Väder i Jacó i september
Jacó i september: tryckande hett, genomblött, med ren luft — en chansning, med 30 regndagar.
Uppdaterad september 2026 · klimatnormaler från ERA5-reanalysen
Plats 11 av 12 månader i Jacó · plats 1199 av 1413 resmål att besöka i september · komfort 56/100 (nivå D)
- Dagar
- 28°C
- Nätter
- 24°C
- Regndagar
- 30
- Sol
- 7.6 h
- Luftfuktighet
- 89%
- Dagsljus
- 12 h

Resenärernas anteckningar om Jacó i september
Anteckningar från Monteverde i närheten (81 km bort)
Jacó har inga egna anteckningar för september än — de här handlar om Monteverde, nära nog att dela säsong.
Monteverde-forum threads on September describe this as genuinely deep in the region's off-season, a real tradeoff of fewer crowds against a much higher chance of unsettled conditions on a given day. Posters are consistent showers here often fall overnight rather than through the day, so a visitor can still get a clear, workable stretch for the canopy walks and reserve trails even during a heavier week overall. One short-stay visitor called themselves lucky with a genuinely beautiful couple of days despite planning around the reputation. Regulars describe the elevation as keeping things noticeably cool whenever the cloud cover thins, real layers worth having regardless of how warm San Jose or the coast felt on the same trip. Unpaved roads into town are called noticeably trickier this time of year, a higher-clearance vehicle a real asset. The record: 23.5C days feeling like 25C, 17.9C nights, an extraordinarily high 391mm across nearly 29 days and 90 percent humidity.
Andra månader i Jacó
Regulars are specific this area reads as genuinely drier than areas further south along the same coast, where the rainy season doesn't properly end until mid-to-late December, though conditions here have shifted from the old reputation of reliably rain-free North winds - even the tail end of the month can now bring real rain some years. Our row backs that hot, genuinely wet read, 27.6C reading as a scorching 33C, over 24C nights feeling 29C, with a substantial 278.6mm of rain across 28.5 days and humidity at 86 percent. Regulars are consistent Costa Rica's weather is genuinely location-dependent given how many separate weather systems affect the country, no single verdict applying evenly countrywide. The sea sits at a bath-warm 29.1C. The record: 9.9 hours of sun, a 9.7 kph wind and AQI 32.
The consensus on April for this coast is that it is transitional - not the driest, nowhere near the wettest - and our row proves it exactly: 242.9mm here against 581.8mm in May and 829.3mm in October. What the numbers cannot show is the timing, and the board supplies it: rain on the central Pacific coast comes in the afternoon or overnight, it is warm rain, and the weather apps that promise rain all day every day are wrong about the shape while right about the odds. Our 27.6 rainy days is that same statement. Pack fast-drying clothes rather than cotton, and something light to keep it off. Heat holds at 29.1C reading as 36C, with a 30.3C sea. The record: humidity 83 percent, 10.4 hours of sun and AQI 36.
January opens the hottest, driest run of the Costa Rican year, with strong sun and lower humidity - and regulars still say to expect some rain most days, generally in the afternoon or at night. Our 22.2 precipitation days across 120.4mm is that, five millimetres a day, and one visitor's accounting is the clearest version: roughly eight hours of rain across a week, five of them after dark. Their weather apps had predicted rain daily. The date worth knowing is the 6th: the first days of January are peak holiday travel, and waiting until after about then means the Christmas crowds have gone and prices ease, though it stays high season. A light poncho and a small umbrella cover it. The record: 28.4C over 24.4C reading as 34C, a 28.9C sea and AQI 33.
March is inside the driest and hottest stretch of the Costa Rican year, and our row's 19.7 precipitation days would say otherwise until you read the phrase regulars use: intermittent thunderstorms that do not produce much rain. That is 87.4mm spread across those days, under five millimetres each. Being socked in for days would be strange now; rain is always possible and rarely severe. What the dry season does bring is heat on the coast - 29.6C over a 25.4C night reads as 36C and 30C at 77 percent humidity, and with the Pacific at 29.9C there is nothing cool to get into. Their own figures, high 80s by day and mid 70s at night, match ours closely. The record: 11 hours of sun, a 12.4 kph wind and AQI 38.
Lägg till din egen anteckning från Jacós kort på kartan.
Klimatnormaler för Jacó — september
Månadsmedelvärden från ERA5-reanalysen. AQI är månadens medelvärde för det amerikanska luftkvalitetsindexet.
Trängsel i Jacó i september
Hur mycket folk det är på själva platsen — skollov och storhelger, månaderna en redaktör har märkt upp, och hur eftertraktade vädret gör dem. Aldrig en del av komfortpoängen.
Lugntskollov i 2 av marknaderna som fyller platsen, en av dess sämsta vädermånader(uppskattat)
Mest folkMycket folkMellansäsongLugnt
Bästa månaderna för vädret i Jacó
Rankat efter resmålets egen klimatkomfortpoäng över året — något helt annat än hur trångt det blir (se Trängsel ovan).
Tuffast väderVädret i Jacó toppar januari–mars, bäst kring februari.
Bäst väderHyfsat väderTuffast väder
På gång i Jacó i september
Återkommande säsongsevenemang, naturskådespel, stängningar och helger — utvalda och källhänvisade.
- Säsong
South swell season
1 apr – 31 okt · vanligtvisSurfsäsongThe southern-hemisphere swells arrive through the middle of the year. Playa Hermosa a few minutes down the coast is the serious wave and holds national contests; Jaco's own beach is where people learn.
- Säsong
Green season
1 maj – 30 nov · vanligtvisMonsunMornings stay clear and the rain comes after lunch, hard and short. Rates drop by a third, the hills opposite turn over, and September and October are the two months that genuinely stay grey.
- Natur
Humpback whales
15 jul – 15 nov · vanligtvisValsäsongSouthern-hemisphere humpbacks calve along this coast from July into November, which with the northern group arriving December to March gives Costa Rica one of the longest whale seasons anywhere.
- Natur
Olive ridley nesting
15 aug – 15 dec · vanligtvisSköldpaddornas äggläggningOlive ridleys nest on Playa Hermosa from August, heaviest through September and October, and the hatchery releases at dusk. The beach is patrolled at night and you go with the project or not at all.
- Säsong
Wet season
MonsunRisk30 rainy days and about 720 mm in the month — the real kind of rainy season, not afternoon showers.
från klimatnormalerna
I närheten, och något är på gång
Inom 300 km från Jacó — en dagstur eller ett kort hopp — med något på gång den här månaden. Aldrig en del av komfortpoängen.
Var ligger Jacó?
Jacó i september — vanliga frågor
- Är september en bra tid att besöka Jacó?
- Jacó i september: tryckande hett, genomblött, med ren luft — en chansning, med 30 regndagar. Månaden ligger på plats 11 av 12 för Jacó enligt SeasonMaps komfortpoäng (56/100).
- Hur är vädret i Jacó i september?
- I september har Jacó i snitt 27.7 °C som dagshögsta och 24.3 °C som nattlägsta, med ungefär 719.5 mm regn fördelat på cirka 30 regndagar.
- Hur är luftkvaliteten i Jacó i september?
- Jacó har ett genomsnittligt amerikanskt luftkvalitetsindex (AQI) på ungefär 26 i september.
Inom 300 km: Nosaras Arribada at Ostional, runt 1 jul – 31 dec och Tortugueros Green turtle nesting, 1 jul – 31 okt.