Johnson City weather in September

In September, Johnson City sees average daytime highs of 74°F and overnight lows near 57°F, with 3.6 in of rain across 10.4 wet days and about 12.2 hours of daylight. It is the 4th-warmest and 10th-wettest month of the year here.

Highs ease over the month, from about 78°F in the first days to 71°F by the end. The sky is clear or mostly clear about 36% of the time in September, and the air most often feels dry.

Daylight stretches from about 12 h 48 min at the start of September to 11 h 42 min by month's end. Set against the rest of the year, September is Johnson City's 3rd-clearest and 9th-windiest month. For the whole year in context, see Johnson City's year-round climate.

Daytime high
74°
4th warmest
Overnight low
57°
9th coldest
Rainfall
3.6 in
10.4 wet days
Daylight
12 h 12 min
6:17 AM – 6:31 PM
Cloud cover
54%
3rd clearest
Wind
4 mph
9th windiest
Solar energy
4.58 kWh/m²
Travel score
6.8
out of 10

Johnson City is city in Washington, Carter, and Sullivan counties in Tennessee, United States.

Density
589/km²
people per km²
Founded
1856

Air quality: WHO Ambient Air Quality Database. Density & description: Wikidata (CC0), GeoNames.

Temperature in September

Average highAverage lowShaded bands: 10–90% of days

Highs ease over the month, from about 78°F in the first days to 71°F by the end.

A typical September day in Johnson City reaches about 74°F in the afternoon and slips back to 57°F overnight — a 18°F spread between the day's warmth and the night's chill. On most days the high lands between 67°F and 82°F. Set against its neighbours, September runs about 5°F cooler than August and about 10°F warmer than October.

40°50°60°70°80°151015202530
Avg high (°F)Avg low (°F)
17861
27861
37861
47860
57760
67760
77760
87759
97659
107659
117658
127658
137558
147558
157557
167557
177457
187456
197456
207356
217355
227355
237355
247254
257254
267254
277153
287153
297152
307052

How September really feels in Johnson City

Once humidity and wind are folded in, September averages 0 days that feel above 90°F and 0 that feel at or below 32°F — the comfort signal a plain temperature reading hides.

Days feeling ≥ 90°F
0
heat index over the day's high
Days feeling ≤ 32°F
0
wind chill below the day's low

September sits comfortably in between — no days that feel dangerously hot or drop to a hard freeze once humidity and wind are folded in.

Johnson City weather by month

How September compares with the rest of the year at a glance. September is the 4th-warmest and 10th-wettest month here — the current month is highlighted below.

MonthHigh / Low (°F)Rainfall (inches)Wet daysSnow daysDaylight (hours)Travel score
Jan44° / 28°4.3134.99.80.6
Feb47° / 30°3.812.34.810.61.4
Mar55° / 36°4.813.63.411.73.3
Apr64° / 45°4.4131.212.95.4
May71° / 53°4.214.4013.95.9
Jun77° / 61°4.216.4014.45.8
Jul80° / 64°4.217014.25.5
Aug79° / 63°3.814013.46.0
Sep74° / 57°3.610.4012.26.8
Oct65° / 46°3.09.40.311.16.1
Nov55° / 36°3.49.81.210.13.5
Dec47° / 31°4.211.73.89.61.3

Cloud cover in September

ClearMostly clearPartly cloudyMostly cloudyOvercast

The sky is clear or mostly clear about 36% of the time in September.

Beyond those clear spells, partly cloudy skies cover about 20% of September, with mostly cloudy or overcast conditions the remaining 44%.

0%25%50%75%100%151015202530
Clearer (%)Cloudier (%)
15644
25644
35644
45644
55644
65743
75743
85842
95842
105842
115842
125743
135842
145743
155644
165644
175545
185446
195545
205446
215446
225446
235446
245545
255644
265644
275644
285743
295743
305743

Chance of precipitation in September

Any precipitation

Johnson City gets around 3.6 in of rain over 10.4 wet days in September. The line is the day-by-day chance of measurable precipitation.

Day to day, the chance of measurable rain averages around 34% and peaks near 41% on the wettest days. The odds ease toward the end of the month.

0%10%20%30%40%50%151015202530
Rain chance (%)
141
241
340
439
539
638
737
836
935
1034
1133
1232
1332
1431
1531
1631
1732
1832
1932
2032
2133
2233
2332
2432
2532
2631
2731
2830
2930
3030

Humidity in September

DryComfortableHumidMuggyOppressiveMiserable

Most of September feels dry — the stacked bands show each day's mix of comfort levels, read off the dew point.

By dew point, September lands in the dry band about 33% of days. Sticky, muggy-or-worse air turns up on roughly 9% of them.

0%25%50%75%100%151015202530
Dry (%)Comfortable (%)Humid (%)Muggy (%)
113214322
214234221
316244020
417253919
518263718
620283617
721293415
823303314
924313213
1026323112
1127323011
1228332910
132933299
143034288
153134278
163234277
173335266
183435256
193535245
203635245
213834235
224034224
234233214
244432204
254631193
264831183
275030173
285229163
295428153
305627143

Wind in September

Winds average 4 mph in September.

Across September, daily wind ranges from about 3 mph on the calmest days to 4 mph at its breeziest. It stays fairly steady from day to day.

0246810151015202530
Wind speed (mph)Feels
13calm
24calm
34calm
44calm
54calm
64calm
74calm
84calm
94calm
104calm
114calm
124calm
134calm
144calm
154calm
164calm
174calm
184calm
194calm
204calm
214calm
224calm
234calm
244calm
254calm
264calm
274calm
284calm
294calm
304calm

Sunrise & sunset in September

DaylightNight

Daylight runs from about 12 h 48 min at the start of September to 11 h 42 min by month's end. The lit band spans sunrise to sunset each day.

Days shrink by about 66 minutes over September. Sunrise moves from 6:05 AM to 6:28 AM, and sunset from 6:53 PM to 6:09 PM.

12 AM4 AM8 AM12 PM4 PM8 PM12 AM151015202530
Daylight (h)Sunrise (AM)Sunset (PM)
112.86:056:53
212.86:066:52
312.76:066:50
412.76:076:49
512.76:086:47
612.66:096:46
712.66:106:44
812.56:106:43
912.56:116:41
1012.56:126:40
1112.46:136:38
1212.46:146:37
1312.36:146:35
1412.36:156:34
1512.36:166:32
1612.26:176:31
1712.26:186:29
1812.16:196:27
1912.16:196:26
2012.16:206:24
2112.06:216:23
2212.06:226:21
2312.06:236:20
2411.96:236:18
2511.96:246:17
2611.86:256:15
2711.86:266:14
2811.86:276:12
2911.76:286:10
3011.76:286:09

Solar energy in September

Daily solar energy (kWh/m²)

Average shortwave solar energy reaching the ground each day in September, about 4.58 kWh/m².

For context, solar energy here swings from a low near 2.15 kWh/m² to a high of 6.06 kWh/m² in June across the year — September's 4.58 kWh/m² falls in the middle.

0246151015202530
Solar energy (kWh/m²)Level
15.0Bright
25.0Bright
35.0Bright
45.0Bright
55.0Bright
64.9Bright
74.9Bright
84.9Bright
94.8Bright
104.8Bright
114.8Bright
124.7Bright
134.7Bright
144.7Bright
154.6Bright
164.6Bright
174.5Bright
184.5Bright
194.5Bright
204.4Bright
214.4Bright
224.3Bright
234.3Bright
244.3Bright
254.3Bright
264.3Bright
274.2Bright
284.2Bright
294.2Bright
304.2Bright
Planning a trip in September

Is September a good time to visit Johnson City?

Our two travel scores rate September for general sightseeing and for beach or pool weather — 0 (poor) to 10 (ideal).

6.8
Sightseeing
1st-best month of the year
5.5
Beach & pool
2nd-best month of the year

September is a reasonable time to visit Johnson City for sightseeing.

What to pack for Johnson City in September

From September's temperature range, rain chance, sun and wind — what's worth putting in the bag.

In September, Johnson City sees daytime highs around 74°F and nights near 57°F. Worth packing: light clothes, rain gear and sun protection. About 10 days see rain.

light clothesrain gearsun protection

UV index in Johnson City in September

LowModerateHighVery highExtreme

Clear-sky midday UV in September peaks around 7 — enough to warrant sun protection. The full-year curve, shaded by WHO exposure level, is below.

Under clear skies, the midday UV index in Johnson City peaks around July 13 at about 10 (very high) — sunscreen, a hat and midday shade are essential. It bottoms out near December 20 at about 2 (moderate).

The index reaches 3 or more — the level where the WHO recommends sun protection — in 10 months of the year.

025710JanFebMarAprMayJunJulAugSepOctNovDecModerateHighVery highHighModerateJul 13UV 10Dec 20UV 2
UV index (midday)Level
Jan3Moderate
Feb4Moderate
Mar6High
Apr7High
May8Very high
Jun9Very high
Jul10Very high
Aug8Very high
Sep7High
Oct5Moderate
Nov4Moderate
Dec2Moderate

Air quality in Johnson City in September

GoodModeratePoorUnhealthyVery unhealthy

Average fine-particle pollution (PM2.5) through the year — so you can see where September falls, not just the annual average.

Air quality in Johnson City is worst in July — around 18 µg/m³ PM2.5 (moderate), about 2.6× the cleanest month (December, 7 µg/m³).

Modeled monthly averages (CAMS reanalysis, 2015–2024).

01020JanFebMarAprMayJunJulAugSepOctNovDecGoodModerateGoodJul 1618 µg/m³Dec 217 µg/m³
PM2.5 (µg/m³)Level
Jan7Good
Feb9Good
Mar10Good
Apr11Good
May13Moderate
Jun16Moderate
Jul18Moderate
Aug15Moderate
Sep12Good
Oct8Good
Nov8Good
Dec7Good
Location & terrain

Where is Johnson City?

Johnson City sits at 36.3°N, 82.4°W, 1,634 ft above sea level, in United States. The nearest listed city is Kingsport, 20 mi away.

Topography around Johnson City

How much the land rises and falls, and what covers it, within 2, 10 and 50 miles of Johnson City.

Within 2 miles, the terrain around Johnson City has only modest variations in elevation — a maximum elevation change of 607 ft around an average of 1,719 ft above sea level; within 10 miles, large variations in elevation — a maximum elevation change of 2,418 ft; within 50 miles, very significant variations in elevation — a maximum elevation change of 5,682 ft.

The land around Johnson City is covered by trees (46%), grassland (27%) and artificial surfaces (27%) within 2 miles, trees (59%) and grassland (35%) within 10 miles, and trees (78%) and grassland (20%) within 50 miles.

2 miles
607 ft
10 miles
2,418 ft
50 miles
5,682 ft
treesgrasslandcroplandartificial surfacesbare terrainwater
September weather nearby: Kingsport 20 mi · Bristol 22 mi · Bristol 22 mi · Greeneville 29 mi · Boone 39 mi · Asheville 50 mi · Morristown 53 mi · Lenoir 53 mi

United States travel facts

Power plugs
Type A / B
120 V · 60 Hz
Prices
≈ 100% of US
price level, 2025
GDP per capita
$90,027
2025
Happiness
6.8 / 10
World Happiness, 2025
Safe drinking water
98%
of population, 2024
Homicide rate
5.8
per 100k, 2023
Road deaths
12.7
per 100k/yr, 2019
Income group
High
World Bank
Religion
Protestant 47%unaffiliated 23%Roman Catholic 21%Jewish 2%

Sources: World Bank, US State Department, World Happiness Report, WHO/UNICEF, EF EPI, CIA World Factbook.

Data sources

Temperature, precipitation, cloud, humidity, wind and solar figures are a 1991–2020 climatology for Johnson City (36.3134°, -82.3535°, elevation 1,634 ft), computed from hourly ERA5 reanalysis — contains modified Copernicus Climate Change Service information. Sun figures are astronomical calculations, not observations. City data © GeoNames, CC BY 4.0. Map outlines from Natural Earth (public domain); interactive map © Google. UV index is derived from CAMS (Copernicus Atmosphere Monitoring Service) clear-sky UV data — contains modified Copernicus Atmosphere Monitoring Service information. Monthly air-quality (PM2.5) seasonality is from the CAMS EAC4 reanalysis (Copernicus Atmosphere Monitoring Service), scaled to the WHO annual mean where available. Topography is sampled from the Copernicus DEM GLO-90 elevation model (© ESA/Airbus) and ESA WorldCover 2021 land cover (CC BY 4.0).