Vejret i San Diego i september
San Diego i september: varmt, tørt, med lummer luft — et fremragende tidspunkt at tage afsted.
Opdateret september 2026 · klimanormaler fra ERA5-reanalysen
Nr. 3 af 12 måneder i San Diego · Nr. 195 af 1413 rejsemål at besøge i september · komfort 91/100 (niveau S)
- Dage
- 26°C
- Nætter
- 19°C
- Våde dage
- 1
- Sol
- 11.1 h
- Luftfugtighed
- 77%
- Dagslys
- 12 h

Noter fra rejsende om San Diego i september
Regulars call September the best month here and give two reasons that have nothing to do with the air. The ocean is at its warmest of the year - they put it in the low seventies Fahrenheit and our column reads 20.3C - and the crowds go home after Labour Day while the weather carries on unchanged. Our row gives 25.8C reading as 27C over 19.4C nights, with 5.5mm of rain in the whole month and 11.1 hours of sun. The marine layer that shapes June has gone by now. Humidity is high at 77 percent but the sea breeze at 14.9 kph handles it. The record: a dew point of 16.7C and AQI 53.
Andre måneder i San Diego
Regulars explain the region's forecast confusion with a specific structure: four distinct zones each day - coast (coolest), inland (at least 10 degrees warmer), mountains (more rain, occasional snow) and desert - so a single citywide number always hides real variation. Our row backs the pleasant coastal read this month, 24.6C over 16.3C nights, with rain minimal at 6.1mm across under a day. Regulars call this one of the best months overall, generally clear, dry, sunny and warm, with the occasional Santa Ana condition pushing dry desert winds and temperatures into the 80s Fahrenheit even on the coast. The sea is cooling toward 19.2C, on the cold side for a swim by regulars' own standards. The record: humidity 75 percent, 10.2 hours of sun, a 14.3 kph wind and AQI 63.
May Gray and June Gloom are the local names for a marine layer that can sit over the city all day in late spring, and regulars say it weakens through June and is usually gone by July. What replaces it is a daily cycle rather than a season: cloud overnight, burning off through the morning and clear by about noon, with the cloud rolling back in off the ocean in the evening. Some years the layer does hang on into July, which they call unusual. Our row is as maritime as that sounds - 24.7C days and 19.4C nights, five degrees apart - with 1mm of rain, 13 hours of sun and a 20C sea. The record: humidity 78 percent, a 14.6 kph wind and AQI 51.
San Diego forum regulars keep December's range wide but genuinely mild: “highs will be somewhere between 50 and 80 and the lows between 35 and 55,” with a more typical read “temps in the 60s°F during the day” and chilly mornings and evenings. Rain totals for the whole month run modest — “about 1.3 inches” — but nobody can tell more than a week or 10 days out whether a given trip lands wet or dry. Standard packing: jeans with a long-sleeve tee or light jacket by day, a proper coat once the sun drops, and regulars specifically say to leave the umbrella at home since rain is infrequent enough not to be worth the space. Our record: 17.6°C days, 9.8°C nights, 6 rain days and 59.7mm of rain — mild and mostly dry, matching the “generally sunny and cool, occasional wet week” read.
San Diego forum regulars call February the most variable month of the year, not a reliable read either way: “it could rain for a couple of days and be mostly cloudy the rest of that week with highs in the upper 50s, or it could be 80 degrees.” Typical readings run “high 60s or low 70s” by day, “50s or possibly even 40s” at night, with the coast in particular cooling fast once the sun drops. Statistically the rainiest month, but likely to be mostly dry in practice since San Diego gets so little rain overall — the wet season (November through March) peaks around now without ever amounting to much. The sea stays too cold to swim regardless of how warm the air gets. Our record: 17.2°C days, 8.5°C nights, 7.2 rain days and a 13.8°C sea — mild with real day-to-day variability, and a sea that backs the “too cold to swim” read.
Noterne for hele året findes på oversigten over San Diego. Tilføj din egen note fra San Diego på kortet.
Klimanormaler for San Diego — september
Månedsgennemsnit fra ERA5-reanalysen. AQI er det gennemsnitlige amerikanske luftkvalitetsindeks for måneden.
Travlhed i San Diego i september
Hvor travlt der er på selve stedet — skoleferier og masseferier, de måneder en redaktør har markeret, og hvor eftertragtet vejret gør dem. Aldrig en del af komfortscoren.
TætpakketDel Mar summer racing, Summer break i United States(anslået)
TætpakketTravltSkuldersæsonStille
Bedste måneder for vejret i San Diego
Rangeret efter dette rejsemåls egen klimakomfortscore året igennem — noget andet end, hvor travlt der bliver (se Travlhed ovenfor).
Bedste vejrVejret i San Diego topper juli–september, bedst omkring august.
september rummer Del Mar summer racing.
Bedste vejrPænt vejrHårdeste vejr
Det sker i San Diego i september
Tilbagevendende sæsonbegivenheder, naturfænomener, lukninger og helligdage — kurateret og med kilder.
- Festival
Del Mar summer racing
17. jul. – 7. sep. · normaltSportsbegivenhedTætpakketThoroughbred racing by the sea from mid-July to Labor Day, opening day being as much a hat competition as a race meeting. Concerts follow the last race on Fridays. Kilde ↗
- Sæson
Sea at its warmest
1. aug. – 30. sep. · normaltHavet er varmt nokThe Pacific here takes all summer to warm up and only gets comfortable without a wetsuit in August and September, which is also when the marine layer has finally gone.
- Risiko
Santa Ana wind and fire season
15. sep. – 15. dec. · normaltRøgsæsonOffshore winds off the desert bring the hottest days of the San Diego year in autumn and the county's worst fire risk with them. The coast gets the heat; the backcountry gets the fires. Kilde ↗
Lige i nærheden sker der noget
Inden for 300 km fra San Diego — en dagstur eller et kort hop — hvor der sker noget denne måned. Aldrig en del af komfortscoren.
Hvor ligger San Diego?
San Diego i september — ofte stillede spørgsmål
- Er september et godt tidspunkt at besøge San Diego?
- San Diego i september: varmt, tørt, med lummer luft — et fremragende tidspunkt at tage afsted. Måneden ligger nr. 3 ud af 12 for San Diego på SeasonMaps komfortscore (91/100).
- Hvordan er vejret i San Diego i september?
- I september har San Diego i gennemsnit en dagtemperatur på 25.8 °C og en nattemperatur på 19.4 °C, med omkring 5.5 mm regn fordelt på cirka 0.8 regnvejrsdage.
- Hvordan er luftkvaliteten i San Diego i september?
- San Diego har et gennemsnitligt amerikansk luftkvalitetsindeks på omkring 53 i september.
Inden for 300 km: Laguna Beach's Sawdust Art Festival, omkring 24. jun. – 6. sep. og Los Angeles' Sea at its warmest, 1. aug. – 30. sep..