Lafayette weather in September

In September, Lafayette sees average daytime highs of 88°F and overnight lows near 70°F, with 3.8 in of rain across 11.2 wet days and about 12.2 hours of daylight. It is the 4th-warmest and 9th-wettest month of the year here.

Highs ease over the month, from about 89°F in the first days to 85°F by the end. The sky is clear or mostly clear about 42% of the time in September, and the air most often feels oppressive.

Daylight stretches from about 12 h 36 min at the start of September to 11 h 42 min by month's end. Set against the rest of the year, September is Lafayette's 3rd-clearest and 9th-windiest month. For the whole year in context, see Lafayette's year-round climate.

Daytime high
88°
4th warmest
Overnight low
70°
9th coldest
Rainfall
3.8 in
11.2 wet days
Daylight
12 h 12 min
5:57 AM – 6:08 PM
Cloud cover
51%
3rd clearest
Wind
6 mph
9th windiest
Solar energy
4.98 kWh/m²
Travel score
4.5
out of 10

Lafayette is city in Lafayette Parish, Louisiana, United States.

Density
950/km²
people per km²
Founded
1821

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 89°F in the first days to 85°F by the end.

A typical September day in Lafayette reaches about 88°F in the afternoon and slips back to 70°F overnight — a 17°F spread between the day's warmth and the night's chill. On most days the high lands between 81°F and 93°F. Set against its neighbours, September runs about 3°F cooler than August and about 7°F warmer than October.

50°60°70°80°90°151015202530
Avg high (°F)Avg low (°F)
19073
28973
38973
48973
58973
68972
78972
88972
98972
108972
118972
128871
138871
148871
158871
168871
178870
188770
198770
208769
218769
228769
238669
248668
258668
268667
278567
288567
298566
308566

How September really feels in Lafayette

Once humidity and wind are folded in, September averages 21 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
21
heat index over the day's high
Days feeling ≤ 32°F
0
wind chill below the day's low

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

Lafayette weather by month

How September compares with the rest of the year at a glance. September is the 4th-warmest and 9th-wettest month here — the current month is highlighted below.

MonthHigh / Low (°F)Rainfall (inches)Wet daysDaylight (hours)Travel score
Jan62° / 44°5.09.510.35.4
Feb65° / 47°4.28.810.96.0
Mar72° / 53°4.310.111.86.7
Apr78° / 59°4.39.112.77.0
May85° / 67°3.69.713.55.5
Jun89° / 73°4.514.213.93.7
Jul90° / 75°4.917.513.83.2
Aug91° / 74°4.816.113.13.2
Sep88° / 70°3.811.212.24.5
Oct80° / 60°3.87.711.37.0
Nov71° / 51°3.58.210.57.1
Dec64° / 46°4.69.210.15.9

Cloud cover in September

ClearMostly clearPartly cloudyMostly cloudyOvercast

The sky is clear or mostly clear about 42% of the time in September.

Beyond those clear spells, partly cloudy skies cover about 18% of September, with mostly cloudy or overcast conditions the remaining 40%. Skies tend to open up as the month goes on.

0%25%50%75%100%151015202530
Clearer (%)Cloudier (%)
15149
25149
35248
45347
55347
65446
75545
85644
95743
105842
115842
125941
136040
146040
156139
166139
176139
186238
196238
206337
216436
226436
236535
246634
256733
266733
276733
286832
296832
306832

Chance of precipitation in September

Any precipitation

Lafayette gets around 3.8 in of rain over 11.2 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 37% and peaks near 49% on the wettest days. The odds ease toward the end of the month.

0%20%40%60%151015202530
Rain chance (%)
149
249
348
448
547
646
745
845
944
1043
1142
1241
1340
1440
1539
1638
1737
1836
1935
2034
2132
2231
2330
2429
2528
2627
2726
2825
2925
3024

Humidity in September

DryComfortableHumidMuggyOppressiveMiserable

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

By dew point, September lands in the oppressive band about 46% of days. Sticky, muggy-or-worse air turns up on roughly 77% of them.

0%25%50%75%100%151015202530
Dry (%)Comfortable (%)Humid (%)Muggy (%)Oppressive (%)Miserable (%)
1136166014
2137166013
3147175813
4147175912
5148175911
6158185810
7258185710
825819579
925819579
1026920549
1126920558
1236921538
1336922528
1436922528
15461023508
16461024488
17561024478
18661125458
19761125438
20871126418
21971126397
221171226387
231271226367
241381326346
251581326336
261681426325
271781426305
281891425294
291991525284
3020101525273

Wind in September

Winds average 6 mph in September.

Across September, daily wind ranges from about 5 mph on the calmest days to 7 mph at its breeziest. It stays fairly steady from day to day.

0246810151015202530
Wind speed (mph)Feels
15calm
26calm
36calm
46calm
56calm
66calm
76calm
86calm
96calm
106calm
116calm
126calm
136calm
146calm
156calm
166calm
176calm
186calm
196calm
206calm
216calm
226calm
236calm
246calm
256calm
266calm
276calm
286calm
297calm
307calm

Sunrise & sunset in September

DaylightNight

Daylight runs from about 12 h 36 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 54 minutes over September. Sunrise moves from 5:49 AM to 6:05 AM, and sunset from 6:27 PM to 5:50 PM.

12 AM4 AM8 AM12 PM4 PM8 PM12 AM151015202530
Daylight (h)Sunrise (AM)Sunset (PM)
112.65:496:27
212.65:496:26
312.65:506:25
412.65:506:23
512.55:516:22
612.55:516:21
712.55:526:19
812.45:526:18
912.45:536:17
1012.45:546:16
1112.35:546:14
1212.35:556:13
1312.35:556:12
1412.25:566:10
1512.25:566:09
1612.25:576:08
1712.15:586:06
1812.15:586:05
1912.15:596:04
2012.15:596:03
2112.06:006:01
2212.06:006:00
2312.06:015:59
2411.96:025:57
2511.96:025:56
2611.96:035:55
2711.86:035:53
2811.86:045:52
2911.86:055:51
3011.76:055:50

Solar energy in September

Daily solar energy (kWh/m²)

Average shortwave solar energy reaching the ground each day in September, about 4.98 kWh/m².

For context, solar energy here swings from a low near 2.67 kWh/m² to a high of 6.18 kWh/m² in May across the year — September's 4.98 kWh/m² falls in the middle.

0246151015202530
Solar energy (kWh/m²)Level
15.2Bright
25.2Bright
35.2Bright
45.2Bright
55.1Bright
65.1Bright
75.1Bright
85.1Bright
95.1Bright
105.0Bright
115.0Bright
125.0Bright
135.0Bright
145.0Bright
155.0Bright
164.9Bright
174.9Bright
184.9Bright
194.9Bright
204.9Bright
214.9Bright
224.8Bright
234.8Bright
244.8Bright
254.8Bright
264.8Bright
274.8Bright
284.8Bright
294.8Bright
304.8Bright
Planning a trip in September

Hazard calendar for Lafayette

In seasonPeak

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

Lafayette 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 September a good time to visit Lafayette?

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

4.5
Sightseeing
9th-best month of the year
6.6
Beach & pool
3rd-best month of the year

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

What to pack for Lafayette in September

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

In September, Lafayette sees daytime highs around 88°F and nights near 70°F. Pack light clothes. Worth having: rain gear and sun protection. About 11 days see rain.

light clothesrain gearsun protection

Sea temperature near Lafayette in September

The nearest coast averages about 83°F in September — the other half of the beach question. The full-year curve and swim-comfort zones are below.

The sea at the nearest coast (about 42 mi away) is warmest in August at about 86°F and coldest in January near 58°F.

It's comfortable for a long swim from Mar 30 to Nov 15 — about 7.6 months when the water holds above 68°F.

60°70°80°90°JanFebMarAprMayJunJulAugSepOctNovDecbracingcoolrefreshingwarmtropicalcomfortable to swim
Sea temperature (°F)Comfort
Jan58Bracing
Feb60Cool
Mar65Cool
Apr72Refreshing
May78Warm
Jun84Tropical
Jul86Tropical
Aug86Tropical
Sep83Tropical
Oct76Warm
Nov68Cool
Dec62Cool

UV index in Lafayette in September

LowModerateHighVery highExtreme

Clear-sky midday UV in September peaks around 8 (very high — sun protection essential). The full-year curve, shaded by WHO exposure level, is below.

Under clear skies, the midday UV index in Lafayette peaks around July 13 at about 10 (extreme) — sunscreen, a hat and midday shade are essential. It bottoms out near December 20 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 highExtremeVery highHighModerateJul 13UV 10Dec 20UV 4
UV index (midday)Level
Jan4Moderate
Feb6High
Mar7High
Apr10Extreme
May10Very high
Jun10Very high
Jul10Extreme
Aug9Very high
Sep8Very high
Oct6High
Nov5Moderate
Dec4Moderate

Air quality in Lafayette 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 Lafayette is worst in July — around 22 µg/m³ PM2.5 (moderate), about 2.7× the cleanest month (December, 8 µg/m³).

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

0102030JanFebMarAprMayJunJulAugSepOctNovDecModerateGoodModerateGoodGoodJul 1521 µg/m³Dec 169 µg/m³
PM2.5 (µg/m³)Level
Jan14Moderate
Feb13Moderate
Mar11Good
Apr11Good
May14Moderate
Jun18Moderate
Jul22Moderate
Aug16Moderate
Sep12Moderate
Oct9Good
Nov13Moderate
Dec8Good
Location & terrain

Where is Lafayette?

Lafayette sits at 30.2°N, 92.0°W, 36 ft above sea level, in United States. The nearest listed city is New Iberia, 19 mi away.

Topography around Lafayette

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

Within 2 miles, the terrain around Lafayette has only modest variations in elevation — a maximum elevation change of 85 ft around an average of 43 ft above sea level; within 10 miles, only modest variations in elevation — a maximum elevation change of 121 ft; within 50 miles, only modest variations in elevation — a maximum elevation change of 233 ft.

The land around Lafayette is covered by trees (41%) and artificial surfaces (41%) within 2 miles, trees (40%) and grassland (37%) within 10 miles, and trees (38%) and cropland (26%) within 50 miles.

2 miles
85 ft
10 miles
121 ft
50 miles
233 ft
treesgrasslandcroplandartificial surfacesbare terrainwaterwetland
September weather nearby: New Iberia 19 mi · Opelousas 22 mi · Baton Rouge 52 mi · Zachary 59 mi · Shenandoah 62 mi · Prairieville 63 mi · Central 63 mi · Lake Charles 71 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 Lafayette (30.2241°, -92.0198°, elevation 36 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).