Monthly outlook for Marathon, FL: average high 83.8°, average low 81.5°. That is 1.7° above the climate normal for October. Precipitation is expected on 11 days (about 2.1 inches), against a normal of 7 days and 2.4 inches. The warmest day looks like 8 October (87.3°), the coolest 8 October (79.8°).
83.8°/81.5°
Average high / low
+1.7°
Above normal
11 / 7
Wet days / normal
2.1 in
Precipitation this month
Ten-day blocks vs climate normal
Period
Forecast high
Normal
Difference
8 October – 17 October
84.5°
81.2°
+1.8°
18 October – 27 October
82.6°
79.9°
+1.5°
28 October – 6 November
at normal
78.8°
—
October records over 66 years
87.1°8 October 2024All-time high
63.9°21 October 1989All-time low
Climate normals and records are computed from the nearest reference point — Key Colony Beach (1 mi).
Fri, 0986° / 82°0.09
86 °
Marathon, Friday, 9 October
Light rain. High 86°, low 82°.
Pressure29.97 inHg
Wind14.6 mph SE
Humidity75%
Visibility4.4 mi
Dew point76°
Sat, 1085° / 81°0.11
85 °
Marathon, Saturday, 10 October
Rain. High 85°, low 81°.
Pressure30.03 inHg
Wind15.9 mph S
Humidity79%
Visibility6.2 mi
Dew point77°
Sun, 1185° / 80°0.08
85 °
Marathon, Sunday, 11 October
Light rain. High 85°, low 80°.
Pressure30.09 inHg
Wind11.4 mph E
Humidity76%
Visibility6.2 mi
Dew point77°
Mon, 1284° / 82°0.07
84 °
Marathon, Monday, 12 October
Light rain. High 84°, low 82°.
Pressure30.00 inHg
Wind13.8 mph NE
Humidity81%
Visibility—
Dew point77°
Tue, 1385° / 82°0
85 °
Marathon, Tuesday, 13 October
Clear. High 85°, low 82°.
Pressure29.94 inHg
Wind14.3 mph NE
Humidity57%
Visibility—
Dew point67°
Wed, 1483° / 82°0
83 °
Marathon, Wednesday, 14 October
Clear. High 83°, low 82°.
Pressure29.94 inHg
Wind15.3 mph E
Humidity59%
Visibility—
Dew point67°
Thu, 1583° / 82°0
83 °
Marathon, Thursday, 15 October
Clear. High 83°, low 82°.
Pressure30.00 inHg
Wind21.1 mph E
Humidity66%
Visibility—
Dew point69°
Fri, 1683° / 82°0.23
83 °
Marathon, Friday, 16 October
Light rain. High 83°, low 82°.
Pressure29.94 inHg
Wind24.1 mph E
Humidity76%
Visibility—
Dew point75°
Sat, 1784° / 83°0.61
84 °
Marathon, Saturday, 17 October
Rain. High 84°, low 83°.
Pressure29.91 inHg
Wind23.5 mph E
Humidity76%
Visibility—
Dew point75°
Sun, 1883° / 82°0.33
83 °
Marathon, Sunday, 18 October
Light rain. High 83°, low 82°.
Pressure29.97 inHg
Wind30.1 mph E
Humidity76%
Visibility—
Dew point74°
Mon, 1983° / 82°0.23
83 °
Marathon, Monday, 19 October
Light rain. High 83°, low 82°.
Pressure29.97 inHg
Wind31.2 mph E
Humidity76%
Visibility—
Dew point74°
Tue, 2083° / 81°0.01
83 °
Marathon, Tuesday, 20 October
Light rain. High 83°, low 81°.
Pressure29.97 inHg
Wind26.7 mph E
Humidity64%
Visibility—
Dew point69°
Wed, 2182° / 82°0.08
82 °
Marathon, Wednesday, 21 October
Light rain. High 82°, low 82°.
Pressure29.94 inHg
Wind18.9 mph E
Humidity69%
Visibility—
Dew point71°
Thu, 2282° / 81°0.07
82 °
Marathon, Thursday, 22 October
Light rain. High 82°, low 81°.
Pressure29.91 inHg
Wind19.5 mph E
Humidity71%
Visibility—
Dew point72°
Fri, 2382° / 82°0
82 °
Marathon, Friday, 23 October
Mostly clear. High 82°, low 82°.
Pressure29.94 inHg
Wind16.8 mph E
Humidity68%
Visibility—
Dew point71°
From day 17 onward the outlook is built from 60-year climate statistics
Sat, 2480° / 77°0.16
80 °
Marathon, Saturday, 24 October
Climate normal for this date — 60-year average.
Average high80°
Average low77°
Average precipitation0.16 in
Chance of precipitation42%
Record high84° (2019)
Record low71° (1982)
Sun, 2580° / 77°0.1
80 °
Marathon, Sunday, 25 October
Climate normal for this date — 60-year average.
Average high80°
Average low77°
Average precipitation0.1 in
Chance of precipitation30%
Record high83° (2019)
Record low67° (2005)
Mon, 2679° / 76°0.14
79 °
Marathon, Monday, 26 October
Climate normal for this date — 60-year average.
Average high79°
Average low76°
Average precipitation0.14 in
Chance of precipitation30%
Record high84° (2019)
Record low66° (2005)
Tue, 2780° / 76°0.09
80 °
Marathon, Tuesday, 27 October
Climate normal for this date — 60-year average.
Average high80°
Average low76°
Average precipitation0.09 in
Chance of precipitation35%
Record high84° (2019)
Record low70° (2005)
Wed, 2880° / 76°0.08
80 °
Marathon, Wednesday, 28 October
Climate normal for this date — 60-year average.
Average high80°
Average low76°
Average precipitation0.08 in
Chance of precipitation32%
Record high85° (2021)
Record low65° (2008)
Thu, 2979° / 76°0.08
79 °
Marathon, Thursday, 29 October
Climate normal for this date — 60-year average.
Average high79°
Average low76°
Average precipitation0.08 in
Chance of precipitation38%
Record high84° (2019)
Record low64° (2008)
Fri, 3079° / 76°0.04
79 °
Marathon, Friday, 30 October
Climate normal for this date — 60-year average.
Average high79°
Average low76°
Average precipitation0.04 in
Chance of precipitation30%
Record high83° (1993)
Record low67° (2017)
Sat, 3179° / 76°0.08
79 °
Marathon, Saturday, 31 October
Climate normal for this date — 60-year average.
Average high79°
Average low76°
Average precipitation0.08 in
Chance of precipitation38%
Record high83° (2020)
Record low70° (2017)
Sun, 0179° / 76°0.08
79 °
Marathon, Sunday, 1 November
Climate normal for this date — 60-year average.
Average high79°
Average low76°
Average precipitation0.08 in
Chance of precipitation37%
Record high84° (2019)
Record low63° (1993)
Mon, 0279° / 76°0.09
79 °
Marathon, Monday, 2 November
Climate normal for this date — 60-year average.
Average high79°
Average low76°
Average precipitation0.09 in
Chance of precipitation38%
Record high83° (2019)
Record low62° (2014)
Tue, 0379° / 75°0.08
79 °
Marathon, Tuesday, 3 November
Climate normal for this date — 60-year average.
Average high79°
Average low75°
Average precipitation0.08 in
Chance of precipitation43%
Record high83° (2019)
Record low67° (1966)
Wed, 0479° / 75°0.13
79 °
Marathon, Wednesday, 4 November
Climate normal for this date — 60-year average.
Average high79°
Average low75°
Average precipitation0.13 in
Chance of precipitation40%
Record high83° (2019)
Record low60° (1966)
Thu, 0578° / 75°0.1
78 °
Marathon, Thursday, 5 November
Climate normal for this date — 60-year average.
Average high78°
Average low75°
Average precipitation0.1 in
Chance of precipitation33%
Record high83° (2019)
Record low63° (1969)
Fri, 0678° / 75°0.06
78 °
Marathon, Friday, 6 November
Climate normal for this date — 60-year average.
Average high78°
Average low75°
Average precipitation0.06 in
Chance of precipitation25%
Record high83° (2019)
Record low64° (1969)
About the monthly outlook
How accurate is a 30-day forecast?
The first 16 days come from weather models — reliable for the first 3–5 days and progressively less so after that. Days 17 through 30 for Marathon, FL are built from the climate normal, the 60-year average, so they show typical weather for those dates rather than a specific forecast.
What does "above normal" mean?
We compare the forecast against the climate normal for those exact calendar days, computed from 60 years of observations. The deviation shows how much the coming month differs from a typical one.
Where do the 66-year records come from?
They are real temperature extremes recorded in Marathon, FL since 1960: the highest and lowest reading for each calendar date, with the year it happened.
How often is it updated?
The forecast portion refreshes every hour; the climate portion is based on long-term data and stays stable.