Slidell in Summer

In summer (June, July and August), Slidell sees average daytime highs around 86°F and overnight lows near 77°F, with 15.8 in of rain over about 51 wet days across the season. It is the warmest season of the year and the wettest season of the year.

Across summer, daytime highs hold fairly steady around 86°F. The sky is clear or mostly clear about 33% of the time across summer, and the air most often feels miserable.

Summer is Slidell's weakest season of the year to visit on our travel score. For the whole year in context, see Slidell's year-round climate.

Avg daytime high
86°F
warmest season of the year
Avg overnight low
77°F
Rainfall
15.8 in
51 wet days
Avg wind
6 mph
Travel score
4.2
weakest season of the year
Months
Jun · Jul · Aug

Temperature in Slidell in Summer

Average highAverage lowShaded bands: 10–90% of days

Across summer, daytime highs hold fairly steady around 86°F.

A typical summer day in Slidell reaches about 86°F and drops to 77°F overnight. The warmest of the three months is July, the coolest June.

70°80°90°JunJulAug

How summer really feels in Slidell

Once humidity and wind are folded in, summer brings about 87 days that feel above 90°F and 0 that feel at or below 32°F.

Days feeling ≥ 90°F
87
heat index over the day's high
Days feeling ≤ 32°F
0
wind chill below the day's low

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

Slidell weather by month

How the three summer months (June, July and August) compare with the rest of the year — the season's months are highlighted.

MonthHigh / Low (°F)Rainfall (inches)Wet daysDaylight (hours)Travel score
Jan59° / 47°4.59.310.34.6
Feb62° / 51°4.48.710.95.4
Mar67° / 56°4.89.211.86.5
Apr73° / 63°3.88.712.77.1
May80° / 71°3.59.913.56.8
Jun85° / 76°4.91513.94.7
Jul87° / 78°5.118.113.84.0
Aug87° / 78°5.917.913.14.0
Sep83° / 74°4.712.512.25.5
Oct76° / 65°3.47.611.37.5
Nov67° / 55°3.3710.56.9
Dec61° / 50°4.09.110.15.2

Cloud cover in Summer

ClearMostly clearPartly cloudyMostly cloudyOvercast

The sky is clear or mostly clear about 33% of the time across summer.

0%25%50%75%100%JunJulAug

Chance of precipitation in Summer

Any precipitation

Slidell gets around 15.8 in of rain over 51 wet days across summer. The line is the day-by-day chance of measurable precipitation.

0%20%40%60%JunJulAug

Humidity in Summer

DryComfortableHumidMuggyOppressiveMiserable

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

0%25%50%75%100%JunJulAug

Wind in Summer

Winds average 6 mph across summer.

0246810JunJulAug

Sunrise & sunset in Summer

DaylightNight

Daylight runs from about 13 h 48 min in early June to 12 h 42 min by late August. The lit band spans sunrise to sunset each day.

12 AM4 AM8 AM12 PM4 PM8 PM12 AMJunJulAug

Solar energy in Summer

Daily solar energy (kWh/m²)

Average shortwave solar energy reaching the ground each day across summer, about 5.8 kWh/m².

0246JunJulAug
Planning a trip in summer

Hazard calendar for Slidell

In seasonPeak

In summer, Slidell overlaps its atlantic hurricane season. The full year is below, with each hazard's peak months called out.

Slidell 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 summer a good time to visit Slidell?

Our two travel scores rate summer for general sightseeing and for beach or pool weather — 0 (poor) to 10 (ideal), averaged across the three months.

4.2
Sightseeing
4th-best month of the year
5.8
Beach & pool
1st-best month of the year

summer is a reasonable time to visit Slidell for sightseeing.

What to pack for Slidell in Summer

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

In summer, Slidell sees daytime highs around 86°F and nights near 77°F. Pack light clothes, rain gear and sun protection. About 51 days see rain.

light clothesrain gearsun protection

Sea temperature near Slidell in Summer

The nearest coast averages about 85°F across summer — the other half of the beach question. The full-year curve and swim-comfort zones are below.

The sea at the nearest coast (about 12 mi away) is warmest in August at about 86°F and coldest in January near 57°F.

It's comfortable for a long swim from Apr 5 to Nov 10 — about 7.2 months when the water holds above 68°F.

50°60°70°80°90°JanFebMarAprMayJunJulAugSepOctNovDecbracingcoolrefreshingwarmtropicalcomfortable to swim
Sea temperature (°F)Comfort
Jan57Bracing
Feb58Bracing
Mar64Cool
Apr71Refreshing
May78Warm
Jun84Tropical
Jul86Tropical
Aug86Tropical
Sep83Tropical
Oct75Warm
Nov67Cool
Dec60Cool

UV index in Slidell in Summer

LowModerateHighVery highExtreme

Clear-sky midday UV across summer averages 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 Slidell peaks around July 12 at about 10 (extreme) — sunscreen, a hat and midday shade are essential. It bottoms out near December 19 at about 4 (moderate).

The index reaches 3 or more — the level where the WHO recommends sun protection — every month of the year.

025710JanFebMarAprMayJunJulAugSepOctNovDecModerateHighVery highVery highHighModerateJul 12UV 10Dec 19UV 4
UV index (midday)Level
Jan4Moderate
Feb6High
Mar6High
Apr10Very high
May10Very high
Jun10Very high
Jul10Extreme
Aug9Very high
Sep8Very high
Oct6High
Nov5Moderate
Dec4Moderate

Air quality in Slidell in Summer

GoodModeratePoorUnhealthyVery unhealthy

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

Air quality in Slidell is worst in July — around 22 µg/m³ PM2.5 (moderate), about 2.9× the cleanest month (November, 8 µg/m³).

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

0102030JanFebMarAprMayJunJulAugSepOctNovDecGoodModerateGoodJul 1621 µg/m³Nov 238 µg/m³
PM2.5 (µg/m³)Level
Jan8Good
Feb9Good
Mar10Good
Apr10Good
May13Moderate
Jun18Moderate
Jul22Moderate
Aug17Moderate
Sep11Good
Oct8Good
Nov8Good
Dec8Good
Location & terrain

Where is Slidell?

Slidell sits at 30.3°N, 89.8°W, 3 ft above sea level, in United States. The nearest listed city is Chalmette, 25 mi away.

Topography around Slidell

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

Within 2 miles, the terrain around Slidell has only modest variations in elevation — a maximum elevation change of 62 ft around an average of 16 ft above sea level; within 10 miles, only modest variations in elevation — a maximum elevation change of 118 ft; within 50 miles, only modest variations in elevation — a maximum elevation change of 423 ft.

The land around Slidell is covered by trees (56%) and artificial surfaces (25%) within 2 miles, trees (52%) and water (26%) within 10 miles, and trees (44%) and water (34%) within 50 miles.

2 miles
62 ft
10 miles
118 ft
50 miles
423 ft
treesgrasslandartificial surfacesbare terrainwaterwetland
Summer weather nearby: Chalmette 25 mi · New Orleans 28 mi · Terrytown 29 mi · Gretna 30 mi · Metairie 30 mi · Metairie Terrace 30 mi · Harvey 31 mi · Marrero 32 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 Slidell (30.2752°, -89.7812°, elevation 3 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.