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Key Biscayne, Florida Weather

Midyear heat — the wet season grip. Day 15 of summer. Read this microseason across nine climate regions →

Key Biscayne weather forecast — hour by hour, 7-day outlook, NOAA radar

Key Biscayne, FL
Sunday, July 5 at 8:25 AM
82
°
Overcast
Feels like
86°
Humidity
87%
Wind
18 mph
Sunrise
2:34 AM
Sunset
4:15 PM
Key Biscayne, FL
Hour by hour · 24h
24-Hour ForecastKey Biscayne, FL: 24-hour forecast. Temperatures range from 78 to 85 degrees Fahrenheit with a 45% chance of precipitation at 7 AM.
L 78°H 85°
Key Biscayne, FL
7-day forecast
  1. Today
    Jul 5
    Heavy Showers
    34%
    1.4″
    86°78°—
  2. Monday
    Jul 6
    Heavy Showers
    45%
    0.59″
    86°79°0°
  3. Tuesday
    Jul 7
    Thunderstorm
    19%
    —
    89°83°+3°
  4. Wednesday
    Jul 8
    Light Showers
    —
    —
    90°84°+1°
  5. Thursday
    Jul 9
    Light Drizzle
    —
    —
    89°86°-1°
  6. Friday
    Jul 10
    Thunderstorm
    20%
    —
    89°85°0°
  7. Saturday
    Jul 11
    Overcast
    22%
    —
    90°86°+1°
Key Biscayne, FL
Next 24 hours · Warm now
76°82°88°6a12p6p12anow 81°high 85°low 78°PRECIP %
Key Biscayne, FL
Anemometer · 24h winds · from true
NESW
From · True
W
264° · veering 71°
Direction
W
264°
Sustained
18
mph
Gust
18
mph
Peak 24h
18
avg 9
Beaufort · 4 · MOD BRZ
0
CALM
<1
1
LIGHT AIR
1–3
2
LIGHT BRZ
4–7
3
GENTLE BRZ
8–12
4
MOD BRZ
13–18
5
FRESH BRZ
19–24
6
STRONG BRZ
25–31
7
NEAR GALE
32–38
24h · sust vs gust · mph
avg 9 · pk 18
0102030MPHB1B2B3B4B5B6B7-21h-18h-15h-12h-9h-6h-3h-24hNOWpk 2924SUSTGUST
−24h−18h−12h−6hnow
A fresh breeze drives the w-bound air across the harbor.
Key Biscayne, FL
Barometer · 24h pressure · mb
STORMRAINCHANGEFAIRDRY9901000101010201030
Pressure · mb
1017.3
+0.7 mb in 3h · rising · 30.04 inHg
Now
1017.3
mb
3h
+0.7
mb
12h
+0.3
mb
24h
0.0
mb
Regime · FAIR
STORM
RAIN
CHANGE
FAIR
DRY
24h · Pressure · mb
range 1016–1018
1010RAIN|CHG1015CHG|FAIR10201025FAIR|DRY-21h-18h-15h-12h-9h-6h-3h-24hNOW1018.21015.51017.2
−24h−18h−12h−6hnow
Fair, steady air — a quiet anticyclone holds the sky.
Key Biscayne, FL
Air quality
25
AQI
Good
↓-9 in 6h

AQI 25 (Good), driven by PM2.5. AQI down 9 over the last 6 hours (gradual decline). PM scrubbed by 2 hours of recent rain — PM2.5 down to 4.5 µg/m³, PM10 to 7.6 µg/m³.

OK No precautions needed for the general population; unusually sensitive individuals may consider limiting prolonged outdoor exertion.

PM 2.5DRIVERGood
4.5μg/m³
PM 10Good
8μg/m³
NO₂Good
1μg/m³
OzoneGood
42μg/m³
UV IndexLow
0.7

What's driving it

PM × Wind × Precip

PM scrubbed by 2 hours of recent rain — PM2.5 down to 4.5 µg/m³, PM10 to 7.6 µg/m³.

PM2.5/PM10
0.59
Wind
breezy
Recent rain
2h in last 6h
Pattern
washed out

Trends

Seven days of AQI and PM2.5.

Hourly air-quality data from the Copernicus Atmosphere Monitoring Service, charted across the past and next several days. Dashed lines mark the AQI breakpoints at 50 (Good → Moderate) and 100 (Moderate → Unhealthy for Sensitive Groups).

7-DAY AQI TREND50100SUNMONTUEWEDTHUFRISATSUN7-DAY PM2.5 TREND · μg/m³300
Key Biscayne, FL
Sky cover · visibility · 24h
Cloud cover
100%
OVERCAST
100%0%−24h−18h−12h−6hnow
Visibility
40.6mi
UNLIMITED
54 mi0 mi−24h−18h−12h−6hnow
Earth · GOES-19 ABI
Full Disk · Visible · GeoColor
GOES-19 full disk Visible · GeoColor
True-color daytime, blue/IR sandwich at night
12:25 UTC · Key Biscayne, FL · NOAA NESDIS / STAR · up to 10848 px
Continental US · GOES-19 ABI
CONUS Sector · Visible · GeoColor
GOES-19 CONUS Visible · GeoColor
Daytime true-color, blue-light/IR sandwich at night
12:25 UTC · Key Biscayne, FL · NOAA NESDIS / STAR · 5-min cadence · up to 10000 px
Key Biscayne, FL
Satellite · infrared · animated
Key Biscayne, FL
Loading IR frames…
IR · cloud-top temp© RainViewer · Carto
Key Biscayne, FL
Almanac · Sunday, July 5
If the first of July be rainy weather, 'twill rain more or less for four weeks together.
Civil dawn
6:09 AM
Sunrise
2:34 AM
Daylight
13h 41m
Sunset
4:15 PM
Civil dusk
8:42 PM
Planting note
Harvest early potatoes. Begin drying onions on the surface.
Key Biscayne, FL
The moon
Waning Gibbous
73% illuminated
Moonrise
11:29 PM
Moonset
11:35 AM
In sign
♓︎ Pisces
Key Biscayne, FL
Microseason
Jul 1–5

Midyear heat — the wet season grip

weather
Jan 151% of the yearDec 31

Read this microseason across nine climate regions →

Key Biscayne at a glance

  • Today vs. normal: 4°F below the seasonal normal for this latitude
  • Last frost: January 20 (climatological average for this latitude)
  • Microseason: Jul 1–5
  • Planting window: Harvest early potatoes. Begin drying onions on the surface.

ZIP code: 33149

16-Day Forecast — Key Biscayne

  1. Sun86°78°34%
  2. Mon86°79°45%
  3. Tue89°83°19%
  4. Wed90°84°6%
  5. Thu89°86°5%
  6. Fri89°85°20%
  7. Sat90°86°22%
  8. Sun89°85°15%
  9. Mon89°84°21%
  10. Tue87°80°22%
  11. Wed89°84°19%
  12. Thu90°85°37%
  13. Fri89°86°45%
  14. Sat89°85°42%
  15. Sun89°85°52%
  16. Mon88°86°32%

Forecast data from Open-Meteo (CC BY 4.0).

Right now in the garden

Peak growing season

As of July 5, the growing season is at its peak — frost is months away. Continue succession-planting beans and summer squash. Start fall brassicas (broccoli, cabbage, kale) from seed indoors for transplanting in late summer.

SPC Convective Outlook

Storm Prediction Center — Key Biscayne

SPC includes Key Biscayne in the general thunderstorm area today — no severe risk, but storms are possible.

  • TODAYTSTMGeneral Thunderstorms
  • TOMORROWTSTMGeneral Thunderstorms
  • DAY 3TSTMGeneral Thunderstorms

Thunderstorms possible. Not severe, but capable of producing lightning and brief heavy rain.

Source: NOAA / NWS Storm Prediction Center categorical convective outlook. Outlooks are re-issued multiple times per day; this page reflects the most recent SPC polygons covering the city’s coordinates.

January 1–5: The year turns in trade winds.January 6–10: Reefs reflect clear winter light.January 11–15: Mangrove buds swell with green.January 16–20: Hibiscus opens in January sun.January 21–25: Early-blooming aster brings gold.January 26–31: Last cold breath, green rising.February 1–5: Plumeria and ceiba crown the canopy.February 6–10: Coral spawn timing aligns with moon.February 11–15: Morning dew lingers on new leaves.February 16–20: Trade-wind rhythm softens slightly.February 21–25: Humidity breaks the dry season spell.February 26–28: Mist rises where rain falls inland.March 1–5: Green thickens in every direction.March 6–10: Hidden creatures awaken in dampness.March 11–15: Fruiting cycles deepen as rains persist.March 16–20: Wings emerge from green.March 21–25: Light holds the horizon.March 26–31: Coral blooms begin.April 1–5: Thunder rolls across the sea.April 6–10: Migrants pour southward.April 11–15: Green deepens in all things.April 16–20: Rain paints the sky.April 21–25: Green shoots rise from the shore.April 26–30: Heat breaks the last restraint.May 1–5: Lei Day—flowers crown the islands.May 6–10: Rain falls on greening grain.May 11–15: Green life breaks upward.May 16–20: Flowers spill across the islands.May 21–25: Summer arrives in thunder.May 26–31: Frogs sing the summer in.June 1–5: First trades stir the ceiba canopy.June 6–10: Afternoon showers claim the ritual.June 11–15: Easterly waves thread the Atlantic.June 16–20: Reef polyps synchronize in moonlight.June 21–25: The sun reaches its zenith turn.June 26–30: Lightning bugs dance above the flooded lowlands.July 1–5: Midyear heat — the wet season grip.July 6–10: Warm breeze across the mangrove maze.July 11–15: Storm surge begins its rhythm.July 16–20: Juvenile raptors test the thermals.July 21–25: The earth releases its breath — humidity peaks.July 26–31: Fruits swell in the tropical canopy.August 1–5: August opens — storms become routine.August 6–10: Autumn whispers in the trade wind shift.August 11–15: Cool winds find their path again.August 16–20: Cicadas hum through the heat.August 21–25: Trade winds gather strength.August 26–31: Hurricane season intensifies.September 1–5: Peak storm season dawns.September 6–10: Wet-season rains peak.September 11–15: Mid-season storm lull.September 16–20: Equinox approaches.September 21–25: Storm intensity ebbs slightly.September 26–30: Late-season storms persist.October 1–5: Easterly waves train across the basin.October 6–10: Hurricane season's second peak.October 11–15: Seasonal wind shift emerges.October 16–20: Atlantic storms retreat.October 21–25: Trade winds solidify.October 26–31: Dry season's arrival.November 1–5: Last storms clear the horizon.November 6–10: Dry season takes hold.November 11–15: Migratory arrivals from the north.November 16–20: The emerald deepens.November 21–25: Dust veil settles.November 26–30: Harvest calm descends.December 1–5: Deep dry season opens.December 6–10: Winter trades blow strong.December 11–15: Solstice approaches in green silence.December 16–20: The sun turns again.December 21–25: Solstice—renewal in stillness.December 26–31: Year's end in tropical stillness.🌱February 14 — First skunk-cabbage spathes thaw their way up☀️March 20 — Spring equinox — day and night balance🌸April 5 — Cherry blossoms peak in the parks🐦May 10 — Warbler migration peaks along the coast✨May 25 — First fireflies scout the meadows at dusk🌞June 21 — Summer solstice — longest day🦗July 25 — Peak cicada chorus in the afternoons🌊August 18 — Warmest sea-surface temperatures of the year🍂September 22 — Autumn equinox — the slow turn❄️October 25 — First widespread frost in the suburbs🍁November 10 — Peak leaf color across the Hudson Valley🌙December 21 — Winter solstice — longest night

Microseason · July 1–5

Midyear heat — the wet season grip

July arrives at full tropical intensity. Afternoon showers violent and brief. Trade winds weaken. Air feels solid with moisture and warmth.

Day 186 of 365 · Wedge 37 of 72

The solar year drawn as a wheel of 72 five-day windows. Each wedge is one microseason; the four colored arcs mark winter, spring, summer, and autumn; the small icons sit at notable phenological events. The crimson pointer creeps clockwise as the year turns.

Planting calendar

MonthPlantHarvest
January——
Februarylettuce, peas, spinach, radishes—
Marchlettuce, peas, spinach, radishes, tomatoes, peppers, beans, squash—
Apriltomatoes, peppers, beans, squash—
Maytomatoes, peppers, beans, squashlettuce, peas, radishes
June—lettuce, peas, radishes
July—tomatoes, beans, summer squash
August—tomatoes, beans, summer squash
September—tomatoes, beans, summer squash
Octoberfall brassicas, garlic (overwinter), carrotswinter squash, tomatoes (last)
Novemberfall brassicas, garlic (overwinter), carrots—
December——

A year in weather

In Key Biscayne, August runs warmest near 83°F and January coldest around 69°F, while September is the wettest month (6.7 inches) and February the driest (1.8 inches).

MonthMean tempPrecipRainy days
January69°1.9″20
February69°1.8″17
March72°1.9″19
April75°2.0″18
May78°3.8″23
June81°6.5″27
July82°4.1″29
August83°5.0″30
September81°6.7″29
October78°5.1″27
November74°2.3″19
December71°1.8″20

Regional context

By the nearest station's NOAA NCEI 1991-2020 normals, Key Biscayne sees 69°F Januarys and 82°F Julys, a 13°F range, plus around 42.9 inches of precipitation across 278 days.

Precipitation in Key Biscayne runs summer-dominant: September averages 6.7 inches across 29.1 days of warm-season storms, while February drops to 1.8 inches over 16.5 rainy days of drier cool air. That puts Key Biscayne in a summer-convective cohort with places like Fisher Island, FL, Coral Gables, FL and Miami, FL.

Key Biscayne rarely sees a hard freeze — its coldest month sits near 69°F — so planting spans most of the calendar. Heat peaks in August around 83°F, which confines cool-season crops to the shoulders of summer. Key Biscayne's coastal lots stay 4-7°F milder overnight than Key Biscayne's inland parcels.

Similar climates: Fisher Island, FL, Coral Gables, FL, Miami, FL, South Miami, FL, Pinecrest, FL.

Frequently asked

When does it freeze in Key Biscayne?
Frost typically leaves Key Biscayne by mid-February and returns to Key Biscayne near mid-December.
What is the rainy season in Key Biscayne?
September is the wettest month in Key Biscayne, about 6.7 inches on average; the year totals roughly 43 inches.
What is the warmest month in Key Biscayne?
Key Biscayne peaks in August, when the mean runs near 83°F.
What is the coldest month in Key Biscayne?
January is Key Biscayne's coldest month, averaging about 69°F.
When can I start a vegetable garden in Key Biscayne?
Hardy spring crops go in near mid-February in Key Biscayne; tender peppers and squash wait 10–14 days.
How many rainy days does Key Biscayne get?
Expect roughly 278 wet days a year in Key Biscayne.
What hardiness zone is Key Biscayne?
Since January in Key Biscayne averages 69°F, Key Biscayne's USDA zone follows that floor — confirm it by ZIP.
What is the 10-day forecast for Key Biscayne?
Key Biscayne's extended outlook — daily high and low temperatures and precipitation chances for each upcoming day — is in the daily forecast above.
Will it rain this week in Key Biscayne?
See this week's day-by-day rain chances for Key Biscayne in the daily forecast above, and the next 24 hours in the hourly chart.
What is the weather like right now in Key Biscayne?
Current conditions for Key Biscayne and the next 24 hours — temperature, precipitation chance, and wind by the hour — are in the hourly forecast chart above.
How often is the Key Biscayne forecast updated?
The Key Biscayne forecast on this page is built from Open-Meteo weather-model data and refreshes regularly through the day.
When are sunrise and sunset in Key Biscayne?
Today's sunrise and sunset times for Key Biscayne are in the Almanac section above, along with civil dawn, civil dusk, and day length. Day length is longest near the summer solstice and shortest near the winter solstice.
How accurate is the weather forecast for Key Biscayne?
The next few days in Key Biscayne's forecast are the most reliable; accuracy declines beyond about a week as weather-model uncertainty grows.

Climate

Set in a humid subtropical zone, Key Biscayne, Florida swings from 69°F in the heart of winter to 82°F at midsummer — a 13°F arc.

In a typical year Key Biscayne records about 43 inches of precipitation on around 278 days.

Key Biscayne's 13°F range, set by its 25.7°N position, drives frost timing and what thrives in Key Biscayne.

All cities in Florida →

Miami, FL weather →

ZIP codes in Key Biscayne

  • 33149

Climate normals from the Open-Meteo Climate API. Köppen approximation from NOAA NCEI U.S. Climate Regions. See methodology for data sources, editorial rules, and corrections. Maintainer: Brian Tighe.