Vejret i Washington (DC) i september

Washington i september: hedt, regnfuldt, med ren luft — et fremragende tidspunkt at tage afsted.

Opdateret september 2026 · klimanormaler fra ERA5-reanalysen

Washington🇺🇸 United States · Nordøst & det atlantiske Canada · By80
  1. 59jan.
  2. 63feb.
  3. 73mar.
  4. 83apr.
  5. 87maj
  6. 78jun.
  7. 65jul.
  8. 70aug.
  9. 80sep.
  10. 85okt.
  11. 71nov.
  12. 58dec.

Nr. 4 af 12 måneder i Washington · Nr. 708 af 1413 rejsemål at besøge i september · komfort 80/100 (niveau A)

Dage
28°C
Nætter
17°C
Våde dage
8
Sol
8.6 h
Luftfugtighed
74%
Dagslys
12 h
Washington, United States
Foto: Mark Stebnicki · Pexels

Noter fra rejsende om Washington i september

Regulars time this city by the school calendar. Labour Day is the first Monday of September and ends the summer season; October brings the school groups back in force; the fortnight between is the quietest good weather of the year. The weather follows the same split - the first week is still summer, mid-80s with the humidity to match, and the drier air does not usually arrive until mid-to-late month. Our row averages 27.8C reading as 30C at 74 percent humidity with a 16.1C dew point, over 17.3C nights, and 108.4mm of rain across 8.1 days. Book the second half if you can. The record: 8.6 hours of sun and AQI 47.
AfterLabourDayBeforeTheSchoolTrips · september · for 3 dage siden · Læs mere på Tripadvisor ↗

Andre måneder i Washington

June here is hot and humid but not yet August, and regulars are precise about the pattern: mid to high eighties by day, sixties at night, and afternoon thunderstorms that come out of nowhere, rain hard for a few minutes and leave the air more humid than before. Our row gives 29.7C reading as 32C over 18.6C nights, with 107.1mm across 9.4 days, which is eleven millimetres a time. Their packing advice follows the humidity - loose natural fibres in light colours, because synthetics turn into plastic bags - and their warning is the opposite problem, that indoor air conditioning is usually set far too cold. The record: humidity 69 percent, 11.4 hours of sun and AQI 68.
NaturalFibresAndAShortStorm · juni · for 3 dage siden · Læs mere på Tripadvisor ↗
Washington DC-forum threads on late May draw a before/after line at Memorial Day: earlier in the month runs fair and warm with just the odd afternoon thunderstorm, while posters note humidity climbs noticeably by late May and into June, ahead of July and August's muggier stretch. The record backs the thunderstorm read more than the 'dry spring' reputation: 137mm of rain across more than twelve days, the wettest month on this destination's calendar, alongside 24.6C days, 13.4C nights and 9.3 hours of sun. Good jacket-optional weather, but pack for rain more than forum nostalgia about 'before the humidity' suggests.
TidalBasinLateMay · maj · for 4 dage siden · Læs mere på Tripadvisor ↗
Washington DC forum threads describe January as genuinely the coldest month, with average highs in the low 40s Fahrenheit and lows in the mid-20s, plus real wind chill that makes it feel colder still. A typical winter brings around 6 inches of snow total for the month in smaller spurts rather than one big dump, though posters noted an occasional major coastal storm can bring far more at once - DC still gets meaningfully less snow than cities like Boston given its more southern, coastal-influenced position. The consistent packing advice: several thinner warm layers under a proper coat work better than one very thick jacket, plus wool accessories that handle wet weather better than cotton.
NationalMallRegular · januar · for 5 dage siden · Læs mere på Tripadvisor ↗
Locals give October a spread rather than a temperature: "temps can be 30–90. Usually 40–70" °F, with "daytime highs in the low 60s around then." That thirty-degree usual range across a single month is the thing to plan for — the first week and the last week can feel like different seasons. Their advice on forecasts is to look four or five days out and no further, because it varies widely. The month's reputation is good enough that one regular describes it as when people from colder places start heading south. Our record puts October at 20.8°C days and 12.1°C nights with 9 rain days — comfortably inside the forum's "usually 40–70" band, and well clear of the humidity that defines a Washington summer.
Tripadvisor community · oktober · for 6 dage siden · Læs mere på Tripadvisor ↗

Noterne for hele året findes på oversigten over Washington. Tilføj din egen note fra Washington på kortet.

Klimanormaler for Washington — september

Dagtemperatur28°C / 82°F🥵 hedt
Nattemperatur17°C / 63°F
Føles som (dag)30°C / 86°F
Nedbør108 mm / 4.3 in🌧 regnfuldt
Regnvejrsdage8 dage
Luftfugtighed74 %💧 fugtigt
Dugpunkt16°C / 61°F
Solskin8.6 t/dag
Dagslys12.4 t
Vind13 km/t / 8 mph
Luftkvalitet (US AQI)47🍃 god

Månedsgennemsnit fra ERA5-reanalysen. AQI er det gennemsnitlige amerikanske luftkvalitetsindeks for måneden.

Travlhed i Washington 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.

TravltSummer break i United States(anslået)

JFMAMJJASOND

TætpakketTravltSkuldersæsonStille

Bedste måneder for vejret i Washington

Rangeret efter dette rejsemåls egen klimakomfortscore året igennem — noget andet end, hvor travlt der bliver (se Travlhed ovenfor).

Pænt vejrDet bedste vejr i Washington kommer i april, maj og oktober — adskilte vinduer, ikke én sammenhængende sæson.

JFMAMJJASOND

Bedste vejrPænt vejrHårdeste vejr

Det sker i Washington i september

Tilbagevendende sæsonbegivenheder, naturfænomener, lukninger og helligdage — kurateret og med kilder.

  • Regel

    Washington Monument timed tickets

    1. jan. – 31. dec.Book tidligt

    The lift to the top runs on timed tickets released online a month ahead, with a small same-day batch in the morning. The African American History museum works the same way in the busy months. Kilde ↗

  • Risiko

    Summer heat and humidity

    20. jun. – 5. sep. · normaltEkstrem varme

    The city was built on a river flat and the summer behaves accordingly, with afternoon thunderstorms and heat advisories through July and August. The monuments walk is best done at seven in the morning. Kilde ↗

  • Sæson

    August recess

    1. aug. – 5. sep.Lukket uden for sæsonen

    Congress goes home, the lobbying and lawyer city empties with it, and downtown restaurants that live on expense accounts run their quiet weeks. Hotel rates fall while the museums stay open.

Det sker rundt om i verden i september →

Lige i nærheden sker der noget

Inden for 300 km fra Washington — en dagstur eller et kort hop — hvor der sker noget denne måned. Aldrig en del af komfortscoren.

Hvor ligger Washington?

Indlæser kort…

Washington i september — ofte stillede spørgsmål

Er september et godt tidspunkt at besøge Washington?
Washington i september: hedt, regnfuldt, med ren luft — et fremragende tidspunkt at tage afsted. Måneden ligger nr. 4 ud af 12 for Washington på SeasonMaps komfortscore (80/100).
Hvordan er vejret i Washington i september?
I september har Washington i gennemsnit en dagtemperatur på 27.8 °C og en nattemperatur på 17.3 °C, med omkring 108.4 mm regn fordelt på cirka 8.1 regnvejrsdage.
Hvordan er luftkvaliteten i Washington i september?
Washington har et gennemsnitligt amerikansk luftkvalitetsindeks på omkring 47 i september.

Inden for 300 km: Philadelphia's Philadelphia Fringe Festival, omkring 4.–28. sep. og Virginia Beach's Neptune Festival, 25.–27. sep..

Vejret i Washington (DC) i september: 28 °C, 8 regnvejrsdage, 9 t sol | SeasonMap