St. Catharines weather in July

In July, St. Catharines sees average daytime highs of 25°C and overnight lows near 20°C, with 88 mm of rain across 10.8 wet days and about 14.9 hours of daylight. It is the 1st-warmest and 4th-wettest month of the year here.

Day-to-day highs hold fairly steady near 25°C through the month. The sky is clear or mostly clear about 38% of the time in July, and the air most often feels humid.

Daylight stretches from about 15 h 12 min at the start of July to 14 h 24 min by month's end. Set against the rest of the year, July is St. Catharines's 2nd-clearest and 12th-windiest month. For the whole year in context, see St. Catharines's year-round climate.

Daytime high
25°
1st warmest
Overnight low
20°
12th coldest
Rainfall
88 mm
10.8 wet days
Daylight
14 h 54 min
4:56 AM – 7:50 PM
Cloud cover
52%
2nd clearest
Wind
12 km/h
12th windiest
Solar energy
6.15 kWh/m²
Travel score
6.9
out of 10

St. Catharines is city in Ontario, Canada.

Air quality
Good
PM2.5 7 µg/m³ · 2019
Density
1,410/km²
people per km²
Founded
1783

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

Temperature in July

Average highAverage lowShaded bands: 10–90% of days

Day-to-day highs hold fairly steady near 25°C through the month.

A typical July day in St. Catharines reaches about 25°C in the afternoon and slips back to 20°C overnight — a 5°C spread between the day's warmth and the night's chill. On most days the high lands between 21°C and 28°C. Set against its neighbours, July runs about 3°C warmer than June and on par with August.

15°20°25°30°151015202531
Avg high (°C)Avg low (°C)
12418
22419
32419
42419
52419
62419
72419
82419
92419
102419
112519
122519
132520
142520
152520
162520
172520
182520
192520
202520
212520
222520
232520
242520
252520
262520
272520
282520
292520
302520
312520

How July really feels in St. Catharines

Once humidity and wind are folded in, July averages 0 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
0
heat index over the day's high
Days feeling ≤ C
0
wind chill below the day's low

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

St. Catharines weather by month

How July compares with the rest of the year at a glance. July is the 1st-warmest and 4th-wettest month here — the current month is highlighted below.

MonthHigh / Low (°C)Rainfall (mm)Wet daysSnow daysDaylight (hours)Travel score
Jan-0° / -5°7511.999.20.0
Feb-0° / -6°599710.20.0
Mar / -2°7310.44.611.60.1
Apr / 9711.71.813.11.8
May15° / 10°8311.4014.44.5
Jun21° / 16°9111.1015.16.4
Jul25° / 20°8810.8014.96.9
Aug24° / 19°759.9013.87.1
Sep21° / 16°859.8012.36.5
Oct14° / 9212.10.110.84.1
Nov / 8210.829.51.3
Dec / -1°7711.66.68.90.0

Cloud cover in July

ClearMostly clearPartly cloudyMostly cloudyOvercast

The sky is clear or mostly clear about 38% of the time in July.

Beyond those clear spells, partly cloudy skies cover about 21% of July, with mostly cloudy or overcast conditions the remaining 41%.

0%25%50%75%100%151015202531
Clearer (%)Cloudier (%)
15941
25941
35941
45941
56139
66139
76139
86139
96040
106040
116040
125941
135941
145842
155941
165842
175842
185842
195743
205743
215743
225743
235743
245743
255743
265842
275842
285941
295941
305941
316040

Chance of precipitation in July

Any precipitation

St. Catharines gets around 88 mm of rain over 10.8 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 35% and peaks near 38% on the wettest days.

0%10%20%30%40%50%151015202531
Rain chance (%)
136
236
335
434
534
633
733
832
932
1033
1133
1233
1334
1434
1535
1635
1735
1836
1936
2037
2137
2238
2338
2438
2538
2638
2738
2837
2937
3037
3136

Humidity in July

DryComfortableHumidMuggyOppressiveMiserable

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

By dew point, July lands in the humid band about 33% of days. Sticky, muggy-or-worse air turns up on roughly 37% of them.

0%25%50%75%100%151015202531
Dry (%)Comfortable (%)Humid (%)Muggy (%)Oppressive (%)
1172630244
2162630244
3162630245
4152530245
5152531246
6142531246
7132531247
8132432247
9122432258
10112333258
11112233269
12102133269
13102134279
1492034279
15919342810
16918342910
17918352910
18817343010
19817343110
20816343110
21816343210
22816343210
23816343210
24816343310
25716343310
26716343310
2771634339
2871634339
2971734339
3081733339
3181833329

Wind in July

Winds average 12 km/h in July, the calmest month.

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

051015151015202531
Wind speed (km/h)Feels
112light breeze
212light breeze
312light breeze
412light breeze
512light breeze
612light breeze
712calm
812calm
912calm
1012calm
1112calm
1212calm
1312calm
1412calm
1512calm
1612calm
1712calm
1812calm
1912calm
2012calm
2112calm
2212calm
2312calm
2412calm
2512calm
2612calm
2712calm
2812calm
2912calm
3012calm
3112calm

Sunrise & sunset in July

DaylightNight

Daylight runs from about 15 h 12 min at the start of July to 14 h 24 min by month's end. The lit band spans sunrise to sunset each day.

Days shrink by about 48 minutes over July. Sunrise moves from 4:46 AM to 5:10 AM, and sunset from 7:55 PM to 7:36 PM.

12 AM4 AM8 AM12 PM4 PM8 PM12 AM151015202531
Daylight (h)Sunrise (AM)Sunset (PM)
115.24:467:55
215.14:467:55
315.14:477:55
415.14:477:55
515.14:487:54
615.14:487:54
715.14:497:54
815.14:507:54
915.04:507:53
1015.04:517:53
1115.04:527:52
1215.04:527:52
1315.04:537:51
1414.94:547:51
1514.94:557:50
1614.94:567:50
1714.94:567:49
1814.84:577:48
1914.84:587:47
2014.84:597:47
2114.85:007:46
2214.75:017:45
2314.75:027:44
2414.75:037:43
2514.65:047:42
2614.65:057:41
2714.65:067:40
2814.55:077:39
2914.55:087:38
3014.55:097:37
3114.45:107:36

Solar energy in July

Daily solar energy (kWh/m²)

Average shortwave solar energy reaching the ground each day in July, about 6.15 kWh/m².

For context, solar energy here swings from a low near 1.28 kWh/m² to a high of 6.32 kWh/m² in June across the year — July's 6.15 kWh/m² sits near the top of that range.

0246151015202531
Solar energy (kWh/m²)Level
16.4Intense
26.4Intense
36.4Intense
46.4Intense
56.4Intense
66.3Intense
76.3Intense
86.3Intense
96.3Intense
106.3Intense
116.3Intense
126.2Intense
136.2Intense
146.2Intense
156.2Intense
166.1Intense
176.1Intense
186.1Intense
196.1Intense
206.0Intense
216.0Intense
226.0Bright
236.0Bright
245.9Bright
255.9Bright
265.9Bright
275.9Bright
285.9Bright
295.8Bright
305.8Bright
315.8Bright
Planning a trip in July

Is July a good time to visit St. Catharines?

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

6.9
Sightseeing
2nd-best month of the year
6.0
Beach & pool
2nd-best month of the year

July is a reasonable time to visit St. Catharines for sightseeing. The water and warmth also suit a beach or pool day.

What to pack for St. Catharines in July

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

In July, St. Catharines sees daytime highs around 25°C and nights near 20°C. Pack sun protection. Worth having: light clothes and rain gear. About 11 days see rain.

sun protectionlight clothesrain gear

Sea temperature near St. Catharines in July

The nearest coast averages about 20°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 22°C and coldest in February near 3°C.

It's comfortable for a long swim from Jul 17 to Sep 6 — about 1.7 months when the water holds above 20°C.

0°10°20°JanFebMarAprMayJunJulAugSepOctNovDecbracingcoolrefreshingwarmcomfortable to swim
Sea temperature (°C)Comfort
Jan4Bracing
Feb3Bracing
Mar3Bracing
Apr4Bracing
May7Bracing
Jun15Bracing
Jul20Refreshing
Aug22Refreshing
Sep19Cool
Oct13Bracing
Nov8Bracing
Dec5Bracing

UV index in St. Catharines in July

LowModerateHighVery highExtreme

Clear-sky midday UV in July 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 St. Catharines peaks around June 19 at about 8 (very high) — sunscreen and a hat are worth it in the middle of the day. It bottoms out near December 21 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 highHighModerateLowJun 19UV 8Dec 21UV 1
UV index (midday)Level
Jan1Low
Feb2Moderate
Mar4Moderate
Apr5High
May6High
Jun8Very high
Jul7Very high
Aug6High
Sep5High
Oct3Moderate
Nov2Low
Dec1Low
Location & terrain

Where is St. Catharines?

St. Catharines sits at 43.2°N, 79.2°W, 102 m above sea level, in Canada. The nearest listed city is Thorold, 7.0 km away.

Topography around St. Catharines

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

Within 3 km, the terrain around St. Catharines has only modest variations in elevation — a maximum elevation change of 47 m around an average of 100 m above sea level; within 16 km, only modest variations in elevation — a maximum elevation change of 193 m; within 80 km, significant variations in elevation — a maximum elevation change of 483 m.

The land around St. Catharines is covered by artificial surfaces (51%) and trees (33%) within 3 km, water (33%) and trees (20%) within 16 km, and water (41%) and trees (24%) within 80 km.

3 km
47 m
16 km
193 m
80 km
483 m
treesgrasslandcroplandartificial surfaceswater
July weather nearby: Thorold 7.0 km · Niagara-on-the-Lake 16 km · Niagara Falls 16 km · Niagara Falls 17 km · Welland 21 km · Grimsby 26 km · Grand Island 27 km · Port Colborne 30 km

Canada travel facts

Travel advisory
Level 1
Exercise Normal Precautions
Power plugs
Type A / B
120 V · 60 Hz
Prices
≈ 83% of US
price level, 2025
GDP per capita
$55,698
2025
Happiness
6.7 / 10
World Happiness, 2025
Safe drinking water
97%
of population, 2024
Homicide rate
2
per 100k, 2023
Road deaths
5.3
per 100k/yr, 2019
Income group
High
World Bank
Religion
Christian 53%none 35%Muslim 5%Hindu 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 St. Catharines (43.1713°, -79.2427°, elevation 102 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. 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. Topography is sampled from the Copernicus DEM GLO-90 elevation model (© ESA/Airbus) and ESA WorldCover 2021 land cover (CC BY 4.0).