Chattanooga, Tennessee Weather

Thunder quiets the land. Day 93 of summer. Read this microseason across nine climate regions →

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

Chattanooga, TN
Monday, September 21 at 1:40 AM
74
°
Clear
Feels like
80°
Humidity
84%
Wind
3 mph
Sunrise
7:28 AM
Sunset
7:39 PM

Conditions updated 1:40 AM EDT · Open-Meteo

Chattanooga, TN
Hour by hour · 24h
24-Hour ForecastChattanooga, TN: 24-hour forecast. Temperatures range from 71 to 93 degrees Fahrenheit with a 31% chance of precipitation at 5 PM.
L 71°H 93°
Chattanooga, TN
7-day forecast
  1. Today
    Sep 21
    Overcast later
    31%
    93°71°
  2. Tuesday
    Sep 22
    Overcast
    67%
    90°69°-3°
  3. Wednesday
    Sep 23
    Thunderstorm
    58%
    81°67°-9°
  4. Thursday
    Sep 24
    Light Drizzle
    27%
    83°64°+2°
  5. Friday
    Sep 25
    Light Drizzle
    81°60°-2°
  6. Saturday
    Sep 26
    Overcast
    80°59°-1°
  7. Sunday
    Sep 27
    Overcast
    80°60°
Chattanooga, TN
Anemometer · 24h winds · from true
NESW
From · True
SE
138° · veering 111°
Direction
SE
138°
Sustained
3
mph
Gust
7
mph
Peak 24h
16
avg 3 mph
Beaufort · 1 · LIGHT AIR
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 3 mph · pk 16 mph @ 10:00p
0102030MPHB1B2B3B4B5B6-21h-18h-15h-12h-9h-6h-3h-24hNOWpk 234SUSTGUST
−24h−18h−12h−6hnow
Light breeze veering 111° from the se.
Chattanooga, TN
Barometer · 24h pressure · mb
STORMRAINCHANGEFAIRDRY9901000101010201030
Pressure · mb
1013.4
-0.3 mb in 3h · steady · 29.93 inHg
Now
1013.4
mb
3h
-0.3
mb
12h
-2.3
mb
24h
-2.2
mb
Regime · CHANGE
STORM
RAIN
CHANGE
FAIR
DRY
24h · Pressure · mb
range 10111016
9951000STORM|RAIN10051010RAIN|CHG1015CHG|FAIR10201025FAIR|DRY-21h-18h-15h-12h-9h-6h-3h-24hNOW1016.11010.91013.2
Air sits at the threshold — small shifts decide the day.
Air quality now AQI 58 · Moderate
Chattanooga, TN
Air quality
58
AQI
Moderate
+1 in 6h

AQI 58 (Moderate), driven by PM2.5. AQI flat over the last 6 hours (within ±3 points). PM2.5 at 15.1 µg/m³ (AQI 62) with a 0.98 fine-to-coarse ratio and 3 mph wind — combustion smoke trapped in stagnant air, not road dust.

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

PM 2.5DRIVERModerate
15.1μg/m³
PM 10Good
15μg/m³
NO₂Good
15μg/m³
OzoneGood
48μg/m³
UV IndexLow
0.0

What's driving it

PM × Wind × Precip

PM2.5 at 15.1 µg/m³ (AQI 62) with a 0.98 fine-to-coarse ratio and 3 mph wind — combustion smoke trapped in stagnant air, not road dust.

PM2.5/PM10
0.98
Wind
calm
Recent rain
0h in last 6h
Pattern
stagnant smoke
Chattanooga, TN
Sky cover · visibility · 24h
Cloud cover
0%
CLEAR
100%0%−24h−18h−12h−6hnow

Visibility
10.0mi
UNLIMITED
28 mi0 mi−24h−18h−12h−6hnow
Chattanooga, TN
Almanac · Monday, September 21
September dries up ditches or breaks down bridges.
Civil dawn
7:03 AM
Sunrise
7:28 AM
Daylight
12h 11m
Sunset
7:39 PM
Civil dusk
8:08 PM
Planting note
September — harvest tomatoes, peppers, beans, summer squash, winter squash
Chattanooga, TN
The moon
Waxing Gibbous
72% illuminated
Moonrise
4:59 PM
Moonset
2:16 AM
In sign
♑︎ Capricorn
Chattanooga, TN
Microseason
Sep 21–25

Thunder quiets the land

weather
Jan 172% of the yearDec 31

Read this microseason across nine climate regions →
All 72 microseasons on the year wheel →

Chattanooga at a glance

  • Today vs. normal: Today averages 82°F (high 93°F, low 71°F), 11°F above the 71°F normal for Sep 21
  • Last frost: March 24 (1991–2020 median, NOAA station 6 km away)
  • Microseason: Sep 21–25
  • Planting calendar: September — harvest tomatoes, peppers, beans, summer squash, winter squash

15-Day Forecast — Chattanooga

  1. Mon93°71°31%
  2. Tue90°69°67%
  3. Wed81°67°58%
  4. Thu83°64°27%
  5. Fri81°60°8%
  6. Sat80°59°2%
  7. Sun80°60°3%
  8. Mon82°53°5%
  9. Tue84°58°13%
  10. Wed86°68°23%
  11. Thu82°61°15%
  12. Fri83°55°16%
  13. Sat82°65°19%
  14. Sun83°68°26%
  15. Mon86°63°16%

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

Live wind & temperature near Chattanooga

Interactive wind and temperature map centered on Chattanooga — it loads in your browser. Open the full weather map.

Right now in the garden

Late season

As of September 21, the first frost (around November 9) is about 7 weeks away. Frost-tender plants keep producing until then. This city's planting calendar for September: harvest tomatoes, peppers, beans, summer squash, and winter squash.

SPC Convective Outlook

Storm Prediction Center — Chattanooga

SPC has placed Chattanooga in the Marginal Risk category for severe thunderstorms tomorrow.

  • TODAYTSTMGeneral Thunderstorms
  • TOMORROWMRGLMarginal Risk
  • DAY 3MRGLMarginal Risk

Isolated severe storms possible. Limited threat for hail or damaging wind.

Source: NOAA / NWS Storm Prediction Center categorical convective outlook.

Sun & seasons in Chattanooga

Chattanooga sits in Hamilton County, where the year’s longest day runs 14h 31m of daylight and its shortest just 9h 48m — a swing of +4h 44m between the June and December solstices. Clocks spring forward on Sunday, March 8, 2026 and fall back on Sunday, November 1, 2026.

Nashville, the state’s largest city, lies about 115 miles to the NW. The nearest town Chattanooga tracks is Kahite, roughly 67 miles to the ENE.

Air quality in Chattanooga

Air quality in Chattanooga’s county has held roughly steady since 2020; its cleanest year on record was 2025 (median AQI 44). See the full air-quality history for Chattanooga.

Planting calendar

MonthPlantHarvest
Marchlettuce, peas, spinach, radishesradishes
Aprillettuce, spinach, radishes, tomatoes, peppers, beans, squashlettuce, spinach, radishes
Maytomatoes, peppers, beans, squashlettuce, peas, spinach, radishes
Junebeans, squashlettuce, peas, beans, summer squash, garlic
Julytomatoes, peppers, beans, squashtomatoes, peppers, beans, summer squash
Augustbeans, squash, fall brassicas, carrotstomatoes, peppers, beans, summer squash, winter squash
Septembertomatoes, peppers, beans, summer squash, winter squash
Octobergarlic (overwinter)tomatoes, peppers, beans, summer squash, winter squash
Novembertomatoes, peppers, beans, summer squash, winter squash, fall brassicas, carrots
Decemberfall brassicas, carrots

A year in weather

Chattanooga peaks at about 79°F in July and bottoms near 39°F in January; December brings the heaviest rain (5.4 inches) and October the least (2.4 inches).

MonthMean tempPrecip
January39°5.1
February42°4.5
March50°5.3
April59°4.6
May67°3.6
June76°3.5
July79°4.1
August78°4.3
September73°2.8
October63°2.4
November50°4.1
December42°5.4

Regional context

Similar climates Ridgeside, TN, Red Bank, TN, East Ridge, TN

Drawing on modelled 1991-2020 normals (EC_Earth3P_HR model via Open-Meteo), Chattanooga's January averages 39°F and July 79°F — 40°F apart — while precipitation totals roughly 49.8 inches.

Chattanooga's precipitation spreads evenly across the seasons: December peaks at 5.4 inches, while October holds 2.4 inches — no season dominates Chattanooga's rain calendar. That lines Chattanooga up with places like Ridgeside, TN, Red Bank, TN and East Ridge, TN, fed by overlapping storm tracks.

Chattanooga's growing window opens around March 24, once Chattanooga's overnight lows stop freezing — sow peas, lettuce, spinach, and radishes. Warm-soil crops in Chattanooga wait about two weeks past Chattanooga's last frost, once the soil warms. Chattanooga's window closes around November 9 as Chattanooga's overnight lows return below freezing. In about half of years, Chattanooga's last freeze comes after March 24.

Similar climates: Ridgeside, TN, Red Bank, TN, East Ridge, TN, Harrison, TN, Walden, TN.

Frequently asked

When does it freeze in Chattanooga?
Chattanooga's last spring frost lands near March 24, and in Chattanooga the first fall frost follows around November 9.
What is the rainy season in Chattanooga?
Rainfall in Chattanooga peaks in December near 5.4 inches, out of about 50 inches annually.
What is the warmest month in Chattanooga?
On average July tops the year in Chattanooga at about 79°F.
What is the coldest month in Chattanooga?
The coldest stretch in Chattanooga falls in January, around 39°F on average.
When can I start a vegetable garden in Chattanooga?
Around March 24, start frost-hardy crops in Chattanooga; tomatoes and basil belong a fortnight later.
What hardiness zone is Chattanooga?
Because Chattanooga bottoms near 39°F in January, that winter low sets Chattanooga's USDA zone — verify by ZIP.
What is the 10-day forecast for Chattanooga?
Chattanooga'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 Chattanooga?
See this week's day-by-day rain chances for Chattanooga in the daily forecast above, and the next 24 hours in the hourly chart.
What is the weather like right now in Chattanooga?
Current conditions for Chattanooga and the next 24 hours — temperature, precipitation chance, and wind by the hour — are in the hourly forecast chart above.
How often is the Chattanooga forecast updated?
The Chattanooga forecast on this page is built from Open-Meteo weather-model data and refreshes regularly through the day.
When are sunrise and sunset in Chattanooga?
Today's sunrise and sunset times for Chattanooga 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 Chattanooga?
The next few days in Chattanooga's forecast are the most reliable; accuracy declines beyond about a week as weather-model uncertainty grows.

Chattanooga sits at 35.1°N; its climate zone is humid subtropical (Köppen approximation).

ZIP codes in Chattanooga

  • 37343
  • 37351
  • 37401
  • 37402
  • 37403
  • 37404
  • 37405
  • 37406
  • 37407
  • 37408
  • 37409
  • 37410
  • 37411
  • 37412
  • 37414
  • 37415
  • 37416
  • 37419
  • 37421
  • 37424
  • 37450

Climate normals: modelled 1991–2020 normals from the EC_Earth3P_HR climate model via the Open-Meteo Climate API, not station observations. Köppen approximation from NOAA NCEI U.S. Climate Regions. See methodology for data sources, editorial rules, and corrections. Maintainer: Brian Tighe.