Johnson City, Tennessee Weather
Thunder quiets the land. Day 93 of summer. Read this microseason across nine climate regions →
Johnson City weather forecast — hour by hour, 7-day outlook, NOAA radar
Conditions updated 10:21 AM EDT · Open-Meteo
- TodaySep 21Clear16%—90°66°—
- TuesdaySep 22Overcast40%0.61″86°67°-4°
- WednesdaySep 23Heavy Drizzle68%—77°59°-9°
- ThursdaySep 24Light Showers37%0.02″67°58°-10°
- FridaySep 25Overcast——76°50°+9°
- SaturdaySep 26Overcast——77°48°+1°
- SundaySep 27Overcast——70°54°-7°
Air quality now AQI 50 · Good
AQI 50 (Good), driven by PM2.5. AQI projected to climb to 64 over the next 6 hours. PM2.5 at 10.4 µg/m³ (AQI 53) with a 0.95 fine-to-coarse ratio and 4 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 during the projected peak around 7 PM.
What's driving it
Ozone × UV × Sky
Ozone at AQI 42 now. With UV 3.7 peaking around 1 PM under clear skies, surface ozone likely climbs to AQI 21.
- Present
- AQI 42
- UV peak
- 3.7 at 1 PM
- Sky at peak
- clear
- Projected peak
- AQI 21
PM × Wind × Precip
PM2.5 at 10.4 µg/m³ (AQI 53) with a 0.95 fine-to-coarse ratio and 4 mph wind — combustion smoke trapped in stagnant air, not road dust.
- PM2.5/PM10
- 0.95
- Wind
- calm
- Recent rain
- 0h in last 6h
- Pattern
- stagnant smoke
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).
September dries up ditches or breaks down bridges.
- Moonrise
- 4:51 PM
- Moonset
- 2:01 AM
- In sign
- ♑︎ Capricorn
Thunder quiets the land
Read this microseason across nine climate regions →
All 72 microseasons on the year wheel →
Johnson City at a glance
- Today vs. normal: Today averages 78°F (high 90°F, low 66°F), 12°F above the 66°F normal for Sep 21
- Last frost: April 19 (1991–2020 median, NOAA station 12 km away)
- Microseason: Sep 21–25
- Planting calendar: September — plant garlic (overwinter); harvest tomatoes, peppers, beans, summer squash, winter squash
16-Day Forecast — Johnson City
- Mon90°66°16%
- Tue86°67°40%
- Wed77°59°68%
- Thu67°58°37%
- Fri76°50°6%
- Sat77°48°1%
- Sun70°54°3%
- Mon80°54°4%
- Tue82°58°10%
- Wed80°56°23%
- Thu82°59°23%
- Fri85°57°26%
- Sat82°59°20%
- Sun67°63°14%
- Mon66°47°32%
- Tue65°39°30%
Forecast data from Open-Meteo (CC BY 4.0).
Live wind & temperature near Johnson City
Interactive wind and temperature map centered on Johnson City — it loads in your browser. Open the full weather map.
Right now in the garden
Fall planting + final harvests
As of September 21, the season's first frost (typically October 24) is approaching. Pick what frost-tender plants still carry before the next cold front. This city's planting calendar for September: plant garlic (overwinter); harvest tomatoes, peppers, beans, summer squash, and winter squash.
SPC Convective Outlook
Storm Prediction Center — Johnson City
SPC has placed Johnson City in the Marginal Risk category for severe thunderstorms today.
- TODAYMRGLMarginal Risk
- TOMORROWTSTMGeneral Thunderstorms
- DAY 3TSTMGeneral Thunderstorms
Isolated severe storms possible. Limited threat for hail or damaging wind.
Source: NOAA / NWS Storm Prediction Center categorical convective outlook.
Sun & seasons in Johnson City
Johnson City sits in Washington County, where the year’s longest day runs 14h 38m of daylight and its shortest just 9h 41m — a swing of +4h 58m 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 246 miles to the W. The nearest town Johnson City tracks is Mountain City, roughly 33 miles to the ENE.
Planting calendar
| Month | Plant | Harvest |
|---|---|---|
| March | lettuce, peas, spinach, radishes | — |
| April | lettuce, peas, spinach, radishes | radishes |
| May | tomatoes, peppers, beans, squash | lettuce, peas, spinach, radishes |
| June | tomatoes, peppers, beans, squash | lettuce, peas, spinach, radishes, summer squash |
| July | tomatoes, peppers, beans, squash | lettuce, peas, tomatoes, peppers, beans, summer squash, garlic |
| August | beans, squash, fall brassicas, carrots | tomatoes, peppers, beans, summer squash, winter squash |
| September | garlic (overwinter) | tomatoes, peppers, beans, summer squash, winter squash |
| October | garlic (overwinter) | tomatoes, peppers, beans, summer squash, winter squash, fall brassicas, carrots |
| November | — | fall brassicas, carrots |
A year in weather
July is Johnson City's warmest stretch (~75°F) and January its coldest (~36°F); precipitation crests in July at 5.9 inches and ebbs in October to 2.8 inches.
| Month | Mean temp | Precip | Rainy days |
|---|---|---|---|
| January | 36° | 3.8″ | 13 |
| February | 39° | 3.8″ | 12 |
| March | 47° | 4.0″ | 13 |
| April | 56° | 3.8″ | 12 |
| May | 64° | 4.4″ | 13 |
| June | 71° | 5.2″ | 13 |
| July | 75° | 5.9″ | 14 |
| August | 74° | 4.2″ | 12 |
| September | 68° | 3.0″ | 9 |
| October | 57° | 2.8″ | 9 |
| November | 46° | 3.4″ | 10 |
| December | 39° | 3.9″ | 13 |
Regional context
Similar climates Central, TN, Pine Crest, TN, Watauga, TN
Per NOAA NCEI 1991-2020 normals, Johnson City runs from a 36°F January mean to 75°F in July, a 39°F seasonal spread, with near 48 inches of precipitation across about 142 wet days.
No season owns Johnson City's rain: July reaches 5.9 inches across 13.5 days and October keeps 2.8 inches on 8.9, an even spread through Johnson City's year. That lines Johnson City up with places like Central, TN, Pine Crest, TN and Watauga, TN, fed by overlapping storm tracks.
Around April 19, Johnson City sheds its freezing nights — peas, lettuce, spinach, and radishes go into Johnson City's beds. Tomatoes and peppers do best set out two weeks later in Johnson City, once nights clear the mid-40s°F. The season ends by October 24 in Johnson City, once hard frosts set back in. Open lawns in Johnson City whiten first when frost returns.
Similar climates: Central, TN, Pine Crest, TN, Watauga, TN, Jonesborough, TN, Oak Grove, TN.
Frequently asked
- When does it freeze in Johnson City?
- In Johnson City, expect the last spring frost near April 19; Johnson City's first autumn frost comes around October 24.
- What is the rainy season in Johnson City?
- Rainfall in Johnson City peaks in July near 5.9 inches, out of about 48 inches annually.
- What is the warmest month in Johnson City?
- July is Johnson City's warmest month, averaging about 75°F.
- What is the coldest month in Johnson City?
- Johnson City bottoms out in January, with a mean near 36°F.
- When can I start a vegetable garden in Johnson City?
- Time tomatoes in Johnson City for two weeks after April 19; peas and greens start at Johnson City's frost line.
- How many rainy days does Johnson City get?
- Expect roughly 142 wet days a year in Johnson City.
- What hardiness zone is Johnson City?
- Johnson City's hardiness zone tracks its winter low; with January near 36°F, check the USDA ZIP map for the exact zone.
- What is the 10-day forecast for Johnson City?
- Johnson City'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 Johnson City?
- See this week's day-by-day rain chances for Johnson City in the daily forecast above, and the next 24 hours in the hourly chart.
- What is the weather like right now in Johnson City?
- Current conditions for Johnson City and the next 24 hours — temperature, precipitation chance, and wind by the hour — are in the hourly forecast chart above.
- How often is the Johnson City forecast updated?
- The Johnson City forecast on this page is built from Open-Meteo weather-model data and refreshes regularly through the day.
- When are sunrise and sunset in Johnson City?
- Today's sunrise and sunset times for Johnson City 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 Johnson City?
- The next few days in Johnson City's forecast are the most reliable; accuracy declines beyond about a week as weather-model uncertainty grows.
Johnson City sits at 36.3°N; its climate zone is humid subtropical (Köppen approximation).
ZIP codes in Johnson City
- 37601
- 37602
- 37604
- 37605
- 37614
- 37615
- 37684