Denville weather in August

In August, Denville sees average daytime highs of 81°F and overnight lows near 64°F, with 4.0 in of rain across 10.4 wet days and about 13.6 hours of daylight. It is the 2nd-warmest and 7th-wettest month of the year here.

Highs ease over the month, from about 83°F in the first days to 80°F by the end. The sky is clear or mostly clear about 28% of the time in August, and the air most often feels humid.

Daylight stretches from about 14 h 12 min at the start of August to 13 hours by month's end. Set against the rest of the year, August is Denville's 4th-clearest and 12th-windiest month. For the whole year in context, see Denville's year-round climate.

Daytime high
81°
2nd warmest
Overnight low
64°
11th coldest
Rainfall
4.0 in
10.4 wet days
Daylight
13 h 36 min
5:13 AM – 6:51 PM
Cloud cover
60%
4th clearest
Wind
5 mph
12th windiest
Solar energy
5.17 kWh/m²
Travel score
6.3
out of 10

Denville is town in Morris County, New Jersey, United States.

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

Temperature in August

Average highAverage lowShaded bands: 10–90% of days

Highs ease over the month, from about 83°F in the first days to 80°F by the end.

A typical August day in Denville reaches about 81°F in the afternoon and slips back to 64°F overnight — a 17°F spread between the day's warmth and the night's chill. On most days the high lands between 73°F and 89°F. Set against its neighbours, August runs about 2°F cooler than July and about 7°F warmer than September.

50°60°70°80°90°151015202531
Avg high (°F)Avg low (°F)
18366
28365
38365
48365
58365
68265
78265
88265
98265
108265
118265
128265
138265
148264
158164
168164
178164
188164
198164
208164
218163
228063
238063
248063
258063
268062
278062
288062
298062
307962
317962

How August really feels in Denville

Once humidity and wind are folded in, August 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

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

Denville weather by month

How August compares with the rest of the year at a glance. August is the 2nd-warmest and 7th-wettest month here — the current month is highlighted below.

MonthHigh / Low (°F)Rainfall (inches)Wet daysSnow daysDaylight (hours)Travel score
Jan36° / 22°3.59.35.59.40.0
Feb39° / 23°3.08.74.510.40.0
Mar47° / 31°4.310.94.111.71.5
Apr59° / 41°3.8110.813.14.4
May69° / 51°3.911.9014.36.1
Jun78° / 60°4.211.4014.96.4
Jul83° / 65°4.210.8014.65.6
Aug81° / 64°4.010.4013.66.3
Sep74° / 56°4.59.5012.36.9
Oct62° / 45°4.18.90.210.95.5
Nov51° / 35°3.38.30.99.72.5
Dec41° / 28°4.19.73.99.10.2

Cloud cover in August

ClearMostly clearPartly cloudyMostly cloudyOvercast

The sky is clear or mostly clear about 28% of the time in August.

Beyond those clear spells, partly cloudy skies cover about 20% of August, with mostly cloudy or overcast conditions the remaining 53%. Skies tend to open up as the month goes on.

0%25%50%75%100%151015202531
Clearer (%)Cloudier (%)
14654
24654
34654
44654
54654
64654
74654
84654
94654
104654
114654
124654
134654
144753
154753
164753
174753
184753
194852
204852
214852
224951
234951
245050
254951
265050
275050
285050
295050
304951
314951

Chance of precipitation in August

Any precipitation

Denville gets around 4.0 in of rain over 10.4 wet days in August. 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 37% on the wettest days. The odds ease toward the end of the month.

0%10%20%30%40%50%151015202531
Rain chance (%)
137
236
336
436
536
636
736
837
937
1037
1137
1237
1337
1437
1537
1636
1736
1835
1935
2034
2133
2232
2331
2430
2529
2628
2728
2827
2927
3027
3127

Humidity in August

DryComfortableHumidMuggyOppressiveMiserable

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

By dew point, August lands in the humid band about 27% of days. Sticky, muggy-or-worse air turns up on roughly 30% of them.

0%25%50%75%100%151015202531
Dry (%)Comfortable (%)Humid (%)Muggy (%)Oppressive (%)
1152030279
2152029279
3162029269
4162029269
5162028269
6172028269
7172028269
8172027269
9172027269
10182027268
11182127268
12182127268
13182127268
14192127267
15192127257
16192227257
17192227247
18202227246
19202327236
20212327236
21222327225
22222327225
23232427215
24242426215
25252426205
26262426195
27272425185
28282425185
29292424175
30302424175
31312424175

Wind in August

Winds average 5 mph in August, the calmest month.

Across August, daily wind ranges from about 5 mph on the calmest days to 6 mph at its breeziest. It stays fairly steady from day to day.

0246810151015202531
Wind speed (mph)Feels
15calm
25calm
35calm
45calm
55calm
65calm
75calm
85calm
95calm
105calm
115calm
125calm
135calm
145calm
155calm
165calm
175calm
185calm
195calm
205calm
215calm
225calm
235calm
245calm
255calm
265calm
275calm
285calm
295calm
305calm
316calm

Sunrise & sunset in August

DaylightNight

Daylight runs from about 14 h 12 min at the start of August to 13 hours by month's end. The lit band spans sunrise to sunset each day.

Days shrink by about 72 minutes over August. Sunrise moves from 4:58 AM to 5:28 AM, and sunset from 7:10 PM to 6:28 PM.

12 AM4 AM8 AM12 PM4 PM8 PM12 AM151015202531
Daylight (h)Sunrise (AM)Sunset (PM)
114.24:587:10
214.24:597:09
314.15:007:08
414.15:017:07
514.15:027:06
614.05:037:05
714.05:047:03
814.05:057:02
913.95:067:01
1013.95:077:00
1113.85:086:58
1213.85:096:57
1313.85:106:56
1413.75:116:54
1513.75:126:53
1613.65:136:51
1713.65:146:50
1813.65:156:48
1913.55:166:47
2013.55:176:45
2113.45:186:44
2213.45:196:42
2313.45:206:41
2413.35:216:39
2513.35:226:38
2613.25:236:36
2713.25:246:35
2813.15:256:33
2913.15:266:31
3013.05:276:30
3113.05:286:28

Solar energy in August

Daily solar energy (kWh/m²)

Average shortwave solar energy reaching the ground each day in August, about 5.17 kWh/m².

For context, solar energy here swings from a low near 1.72 kWh/m² to a high of 5.95 kWh/m² in June across the year — August's 5.17 kWh/m² falls in the middle.

0246151015202531
Solar energy (kWh/m²)Level
15.5Bright
25.5Bright
35.5Bright
45.5Bright
55.4Bright
65.4Bright
75.4Bright
85.3Bright
95.3Bright
105.3Bright
115.2Bright
125.2Bright
135.2Bright
145.2Bright
155.1Bright
165.1Bright
175.1Bright
185.1Bright
195.1Bright
205.0Bright
215.0Bright
225.0Bright
235.0Bright
245.0Bright
255.0Bright
264.9Bright
274.9Bright
284.9Bright
294.8Bright
304.8Bright
314.8Bright
Planning a trip in August

Hazard calendar for Denville

In seasonPeak

In August, Denville sits inside its atlantic hurricane season. The full year is below, with each hazard's peak months called out.

Denville sits in the Atlantic hurricane belt; the season peaks August–October.

Atlantic hurricane
Jan
Feb
Mar
Apr
May
Jun
Jul
Aug
Sep
Oct
Nov
Dec

Is August a good time to visit Denville?

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

6.3
Sightseeing
3rd-best month of the year
6.6
Beach & pool
2nd-best month of the year

August is a reasonable time to visit Denville for sightseeing. The water and warmth also suit a beach or pool day.

What to pack for Denville in August

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

In August, Denville sees daytime highs around 81°F and nights near 64°F. Pack light clothes. Worth having: rain gear and sun protection. About 10 days see rain.

light clothesrain gearsun protection

Sea temperature near Denville in August

The nearest coast averages about 74°F in August — the other half of the beach question. The full-year curve and swim-comfort zones are below.

The sea at the nearest coast (about 37 mi away) is warmest in August at about 74°F and coldest in February near 40°F.

It's comfortable for a long swim from Jun 30 to Sep 26 — about 2.9 months when the water holds above 68°F.

40°50°60°70°80°JanFebMarAprMayJunJulAugSepOctNovDecbracingcoolrefreshingwarmcomfortable to swim
Sea temperature (°F)Comfort
Jan43Bracing
Feb40Bracing
Mar41Bracing
Apr46Bracing
May55Bracing
Jun65Cool
Jul72Refreshing
Aug74Refreshing
Sep71Refreshing
Oct63Cool
Nov55Bracing
Dec48Bracing

UV index in Denville in August

LowModerateHighVery highExtreme

Clear-sky midday UV in August peaks around 6 — enough to warrant sun protection. The full-year curve, shaded by WHO exposure level, is below.

Under clear skies, the midday UV index in Denville peaks around July 11 at about 8 (very high) — sunscreen and a hat are worth it in the middle of the day. It bottoms out near December 22 at about 1 (low).

The index reaches 3 or more — the level where the WHO recommends sun protection — in 8 months of the year.

025710JanFebMarAprMayJunJulAugSepOctNovDecLowModerateHighVery highHighModerateLowJul 11UV 8Dec 22UV 1
UV index (midday)Level
Jan2Low
Feb3Moderate
Mar5Moderate
Apr6High
May7Very high
Jun8Very high
Jul8Very high
Aug6High
Sep6High
Oct3Moderate
Nov2Moderate
Dec1Low

Air quality in Denville in August

GoodModeratePoorUnhealthyVery unhealthy

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

Air quality in Denville is worst in July — around 17 µg/m³ PM2.5 (moderate), about 1.9× the cleanest month (November, 9 µg/m³).

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

01020JanFebMarAprMayJunJulAugSepOctNovDecGoodModerateGoodJul 1317 µg/m³Nov 159 µg/m³
PM2.5 (µg/m³)Level
Jan11Good
Feb13Moderate
Mar14Moderate
Apr14Moderate
May16Moderate
Jun16Moderate
Jul17Moderate
Aug15Moderate
Sep13Moderate
Oct10Good
Nov9Good
Dec10Good
Location & terrain

Where is Denville?

Denville sits at 40.9°N, 74.5°W, 505 ft above sea level, in United States. The nearest listed city is Parsippany, 3.7 mi away.

Topography around Denville

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

Within 2 miles, the terrain around Denville has only modest variations in elevation — a maximum elevation change of 482 ft around an average of 591 ft above sea level; within 10 miles, significant variations in elevation — a maximum elevation change of 1,266 ft; within 50 miles, large variations in elevation — a maximum elevation change of 2,425 ft.

The land around Denville is covered by trees (75%) within 2 miles, trees (81%) within 10 miles, and trees (69%) within 50 miles.

2 miles
482 ft
10 miles
1,266 ft
50 miles
2,425 ft
treesgrasslandcroplandartificial surfaceswater
August weather nearby: Parsippany 3.7 mi · Dover 4.3 mi · Randolph 6.2 mi · Morristown 6.8 mi · Madison 9.9 mi · Hopatcong Hills 11 mi · Wayne 11 mi · Livingston 11 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 Denville (40.8923°, -74.4774°, elevation 505 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. Tropical-cyclone seasons are the published climatological basin seasons (NOAA National Hurricane Center / regional warning centres). Sea temperatures are the NOAA OISST v2.1 1991–2020 monthly climatology (public domain), sampled at the nearest ocean point. 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).