Isahaya weather in July

In July, Isahaya sees average daytime highs of 27°C and overnight lows near 24°C, with 346 mm of rain across 16.6 wet days and about 13.9 hours of daylight. It is the 2nd-warmest and 2nd-wettest month of the year here.

Highs climb over the month, from about 25°C in the first days to 28°C by the end. The sky is clear or mostly clear about 26% of the time in July, and the air most often feels oppressive.

Daylight stretches from about 14 h 06 min at the start of July to 13 h 42 min by month's end. Set against the rest of the year, July is Isahaya's 10th-clearest and 9th-windiest month. For the whole year in context, see Isahaya's year-round climate.

Daytime high
27°
2nd warmest
Overnight low
24°
11th coldest
Rainfall
346 mm
16.6 wet days
Daylight
14 hours
5:26 AM – 7:25 PM
Cloud cover
68%
10th clearest
Wind
13 km/h
9th windiest
Solar energy
5.02 kWh/m²
Travel score
5.3
out of 10

Isahaya is city in Nagasaki Prefecture, Japan.

Density
422/km²
people per km²
Founded
2005

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

Temperature in July

Average highAverage lowShaded bands: 10–90% of days

Highs climb over the month, from about 25°C in the first days to 28°C by the end.

A typical July day in Isahaya reaches about 27°C in the afternoon and slips back to 24°C overnight — a 3°C spread between the day's warmth and the night's chill. On most days the high lands between 25°C and 29°C. Set against its neighbours, July runs about 3°C warmer than June and about 2°C cooler than August.

20°25°30°35°151015202531
Avg high (°C)Avg low (°C)
12523
22523
32523
42623
52623
62623
72623
82623
92624
102624
112724
122724
132724
142724
152724
162724
172724
182724
192825
202825
212825
222825
232825
242825
252825
262825
272825
282825
292825
302925
312925

How July really feels in Isahaya

Once humidity and wind are folded in, July averages 9 days that feel above 32°C and 0 that feel at or below 0°C — the comfort signal a plain temperature reading hides.

Days feeling ≥ 32°C
9
heat index over the day's high
Days feeling ≤ C
0
wind chill below the day's low

The story in July is heat — humidity pushes the afternoon "feels like" well above the raw temperature.

Isahaya weather by month

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

MonthHigh / Low (°C)Rainfall (mm)Wet daysSnow daysDaylight (hours)Travel score
Jan10° / 8010.80.610.12.1
Feb11° / 97100.410.82.5
Mar13° / 14912011.83.7
Apr17° / 13°16711.4012.85.3
May21° / 17°19710.8013.76.2
Jun24° / 21°44416.5014.15.5
Jul27° / 24°34616.6013.95.3
Aug29° / 25°18513.7013.25.2
Sep26° / 23°20211.9012.26.4
Oct22° / 18°1127.5011.27.3
Nov17° / 13°1069.1010.35.7
Dec12° / 9210.309.93.3

Cloud cover in July

ClearMostly clearPartly cloudyMostly cloudyOvercast

The sky is clear or mostly clear about 26% of the time in July.

Beyond those clear spells, partly cloudy skies cover about 10% of July, with mostly cloudy or overcast conditions the remaining 64%. Skies tend to open up as the month goes on.

0%25%50%75%100%151015202531
Clearer (%)Cloudier (%)
12179
22179
32278
42377
52377
62575
72575
82773
92773
102872
112971
123070
133268
143268
153466
163565
173664
183862
193961
204060
214159
224357
234555
244654
254852
264951
274951
285149
295149
305248
315347

Chance of precipitation in July

Any precipitation

Isahaya gets around 346 mm of rain over 16.6 wet days in July. The line is the day-by-day chance of measurable precipitation.

Day to day, the chance of measurable rain averages around 53% and peaks near 72% on the wettest days. The odds ease toward the end of the month.

0%20%40%60%80%151015202531
Rain chance (%)
172
271
370
469
568
667
765
864
962
1060
1159
1257
1355
1454
1552
1651
1750
1849
1948
2047
2146
2245
2344
2443
2543
2642
2741
2841
2940
3040
3140

Humidity in July

DryComfortableHumidMuggyOppressiveMiserable

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

By dew point, July lands in the oppressive band about 48% of days. Sticky, muggy-or-worse air turns up on roughly 99% of them.

0%25%50%75%100%151015202531
Humid (%)Muggy (%)Oppressive (%)Miserable (%)
13266011
22246113
32226115
42206117
51186219
61176121
71156024
81145926
91135828
101125631
110115633
120105535
13095338
14095140
15085042
16074844
17074747
18064549
19064450
20054352
21054154
22044056
23043957
24033859
25033760
26033661
27023563
28023464
29023365
30023365
31023266

Wind in July

Winds average 13 km/h in July.

Across July, daily wind ranges from about 12 km/h on the calmest days to 14 km/h at its breeziest. It stays fairly steady from day to day.

05101520151015202531
Wind speed (km/h)Feels
114light breeze
214light breeze
314light breeze
414light breeze
514light breeze
614light breeze
714light breeze
814light breeze
914light breeze
1014light breeze
1114light breeze
1214light breeze
1314light breeze
1414light breeze
1514light breeze
1613light breeze
1713light breeze
1813light breeze
1913light breeze
2013light breeze
2113light breeze
2213light breeze
2312light breeze
2412light breeze
2512light breeze
2612light breeze
2712light breeze
2812light breeze
2912light breeze
3012light breeze
3112light breeze

Sunrise & sunset in July

DaylightNight

Daylight runs from about 14 h 06 min at the start of July to 13 h 42 min by month's end. The lit band spans sunrise to sunset each day.

Days shrink by about 24 minutes over July. Sunrise moves from 5:19 AM to 5:36 AM, and sunset from 7:27 PM to 7:16 PM.

12 AM4 AM8 AM12 PM4 PM8 PM12 AM151015202531
Daylight (h)Sunrise (AM)Sunset (PM)
114.15:197:27
214.15:197:27
314.15:207:27
414.15:207:27
514.15:217:27
614.15:217:27
714.15:227:27
814.15:227:27
914.15:237:27
1014.15:237:26
1114.05:247:26
1214.05:247:26
1314.05:257:26
1414.05:257:25
1514.05:267:25
1614.05:267:25
1714.05:277:24
1813.95:287:24
1913.95:287:23
2013.95:297:23
2113.95:297:22
2213.95:307:22
2313.85:317:21
2413.85:317:21
2513.85:327:20
2613.85:337:19
2713.85:337:19
2813.75:347:18
2913.75:357:17
3013.75:357:17
3113.75:367:16

Solar energy in July

Daily solar energy (kWh/m²)

Average shortwave solar energy reaching the ground each day in July, about 5.02 kWh/m².

For context, solar energy here swings from a low near 2.17 kWh/m² to a high of 5.36 kWh/m² in May across the year — July's 5.02 kWh/m² falls in the middle.

0246151015202531
Solar energy (kWh/m²)Level
14.1Bright
24.2Bright
34.2Bright
44.3Bright
54.3Bright
64.4Bright
74.5Bright
84.5Bright
94.6Bright
104.7Bright
114.7Bright
124.8Bright
134.9Bright
145.0Bright
155.0Bright
165.1Bright
175.2Bright
185.2Bright
195.3Bright
205.3Bright
215.4Bright
225.4Bright
235.4Bright
245.5Bright
255.5Bright
265.5Bright
275.5Bright
285.5Bright
295.5Bright
305.5Bright
315.5Bright
Planning a trip in July

Hazard calendar for Isahaya

In seasonPeak

In July, Isahaya sits inside its pacific typhoon and rainy season season. The full year is below, with each hazard's peak months called out.

Isahaya sits in the Pacific typhoon belt; the season peaks July–October.

Isahaya's rainy season runs June–July, when most of the year's rain falls.

Pacific typhoon
Rainy season
Jan
Feb
Mar
Apr
May
Jun
Jul
Aug
Sep
Oct
Nov
Dec

Is July a good time to visit Isahaya?

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

5.3
Sightseeing
6th-best month of the year
5.6
Beach & pool
3rd-best month of the year

July is a reasonable time to visit Isahaya for sightseeing.

What to pack for Isahaya in July

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

In July, Isahaya sees daytime highs around 27°C and nights near 24°C. Pack light clothes and rain gear. Worth having: sun protection. About 17 days see rain.

light clothesrain gearsun protection

Sea temperature near Isahaya in July

The nearest coast averages about 25°C in July — the other half of the beach question. The full-year curve and swim-comfort zones are below.

The sea at the nearest coast (about 25 km away) is warmest in August at about 27°C and coldest in February near 15°C.

It's comfortable for a long swim from May 24 to Nov 24 — about 6.1 months when the water holds above 20°C.

15°20°25°30°JanFebMarAprMayJunJulAugSepOctNovDecbracingcoolrefreshingwarmtropicalcomfortable to swim
Sea temperature (°C)Comfort
Jan16Cool
Feb15Bracing
Mar15Cool
Apr17Cool
May19Cool
Jun22Refreshing
Jul25Warm
Aug27Warm
Sep26Warm
Oct24Refreshing
Nov21Refreshing
Dec18Cool

UV index in Isahaya in July

LowModerateHighVery highExtreme

Clear-sky midday UV in July peaks around 10 (very high — sun protection essential). The full-year curve, shaded by WHO exposure level, is below.

Under clear skies, the midday UV index in Isahaya peaks around July 16 at about 10 (extreme) — sunscreen, a hat and midday shade are essential. It bottoms out near December 21 at about 3 (moderate).

The index reaches 3 or more — the level where the WHO recommends sun protection — in 11 months of the year.

025710JanFebMarAprMayJunJulAugSepOctNovDecModerateHighVery highVery highModerateJul 16UV 10Dec 21UV 3
UV index (midday)Level
Jan3Moderate
Feb4Moderate
Mar6High
Apr8Very high
May8Very high
Jun9Very high
Jul10Extreme
Aug9Very high
Sep9Very high
Oct7High
Nov4Moderate
Dec3Moderate

Air quality in Isahaya in July

GoodModeratePoorUnhealthyVery unhealthy

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

Air quality in Isahaya is worst in April — around 24 µg/m³ PM2.5 (moderate), about 2.1× the cleanest month (October, 11 µg/m³).

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

0102030JanFebMarAprMayJunJulAugSepOctNovDecModerateModerateGoodModerateApr 1324 µg/m³Oct 1212 µg/m³
PM2.5 (µg/m³)Level
Jan16Moderate
Feb19Moderate
Mar23Moderate
Apr24Moderate
May21Moderate
Jun17Moderate
Jul12Good
Aug12Moderate
Sep12Good
Oct11Good
Nov14Moderate
Dec13Moderate
Location & terrain

Where is Isahaya?

Isahaya sits at 32.8°N, 130.0°E, 104 m above sea level, in Japan. The nearest listed city is Ōmura, 12 km away.

Topography around Isahaya

How much the land rises and falls, and what covers it, within 3, 16 and 80 km of Isahaya.

Within 3 km, the terrain around Isahaya has only modest variations in elevation — a maximum elevation change of 166 m around an average of 37 m above sea level; within 16 km, large variations in elevation — a maximum elevation change of 1,042 m; within 80 km, very significant variations in elevation — a maximum elevation change of 1,455 m.

The land around Isahaya is covered by artificial surfaces (44%) and trees (39%) within 3 km, trees (46%) and water (33%) within 16 km, and water (50%) and trees (37%) within 80 km.

3 km
166 m
16 km
1,042 m
80 km
1,455 m
treesgrasslandcroplandartificial surfacesbare terrainwater
July weather nearby: Ōmura 12 km · Obita 15 km · Nagasaki 18 km · Togitsu 18 km · Unzen 21 km · Minamishimabara 28 km · Kashima 30 km · Ureshinomachi-shimojuku 31 km

Japan travel facts

Travel advisory
Level 1
Exercise Normal Precautions
Power plugs
Type A / B
100 V · 50 / 60 Hz
Prices
≈ 65% of US
price level, 2025
GDP per capita
$35,951
2025
Happiness
6.1 / 10
World Happiness, 2025
Safe drinking water
99%
of population, 2024
Homicide rate
0.2
per 100k, 2023
Road deaths
3.6
per 100k/yr, 2019
Income group
High
World Bank
English
Very low
EF EPI 446
Religion
Shintoism 49%Buddhism 46%other 4%Christianity 1%

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 Isahaya (32.8411°, 130.0431°, elevation 104 m), 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).