Monthly outlook for Marathon, FL: average high 83.7°, average low 80.8°. That is 1.6° above the climate normal for October. Precipitation is expected on 13 days (about 4.1 inches), against a normal of 7 days and 2.4 inches. The warmest day looks like 9 October (91.5°), the coolest 23 October (75.5°).
83.7°/80.8°
Average high / low
+1.6°
Above normal
13 / 7
Wet days / normal
4.1 in
Precipitation this month
Ten-day blocks vs climate normal
Period
Forecast high
Normal
Difference
8 October – 17 October
84.9°
81.2°
+2.1°
18 October – 27 October
81.7°
79.9°
+1°
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, 0992° / 83°0.09
92 °
Marathon, Friday, 9 October
Light rain. High 92°, low 83°.
Pressure29.94 inHg
Wind16 mph S
Humidity76%
Visibility6.2 mi
Dew point76°
Sat, 1085° / 81°0.18
85 °
Marathon, Saturday, 10 October
Rain. High 85°, low 81°.
Pressure30.03 inHg
Wind17.3 mph S
Humidity77%
Visibility6.2 mi
Dew point76°
Sun, 1185° / 83°0.09
85 °
Marathon, Sunday, 11 October
Light rain. High 85°, low 83°.
Pressure30.09 inHg
Wind11.3 mph SE
Humidity76%
Visibility6.2 mi
Dew point77°
Mon, 1284° / 82°0.07
84 °
Marathon, Monday, 12 October
Light rain. High 84°, low 82°.
Pressure30.03 inHg
Wind10.2 mph NE
Humidity84%
Visibility6.2 mi
Dew point78°
Tue, 1384° / 80°0.02
84 °
Marathon, Tuesday, 13 October
Light rain. High 84°, low 80°.
Pressure29.94 inHg
Wind13.6 mph NE
Humidity63%
Visibility—
Dew point68°
Wed, 1483° / 81°0.2
83 °
Marathon, Wednesday, 14 October
Light rain. High 83°, low 81°.
Pressure29.94 inHg
Wind18.1 mph E
Humidity71%
Visibility—
Dew point71°
Thu, 1583° / 82°0.15
83 °
Marathon, Thursday, 15 October
Light rain. High 83°, low 82°.
Pressure30.03 inHg
Wind20.8 mph E
Humidity76%
Visibility—
Dew point75°
Fri, 1683° / 83°0.03
83 °
Marathon, Friday, 16 October
Light rain. High 83°, low 83°.
Pressure30.00 inHg
Wind21.9 mph E
Humidity75%
Visibility—
Dew point74°
Sat, 1782° / 81°0.22
82 °
Marathon, Saturday, 17 October
Light rain. High 82°, low 81°.
Pressure29.91 inHg
Wind18.2 mph E
Humidity70%
Visibility—
Dew point71°
Sun, 1881° / 80°1.17
81 °
Marathon, Sunday, 18 October
Rain. High 81°, low 80°.
Pressure29.88 inHg
Wind23.1 mph NE
Humidity77%
Visibility—
Dew point73°
Mon, 1983° / 80°0.28
83 °
Marathon, Monday, 19 October
Light rain. High 83°, low 80°.
Pressure29.97 inHg
Wind28.9 mph E
Humidity69%
Visibility—
Dew point71°
Tue, 2081° / 80°0.69
81 °
Marathon, Tuesday, 20 October
Rain. High 81°, low 80°.
Pressure29.97 inHg
Wind29.4 mph E
Humidity76%
Visibility—
Dew point73°
Wed, 2182° / 81°0.1
82 °
Marathon, Wednesday, 21 October
Light rain. High 82°, low 81°.
Pressure29.94 inHg
Wind25.5 mph E
Humidity68%
Visibility—
Dew point70°
Thu, 2282° / 81°0.01
82 °
Marathon, Thursday, 22 October
Light rain. High 82°, low 81°.
Pressure29.91 inHg
Wind19.7 mph E
Humidity67%
Visibility—
Dew point70°
Fri, 2382° / 75°0.55
82 °
Marathon, Friday, 23 October
Rain. High 82°, low 75°.
Pressure29.91 inHg
Wind15.3 mph E
Humidity77%
Visibility—
Dew point70°
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.