warm-season load persists through a relatively even calendar in Marathon. Cooling totals 5,128 degree days, more than double the 71 heating measure, and the 15.6°F seasonal range is compact rather than sharply divided.
Marathon's 39.7 inches of annual precipitation falls in PlainClimate's middle band, so “wet” or “dry” is not the leading description. Snowfall is not added to the interpretation because its annual value is missing. Temperature balance and the calendar distribution carry more information than the annual moisture label alone.
Temperature varies within a narrow 15.6°F band across the normal year. August and January mark the typical warm and cold ends of the calendar. The annual average is 79°F. Monthly rows still matter, but they refine a steady profile rather than reveal two climatic extremes.
A frost-free growing-season length is not available for Marathon. That missing field is kept separate from the observed temperature and precipitation record rather than filled from a regional estimate.
These labels group NOAA 1991-2020 normals from Marathon's primary station, so the summer figures are a thirty-year average rather than a ceiling: individual years have run hotter and will again. For Marathon that means a descriptive range only — not an official NOAA classification and not a prediction for next summer.
Questions about Marathon's climate
How much rain does Marathon get? ▼
How many days above 90°F does Marathon get? ▼
How much energy does heating and cooling require in Marathon? ▼
Data Sources
Data source: NOAA U.S. Climate Normals v1.0.1 (1991-2020). All figures on this page are from Marathon's primary station: MARATHON AP (USW00012896). 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 1243000). Match rule for Marathon: 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 Marathon 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.