Været i St. Louis i september
september i St. Louis: hett, regnfullt, med ren luft — en av de beste månedene å reise hit.
Oppdatert september 2026 · klimanormaler fra ERA5-reanalysen
Nr. 2 av 12 måneder i St. Louis · Nr. 511 av 1413 reisemål å besøke i september · komfort 85/100 (nivå A)
- Dager
- 29°C
- Netter
- 15°C
- Våte dager
- 5
- Sol
- 10.2 h
- Luftfuktighet
- 67%
- Dagslys
- 12 h

Reisendes notater om St. Louis i september
September is the month St Louis regulars pick alongside May, and their framing is that it improves as it runs: the first week or so can still be properly hot, a hangover from a humid July and August, and the comfort builds week by week, with the last third the part they recommend. Mid-September sits in the low 80s Fahrenheit, though they are careful to add that the odd hot day still jumps up out of nowhere. It is fairly dry by local standards too - our row's 83.1mm falls across only 5.3 days, which is thunderstorm rain rather than drizzle - and that combination is why the outdoor events calendar fills up. The record: 28.9C days that feel like 30C, 14.7C nights, humidity 67 percent and 10.2 hours of sun.
Andre måneder i St. Louis
Regulars describe this month as a genuine toss-up rather than a settled pattern - balmy and pleasant one visit, oppressively humid like the Deep South the next, with the odds of the muggier version rising the closer the calendar gets to July. Our row backs the real heat and building humidity, 31.3C reading as a hot 34C at 66 percent humidity, over 18C nights, with 91.3mm of rain across 6.9 days. Regulars comparing this month to August don't find a clear winner on crowds either, both drawing similar numbers, so the honest deciding factor ends up being which version of the heat gamble a visitor is more willing to take. The record: 12 hours of sun, a 14.7 kph wind and AQI 68.
Regulars call April the most beautiful month here for the blossom and new leaves, and immediately qualify it: this is also when storms and rapid weather swings are most likely, chilly evenings alongside daytime warmth, and their standing advice is to check a local forecast a day or two out rather than trust a seasonal average. Our row shows the range that produces - 19.9C over 6.5C, with 109.5mm of rain across 9.1 days and a trace of snow, 0.5cm, still possible early in the month. Spring and autumn are named as this city's best seasons overall, and April earns that with qualifications rather than without them. The record: humidity 64 percent, 9 hours of sun, a 20.6 kph wind and AQI 42.
Locals put October among the best weeks here and give a date for the end of it: the turn usually does not happen until around Halloween, so the month is autumn in colour and late summer in temperature. Our row reads 21.7C by day against 7.7C at night, a fourteen-degree fall that catches people who packed for the afternoon, and the felt figures are 20C and 6C in a 17.2 kph wind. Rain is light and infrequent, 70.8mm across 5.6 days, and the 0.1cm in the snow column is the first hint of the season rather than a forecast. Early October also beats the fall road-trip crowds further out. The record: humidity 66 percent, 7.8 hours of sun and AQI 36.
Ask the Saint Louis forum for the best time of year and the answer keeps coming back the same: May, then later September into early October, from both a weather and an outdoor-events point of view. The reasoning is what follows it - June through early September is described as quite hot and humid, not New Orleans hot but close, and worth avoiding where you have the choice. May gets the festival calendar without the swelter. The trade-off is water: it is one of the wettest months on the calendar here, though it arrives in bursts rather than all-day grey. The record: 25.6C days, 13.2C nights, 9.8 precipitation days carrying 139.1mm between them, humidity near 70 percent, 10 hours of sun and AQI 53.
Notatene som gjelder hele året, ligger på oversikten over St. Louis. Legg til ditt eget notat fra kortet til St. Louis på kartet.
Klimanormaler for St. Louis — september
Månedsgjennomsnitt fra ERA5-reanalysen. AQI er den gjennomsnittlige amerikanske luftkvalitetsindeksen for måneden.
Trengsel i St. Louis i september
Hvor travelt selve stedet er — skoleferier og fellesferier, månedene en redaktør har merket, og hvor ettertraktet været gjør dem. Aldri en del av komfortscoren.
ToppsesongJapanese Festival, Great Forest Park Balloon Race, Summer break i United States(anslag)
ToppsesongTraveltSkuldersesongRolig
Beste måneder for været i St. Louis
Rangert etter reisemålets egen klimakomfortscore gjennom året — noe annet enn hvor travelt det blir (se Trengsel over).
Best værDet beste været i St. Louis kommer i mai, september og oktober — atskilte vinduer, ikke én sammenhengende sesong.
september omfatter Japanese Festival.
Best værBrukbart værTøffest vær
Hva som skjer i St. Louis i september
Faste sesonghendelser, naturfenomener, stengninger og helligdager — kuratert og kildebelagt.
- Regel
Arch tram timed tickets
1. jan – 31. desBestill tidligThe ride to the top of the Arch is sold as a timed slot and the summer and holiday-weekend trams go days ahead. The museum underneath is free and needs no ticket at all. Kilde ↗
- Fare
Summer heat and humidity
15. jun – 5. sep · vanligvisEkstrem varmeThe river valley traps humidity and the heat index runs well above the thermometer for weeks. Forest Park is a morning walk in July, and the Arch grounds have no shade at all. Kilde ↗
- Festival
Japanese Festival
30. aug – 8. sep · vanligvisStor festivalMye folkThree days at the Botanical Garden over Labor Day weekend, running since 1977 and one of the largest of its kind in the country. Evening taiko in the Japanese garden is the reason to go. Kilde ↗
- Festival
Great Forest Park Balloon Race
14.–22. sep · vanligvisSportsarrangementMye folkA Friday-night balloon glow and a Saturday race from Forest Park, free, with seventy balloons and a six-figure crowd on the grass. The most-attended single-day balloon event in America. Kilde ↗
Hvor ligger St. Louis?
St. Louis i september — ofte stilte spørsmål
- Er september et godt tidspunkt å besøke St. Louis?
- september i St. Louis: hett, regnfullt, med ren luft — en av de beste månedene å reise hit. Måneden ligger på plass 2 av 12 for St. Louis på SeasonMaps komfortscore (85/100).
- Hvordan er været i St. Louis i september?
- I september har St. Louis i snitt en dagtemperatur på 28.9°C og en natttemperatur på 14.7°C, med rundt 83.1 mm regn fordelt på omtrent 5.3 regndager.
- Hvordan er luftkvaliteten i St. Louis i september?
- St. Louis har en gjennomsnittlig amerikansk luftkvalitetsindeks på rundt 50 i september.