Nakhon Sawan weather in September

In September, Nakhon Sawan sees average daytime highs of 33°C and overnight lows near 26°C, with 272 mm of rain across 25.9 wet days and about 12.1 hours of daylight. It is the 8th-warmest and 1st-wettest month of the year here.

Day-to-day highs hold fairly steady near 33°C through the month. The sky is clear or mostly clear about 5% of the time in September, and the air most often feels miserable.

Daylight stretches from about 12 h 18 min at the start of September to 11 h 54 min by month's end. Set against the rest of the year, September is Nakhon Sawan's 9th-clearest and 11th-windiest month. For the whole year in context, see Nakhon Sawan's year-round climate.

Daytime high: 33°; 8th warmest
Overnight low: 26°; 7th coldest
Rainfall: 272 mm; 25.9 wet days
Daylight: 12 h 06 min; 6:11 AM – 6:16 PM
Cloud cover: 83%; 9th clearest
Wind: 5 km/h; 11th windiest
Solar energy: 4.57 kWh/m²
Travel score: 2.0; out of 10

Nakhon Sawan is city in Nakhon Sawan province, Thailand.

Air quality: High; PM2.5 28 µg/m³ · 2019
Density: 2,953/km²; people per km²

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

← August Nakhon Sawan year-round climate October →Best places to visit in September

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

Temperature in September

Average highAverage lowShaded bands: 10–90% of days

Day-to-day highs hold fairly steady near 33°C through the month.

A typical September day in Nakhon Sawan reaches about 33°C in the afternoon and slips back to 26°C overnight — a 7°C spread between the day's warmth and the night's chill. On most days the high lands between 31°C and 35°C. Set against its neighbours, September runs on par with August and on par with October.

	1	2	3	4	5	6	7	8	9	10	11	12	13	14	15	16	17	18	19	20	21	22	23	24	25	26	27	28	29	30
Avg high (°C)	33	33	33	33	33	33	33	33	33	33	33	33	33	33	33	33	33	33	33	33	33	33	33	33	33	33	33	33	33	33
Avg low (°C)	26	26	26	26	26	26	26	26	26	26	26	26	26	26	26	26	26	26	26	26	26	26	26	26	26	26	26	26	26	26

	Avg high (°C)	Avg low (°C)
1	33	26
2	33	26
3	33	26
4	33	26
5	33	26
6	33	26
7	33	26
8	33	26
9	33	26
10	33	26
11	33	26
12	33	26
13	33	26
14	33	26
15	33	26
16	33	26
17	33	26
18	33	26
19	33	26
20	33	26
21	33	26
22	33	26
23	33	26
24	33	26
25	33	26
26	33	26
27	33	26
28	33	26
29	33	26
30	33	26

How September really feels in Nakhon Sawan

Once humidity and wind are folded in, September averages 30 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

30 feel dangerously hot (≥ 39°C)

Days feeling ≤ 0°C

wind chill below the day's low

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

Nakhon Sawan weather by month

How September compares with the rest of the year at a glance. September is the 8th-warmest and 1st-wettest month here — the current month is highlighted below.

Month	High / Low (°C)	Rainfall (mm)	Wet days	Daylight (hours)	Travel score
Jan	33° / 21°	10	2	11.2	4.6
Feb	35° / 23°	11	2	11.5	3.2
Mar	37° / 25°	38	6.2	11.9	1.8
Apr	38° / 27°	62	11.4	12.3	1.1
May	36° / 27°	156	21	12.7	1.3
Jun	35° / 27°	147	23.3	12.9	1.5
Jul	35° / 27°	161	23.5	12.8	1.8
Aug	34° / 26°	215	25.1	12.5	1.9
Sep	33° / 26°	272	25.9	12.1	2.0
Oct	33° / 25°	143	17.1	11.6	3.1
Nov	32° / 23°	24	4.7	11.3	4.3
Dec	32° / 21°	8	1.2	11.1	5.2

Cloud cover in September

ClearMostly clearPartly cloudyMostly cloudyOvercast

The sky is clear or mostly clear about 5% of the time in September.

Beyond those clear spells, partly cloudy skies cover about 8% of September, with mostly cloudy or overcast conditions the remaining 87%. Skies tend to open up as the month goes on.

	1	2	3	4	5	6	7	8	9	10	11	12	13	14	15	16	17	18	19	20	21	22	23	24	25	26	27	28	29	30
Clearer (%)	5	5	6	6	6	6	7	7	8	9	9	9	11	11	12	12	14	14	16	16	17	18	19	19	21	21	22	23	25	25
Cloudier (%)	95	95	94	94	94	94	93	93	92	91	91	91	89	89	88	88	86	86	84	84	83	82	81	81	79	79	78	77	75	75

	Clearer (%)	Cloudier (%)
1	5	95
2	5	95
3	6	94
4	6	94
5	6	94
6	6	94
7	7	93
8	7	93
9	8	92
10	9	91
11	9	91
12	9	91
13	11	89
14	11	89
15	12	88
16	12	88
17	14	86
18	14	86
19	16	84
20	16	84
21	17	83
22	18	82
23	19	81
24	19	81
25	21	79
26	21	79
27	22	78
28	23	77
29	25	75
30	25	75

Chance of precipitation in September

Any precipitation

Nakhon Sawan gets around 272 mm of rain over 25.9 wet days in September, the wettest month. The line is the day-by-day chance of measurable precipitation.

Day to day, the chance of measurable rain averages around 86% and peaks near 88% on the wettest days.

	1	2	3	4	5	6	7	8	9	10	11	12	13	14	15	16	17	18	19	20	21	22	23	24	25	26	27	28	29	30
Rain chance (%)	87	87	87	87	88	88	88	88	88	87	87	87	87	87	86	86	86	86	86	85	85	85	85	85	85	85	85	84	84	83

	Rain chance (%)
1	87
2	87
3	87
4	87
5	88
6	88
7	88
8	88
9	88
10	87
11	87
12	87
13	87
14	87
15	86
16	86
17	86
18	86
19	86
20	85
21	85
22	85
23	85
24	85
25	85
26	85
27	85
28	84
29	84
30	83

Humidity in September

DryComfortableHumidMuggyOppressiveMiserable

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

By dew point, September lands in the miserable band about 93% of days. Sticky, muggy-or-worse air turns up on roughly 100% of them.

	1	2	3	4	5	6	7	8	9	10	11	12	13	14	15	16	17	18	19	20	21	22	23	24	25	26	27	28	29	30
Oppressive (%)	11	11	10	9	9	8	7	7	6	6	6	5	5	5	5	5	5	5	5	5	6	6	6	7	7	7	8	8	9	9
Miserable (%)	89	89	90	91	91	92	93	93	94	94	94	95	95	95	95	95	95	95	95	95	94	94	94	93	93	93	92	92	91	91

	Oppressive (%)	Miserable (%)
1	11	89
2	11	89
3	10	90
4	9	91
5	9	91
6	8	92
7	7	93
8	7	93
9	6	94
10	6	94
11	6	94
12	5	95
13	5	95
14	5	95
15	5	95
16	5	95
17	5	95
18	5	95
19	5	95
20	5	95
21	6	94
22	6	94
23	6	94
24	7	93
25	7	93
26	7	93
27	8	92
28	8	92
29	9	91
30	9	91

Wind in September

Winds average 5 km/h in September.

Across September, daily wind ranges from about 5 km/h on the calmest days to 6 km/h at its breeziest. It stays fairly steady from day to day.

	1	2	3	4	5	6	7	8	9	10	11	12	13	14	15	16	17	18	19	20	21	22	23	24	25	26	27	28	29	30
Wind speed (km/h)	6	6	6	6	6	6	6	6	6	6	6	6	6	5	5	5	5	5	5	5	5	5	5	5	5	5	5	5	5	5
Feels	calm	calm	calm	calm	calm	calm	calm	calm	calm	calm	calm	calm	calm	calm	calm	calm	calm	calm	calm	calm	calm	calm	calm	calm	calm	calm	calm	calm	calm	calm

	Wind speed (km/h)	Feels
1	6	calm
2	6	calm
3	6	calm
4	6	calm
5	6	calm
6	6	calm
7	6	calm
8	6	calm
9	6	calm
10	6	calm
11	6	calm
12	6	calm
13	6	calm
14	5	calm
15	5	calm
16	5	calm
17	5	calm
18	5	calm
19	5	calm
20	5	calm
21	5	calm
22	5	calm
23	5	calm
24	5	calm
25	5	calm
26	5	calm
27	5	calm
28	5	calm
29	5	calm
30	5	calm

Sunrise & sunset in September

DaylightNight

Daylight runs from about 12 h 18 min at the start of September to 11 h 54 min by month's end. The lit band spans sunrise to sunset each day.

Days shrink by about 24 minutes over September. Sunrise moves from 6:10 AM to 6:12 AM, and sunset from 6:28 PM to 6:05 PM.

	1	2	3	4	5	6	7	8	9	10	11	12	13	14	15	16	17	18	19	20	21	22	23	24	25	26	27	28	29	30
Daylight (h)	12.3	12.3	12.3	12.3	12.3	12.2	12.2	12.2	12.2	12.2	12.2	12.1	12.1	12.1	12.1	12.1	12.1	12.1	12.0	12.0	12.0	12.0	12.0	12.0	12.0	11.9	11.9	11.9	11.9	11.9
Sunrise (AM)	6:10	6:10	6:10	6:10	6:10	6:10	6:10	6:11	6:11	6:11	6:11	6:11	6:11	6:11	6:11	6:11	6:11	6:11	6:11	6:11	6:12	6:12	6:12	6:12	6:12	6:12	6:12	6:12	6:12	6:12
Sunset (PM)	6:28	6:28	6:27	6:26	6:25	6:25	6:24	6:23	6:22	6:21	6:20	6:20	6:19	6:18	6:17	6:16	6:16	6:15	6:14	6:13	6:12	6:11	6:11	6:10	6:09	6:08	6:07	6:07	6:06	6:05

	Daylight (h)	Sunrise (AM)	Sunset (PM)
1	12.3	6:10	6:28
2	12.3	6:10	6:28
3	12.3	6:10	6:27
4	12.3	6:10	6:26
5	12.3	6:10	6:25
6	12.2	6:10	6:25
7	12.2	6:10	6:24
8	12.2	6:11	6:23
9	12.2	6:11	6:22
10	12.2	6:11	6:21
11	12.2	6:11	6:20
12	12.1	6:11	6:20
13	12.1	6:11	6:19
14	12.1	6:11	6:18
15	12.1	6:11	6:17
16	12.1	6:11	6:16
17	12.1	6:11	6:16
18	12.1	6:11	6:15
19	12.0	6:11	6:14
20	12.0	6:11	6:13
21	12.0	6:12	6:12
22	12.0	6:12	6:11
23	12.0	6:12	6:11
24	12.0	6:12	6:10
25	12.0	6:12	6:09
26	11.9	6:12	6:08
27	11.9	6:12	6:07
28	11.9	6:12	6:07
29	11.9	6:12	6:06
30	11.9	6:12	6:05

Solar energy in September

Daily solar energy (kWh/m²)

Average shortwave solar energy reaching the ground each day in September, about 4.57 kWh/m².

For context, solar energy here swings from a low near 4.49 kWh/m² to a high of 6.25 kWh/m² in April across the year — September's 4.57 kWh/m² sits near the bottom.

	1	2	3	4	5	6	7	8	9	10	11	12	13	14	15	16	17	18	19	20	21	22	23	24	25	26	27	28	29	30
Solar energy (kWh/m²)	4.6	4.6	4.6	4.6	4.6	4.6	4.6	4.6	4.6	4.5	4.5	4.5	4.5	4.5	4.5	4.5	4.5	4.5	4.5	4.5	4.5	4.5	4.5	4.5	4.5	4.5	4.5	4.5	4.5	4.5
Level	Bright	Bright	Bright	Bright	Bright	Bright	Bright	Bright	Bright	Bright	Bright	Bright	Bright	Bright	Bright	Bright	Bright	Bright	Bright	Bright	Bright	Bright	Bright	Bright	Bright	Bright	Bright	Bright	Bright	Bright

	Solar energy (kWh/m²)	Level
1	4.6	Bright
2	4.6	Bright
3	4.6	Bright
4	4.6	Bright
5	4.6	Bright
6	4.6	Bright
7	4.6	Bright
8	4.6	Bright
9	4.6	Bright
10	4.5	Bright
11	4.5	Bright
12	4.5	Bright
13	4.5	Bright
14	4.5	Bright
15	4.5	Bright
16	4.5	Bright
17	4.5	Bright
18	4.5	Bright
19	4.5	Bright
20	4.5	Bright
21	4.5	Bright
22	4.5	Bright
23	4.5	Bright
24	4.5	Bright
25	4.5	Bright
26	4.5	Bright
27	4.5	Bright
28	4.5	Bright
29	4.5	Bright
30	4.5	Bright

Planning a trip in September

Hazard calendar for Nakhon Sawan

In seasonPeak

In September, Nakhon Sawan sits inside its pacific typhoon and monsoon season. The full year is below, with each hazard's peak months called out.

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

Nakhon Sawan's monsoon runs May–October, when most of the year's rain falls.

Pacific typhoon

Monsoon

Jan

Feb

Mar

Apr

May

Jun

Jul

Aug

Sep

Oct

Nov

Dec

Is September a good time to visit Nakhon Sawan?

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

2.0

Sightseeing

6th-best month of the year

3.7

Beach & pool

8th-best month of the year

September is a weaker month for outdoor sightseeing in Nakhon Sawan.

What to pack for Nakhon Sawan in September

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

In September, Nakhon Sawan sees daytime highs around 33°C and nights near 26°C. Pack light clothes and rain gear. Worth having: sun protection. About 26 days see rain.

light clothesrain gearsun protection

UV index in Nakhon Sawan in September

LowModerateHighVery highExtreme

Clear-sky midday UV in September peaks around 12 (very high — sun protection essential). The full-year curve, shaded by WHO exposure level, is below.

Under clear skies, the midday UV index in Nakhon Sawan peaks around August 15 at about 13 (extreme) — sunscreen, a hat and midday shade are essential. It bottoms out near December 12 at about 8 (very high).

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

	Jan	Feb	Mar	Apr	May	Jun	Jul	Aug	Sep	Oct	Nov	Dec
UV index (midday)	9	10	12	10	12	12	13	14	12	10	8	8
Level	Very high	Very high	Extreme	Extreme	Extreme	Extreme	Extreme	Extreme	Extreme	Very high	Very high	Very high

	UV index (midday)	Level
Jan	9	Very high
Feb	10	Very high
Mar	12	Extreme
Apr	10	Extreme
May	12	Extreme
Jun	12	Extreme
Jul	13	Extreme
Aug	14	Extreme
Sep	12	Extreme
Oct	10	Very high
Nov	8	Very high
Dec	8	Very high

Air quality in Nakhon Sawan 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 Nakhon Sawan is worst in March — around 41 µg/m³ PM2.5 (poor), about 2.3× the cleanest month (June, 18 µg/m³).

Seasonal pattern from CAMS reanalysis, scaled to Nakhon Sawan's WHO annual average of 28 µg/m³.

	Jan	Feb	Mar	Apr	May	Jun	Jul	Aug	Sep	Oct	Nov	Dec
PM2.5 (µg/m³)	37	39	41	34	25	18	18	19	22	26	27	32
Level	Poor	Poor	Poor	Moderate	Moderate	Moderate	Moderate	Moderate	Moderate	Moderate	Moderate	Moderate

	PM2.5 (µg/m³)	Level
Jan	37	Poor
Feb	39	Poor
Mar	41	Poor
Apr	34	Moderate
May	25	Moderate
Jun	18	Moderate
Jul	18	Moderate
Aug	19	Moderate
Sep	22	Moderate
Oct	26	Moderate
Nov	27	Moderate
Dec	32	Moderate

Location & terrain

Where is Nakhon Sawan?

Nakhon Sawan sits at 15.7°N, 100.1°E, 31 m above sea level, in Thailand. The nearest listed city is Lat Yao, 38 km away.

Topography around Nakhon Sawan

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

Within 3 km, the terrain around Nakhon Sawan has only modest variations in elevation — a maximum elevation change of 150 m around an average of 31 m above sea level; within 16 km, only modest variations in elevation — a maximum elevation change of 194 m; within 80 km, large variations in elevation — a maximum elevation change of 756 m.

The land around Nakhon Sawan is covered by artificial surfaces (37%), trees (26%) and cropland (20%) within 3 km, cropland (61%) within 16 km, and cropland (85%) within 80 km.

3 km

150 m

artificial surfaces 37%

16 km

194 m

cropland 61%

80 km

756 m

cropland 85%

treesgrasslandcroplandartificial surfacesbare terrainwaterwetland

← August Nakhon Sawan year-round climate October →Best places to visit in September

September weather nearby: Lat Yao 38 km · Thap Than 38 km · Uthai Thani 38 km · Bang Mun Nak 44 km · Khanu Woralaksaburi 50 km · Chai Nat 58 km · Taphan Hin 65 km · Thap Khlo 71 km

Thailand travel facts

Travel advisory: Level 1; Exercise Normal Precautions
Power plugs: Type A / B / C; 230 V · 50 Hz
Prices: ≈ 31% of US; price level, 2025
GDP per capita: $8,057; 2025
Happiness: 6.3 / 10; World Happiness, 2025
Homicide rate: 4.8; per 100k, 2011
Road deaths: 32.2; per 100k/yr, 2019
Income group: Upper middle; World Bank
English: Very low; EF EPI 402
Religion

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 Nakhon Sawan (15.7047°, 100.1372°, elevation 31 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). 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).

	Avg high (°C)	Avg low (°C)
1	33	26
2	33	26
3	33	26
4	33	26
5	33	26
6	33	26
7	33	26
8	33	26
9	33	26
10	33	26
11	33	26
12	33	26
13	33	26
14	33	26
15	33	26
16	33	26
17	33	26
18	33	26
19	33	26
20	33	26
21	33	26
22	33	26
23	33	26
24	33	26
25	33	26
26	33	26
27	33	26
28	33	26
29	33	26
30	33	26

	Clearer (%)	Cloudier (%)
1	5	95
2	5	95
3	6	94
4	6	94
5	6	94
6	6	94
7	7	93
8	7	93
9	8	92
10	9	91
11	9	91
12	9	91
13	11	89
14	11	89
15	12	88
16	12	88
17	14	86
18	14	86
19	16	84
20	16	84
21	17	83
22	18	82
23	19	81
24	19	81
25	21	79
26	21	79
27	22	78
28	23	77
29	25	75
30	25	75

	Rain chance (%)
1	87
2	87
3	87
4	87
5	88
6	88
7	88
8	88
9	88
10	87
11	87
12	87
13	87
14	87
15	86
16	86
17	86
18	86
19	86
20	85
21	85
22	85
23	85
24	85
25	85
26	85
27	85
28	84
29	84
30	83

	Oppressive (%)	Miserable (%)
1	11	89
2	11	89
3	10	90
4	9	91
5	9	91
6	8	92
7	7	93
8	7	93
9	6	94
10	6	94
11	6	94
12	5	95
13	5	95
14	5	95
15	5	95
16	5	95
17	5	95
18	5	95
19	5	95
20	5	95
21	6	94
22	6	94
23	6	94
24	7	93
25	7	93
26	7	93
27	8	92
28	8	92
29	9	91
30	9	91

	Avg high (°C)	Avg low (°C)
1	33	26
2	33	26
3	33	26
4	33	26
5	33	26
6	33	26
7	33	26
8	33	26
9	33	26
10	33	26
11	33	26
12	33	26
13	33	26
14	33	26
15	33	26
16	33	26
17	33	26
18	33	26
19	33	26
20	33	26
21	33	26
22	33	26
23	33	26
24	33	26
25	33	26
26	33	26
27	33	26
28	33	26
29	33	26
30	33	26

	Clearer (%)	Cloudier (%)
1	5	95
2	5	95
3	6	94
4	6	94
5	6	94
6	6	94
7	7	93
8	7	93
9	8	92
10	9	91
11	9	91
12	9	91
13	11	89
14	11	89
15	12	88
16	12	88
17	14	86
18	14	86
19	16	84
20	16	84
21	17	83
22	18	82
23	19	81
24	19	81
25	21	79
26	21	79
27	22	78
28	23	77
29	25	75
30	25	75

	Rain chance (%)
1	87
2	87
3	87
4	87
5	88
6	88
7	88
8	88
9	88
10	87
11	87
12	87
13	87
14	87
15	86
16	86
17	86
18	86
19	86
20	85
21	85
22	85
23	85
24	85
25	85
26	85
27	85
28	84
29	84
30	83

	Oppressive (%)	Miserable (%)
1	11	89
2	11	89
3	10	90
4	9	91
5	9	91
6	8	92
7	7	93
8	7	93
9	6	94
10	6	94
11	6	94
12	5	95
13	5	95
14	5	95
15	5	95
16	5	95
17	5	95
18	5	95
19	5	95
20	5	95
21	6	94
22	6	94
23	6	94
24	7	93
25	7	93
26	7	93
27	8	92
28	8	92
29	9	91
30	9	91

	Avg high (°C)	Avg low (°C)
1	33	26
2	33	26
3	33	26
4	33	26
5	33	26
6	33	26
7	33	26
8	33	26
9	33	26
10	33	26
11	33	26
12	33	26
13	33	26
14	33	26
15	33	26
16	33	26
17	33	26
18	33	26
19	33	26
20	33	26
21	33	26
22	33	26
23	33	26
24	33	26
25	33	26
26	33	26
27	33	26
28	33	26
29	33	26
30	33	26

	Clearer (%)	Cloudier (%)
1	5	95
2	5	95
3	6	94
4	6	94
5	6	94
6	6	94
7	7	93
8	7	93
9	8	92
10	9	91
11	9	91
12	9	91
13	11	89
14	11	89
15	12	88
16	12	88
17	14	86
18	14	86
19	16	84
20	16	84
21	17	83
22	18	82
23	19	81
24	19	81
25	21	79
26	21	79
27	22	78
28	23	77
29	25	75
30	25	75

	Rain chance (%)
1	87
2	87
3	87
4	87
5	88
6	88
7	88
8	88
9	88
10	87
11	87
12	87
13	87
14	87
15	86
16	86
17	86
18	86
19	86
20	85
21	85
22	85
23	85
24	85
25	85
26	85
27	85
28	84
29	84
30	83

	Oppressive (%)	Miserable (%)
1	11	89
2	11	89
3	10	90
4	9	91
5	9	91
6	8	92
7	7	93
8	7	93
9	6	94
10	6	94
11	6	94
12	5	95
13	5	95
14	5	95
15	5	95
16	5	95
17	5	95
18	5	95
19	5	95
20	5	95
21	6	94
22	6	94
23	6	94
24	7	93
25	7	93
26	7	93
27	8	92
28	8	92
29	9	91
30	9	91