Monthly outlook for Key Biscayne, FL: average high 83.3°, average low 77.5°. That is 0.9° above the climate normal for October. Precipitation is expected on 14 days (about 5.5 inches), against a normal of 8 days and 2.3 inches. The warmest day looks like 12 October (92.4°), the coolest 13 October (72.6°).
83.3°/77.5°
Average high / low
+0.9°
Above normal
14 / 8
Wet days / normal
5.5 in
Precipitation this month
Ten-day blocks vs climate normal
Period
Forecast high
Normal
Difference
11 October – 20 October
84.7°
82°
+1.5°
21 October – 30 October
81°
80.9°
+0.1°
31 October – 9 November
at normal
79.5°
—
October records over 66 years
91.8°13 October 2023All-time high
54.5°30 October 2017All-time low
Mon, 1292° / 79°0.13
92 °
Key Biscayne, Monday, 12 October
Light rain. High 92°, low 79°.
Pressure30.03 inHg
Wind4.5 mph NE
Humidity67%
Visibility6.2 mi
Dew point75°
Tue, 1386° / 73°0
86 °
Key Biscayne, Tuesday, 13 October
Clear. High 86°, low 73°.
Pressure30.00 inHg
Wind5.6 mph N
Humidity62%
Visibility6.2 mi
Dew point70°
Wed, 1486° / 74°0.08
86 °
Key Biscayne, Wednesday, 14 October
Light rain. High 86°, low 74°.
Pressure30.00 inHg
Wind7.8 mph NE
Humidity59%
Visibility6.2 mi
Dew point70°
Thu, 1587° / 77°0.26
87 °
Key Biscayne, Thursday, 15 October
Light rain. High 87°, low 77°.
Pressure30.00 inHg
Wind7.7 mph E
Humidity68%
Visibility—
Dew point74°
Fri, 1685° / 78°0.09
85 °
Key Biscayne, Friday, 16 October
Light rain. High 85°, low 78°.
Pressure29.97 inHg
Wind7.9 mph SE
Humidity71%
Visibility—
Dew point74°
Sat, 1783° / 78°0.92
83 °
Key Biscayne, Saturday, 17 October
Rain. High 83°, low 78°.
Pressure29.88 inHg
Wind11.2 mph E
Humidity82%
Visibility—
Dew point73°
Sun, 1877° / 75°2.33
77 °
Key Biscayne, Sunday, 18 October
Heavy rain. High 77°, low 75°.
Pressure29.97 inHg
Wind34.4 mph NE
Humidity85%
Visibility—
Dew point72°
Mon, 1979° / 76°0.23
79 °
Key Biscayne, Monday, 19 October
Light rain. High 79°, low 76°.
Pressure30.06 inHg
Wind33.2 mph NE
Humidity76%
Visibility—
Dew point70°
Tue, 2080° / 78°0.02
80 °
Key Biscayne, Tuesday, 20 October
Light rain. High 80°, low 78°.
Pressure30.03 inHg
Wind25.5 mph NE
Humidity68%
Visibility—
Dew point68°
Wed, 2181° / 78°0.06
81 °
Key Biscayne, Wednesday, 21 October
Light rain. High 81°, low 78°.
Pressure30.00 inHg
Wind22.9 mph NE
Humidity63%
Visibility—
Dew point66°
Thu, 2281° / 78°0.2
81 °
Key Biscayne, Thursday, 22 October
Light rain. High 81°, low 78°.
Pressure30.00 inHg
Wind19.5 mph NE
Humidity64%
Visibility—
Dew point67°
Fri, 2381° / 78°0.13
81 °
Key Biscayne, Friday, 23 October
Light rain. High 81°, low 78°.
Pressure30.00 inHg
Wind16.2 mph NE
Humidity60%
Visibility—
Dew point65°
Sat, 2481° / 77°0.46
81 °
Key Biscayne, Saturday, 24 October
Rain. High 81°, low 77°.
Pressure30.03 inHg
Wind16 mph NE
Humidity55%
Visibility—
Dew point63°
Sun, 2582° / 79°0.1
82 °
Key Biscayne, Sunday, 25 October
Light rain. High 82°, low 79°.
Pressure30.06 inHg
Wind21.9 mph E
Humidity55%
Visibility—
Dew point64°
Mon, 2680° / 78°0.4
80 °
Key Biscayne, Monday, 26 October
Rain. High 80°, low 78°.
Pressure30.09 inHg
Wind20.8 mph E
Humidity72%
Visibility—
Dew point70°
From day 17 onward the outlook is built from 60-year climate statistics
Tue, 2781° / 73°0.04
81 °
Key Biscayne, Tuesday, 27 October
Climate normal for this date — 60-year average.
Average high81°
Average low73°
Average precipitation0.04 in
Chance of precipitation28%
Record high85° (2021)
Record low63° (2005)
Wed, 2881° / 73°0.12
81 °
Key Biscayne, Wednesday, 28 October
Climate normal for this date — 60-year average.
Average high81°
Average low73°
Average precipitation0.12 in
Chance of precipitation35%
Record high86° (1972)
Record low60° (2008)
Thu, 2981° / 73°0.09
81 °
Key Biscayne, Thursday, 29 October
Climate normal for this date — 60-year average.
Average high81°
Average low73°
Average precipitation0.09 in
Chance of precipitation38%
Record high86° (2021)
Record low58° (2008)
Fri, 3080° / 73°0.1
80 °
Key Biscayne, Friday, 30 October
Climate normal for this date — 60-year average.
Average high80°
Average low73°
Average precipitation0.1 in
Chance of precipitation38%
Record high87° (2002)
Record low55° (2017)
Sat, 3180° / 73°0.1
80 °
Key Biscayne, Saturday, 31 October
Climate normal for this date — 60-year average.
Average high80°
Average low73°
Average precipitation0.1 in
Chance of precipitation43%
Record high88° (2023)
Record low59° (2017)
Sun, 0180° / 73°0.1
80 °
Key Biscayne, Sunday, 1 November
Climate normal for this date — 60-year average.
Average high80°
Average low73°
Average precipitation0.1 in
Chance of precipitation47%
Record high85° (2002)
Record low57° (1993)
Mon, 0280° / 73°0.12
80 °
Key Biscayne, Monday, 2 November
Climate normal for this date — 60-year average.
Average high80°
Average low73°
Average precipitation0.12 in
Chance of precipitation48%
Record high85° (1997)
Record low55° (2014)
Tue, 0380° / 73°0.14
80 °
Key Biscayne, Tuesday, 3 November
Climate normal for this date — 60-year average.
Average high80°
Average low73°
Average precipitation0.14 in
Chance of precipitation48%
Record high85° (2009)
Record low58° (1966)
Wed, 0480° / 72°0.13
80 °
Key Biscayne, Wednesday, 4 November
Climate normal for this date — 60-year average.
Average high80°
Average low72°
Average precipitation0.13 in
Chance of precipitation55%
Record high84° (2019)
Record low54° (1966)
Thu, 0579° / 72°0.16
79 °
Key Biscayne, Thursday, 5 November
Climate normal for this date — 60-year average.
Average high79°
Average low72°
Average precipitation0.16 in
Chance of precipitation43%
Record high85° (1992)
Record low56° (1969)
Fri, 0679° / 71°0.08
79 °
Key Biscayne, Friday, 6 November
Climate normal for this date — 60-year average.
Average high79°
Average low71°
Average precipitation0.08 in
Chance of precipitation35%
Record high89° (2002)
Record low56° (1969)
Sat, 0779° / 71°0.07
79 °
Key Biscayne, Saturday, 7 November
Climate normal for this date — 60-year average.
Average high79°
Average low71°
Average precipitation0.07 in
Chance of precipitation27%
Record high85° (2025)
Record low56° (2021)
Sun, 0879° / 71°0.11
79 °
Key Biscayne, Sunday, 8 November
Climate normal for this date — 60-year average.
Average high79°
Average low71°
Average precipitation0.11 in
Chance of precipitation38%
Record high85° (2025)
Record low60° (2021)
Mon, 0979° / 71°0.12
79 °
Key Biscayne, Monday, 9 November
Climate normal for this date — 60-year average.
Average high79°
Average low71°
Average precipitation0.12 in
Chance of precipitation32%
Record high85° (2025)
Record low61° (1997)
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 Key Biscayne, 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 Key Biscayne, 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.