30YearWeather
Portland in September
Portland weather in September - United States
😊Warm & Pleasant

Portland Weather in September

Plan your September trip to Portland, United States. Based on 30 years of NASA data, expect temperatures of 24°C (high) to 12°C (low), with 15% rain probability and 8 hours of daily sunshine. Great conditions with only 5 rainy days expected.

Avg High
24°C

Hottest around day 3

Avg Low
12°C

Coolest around day 30

Rainy Days
5days

15% avg rain chance

Sunshine
8hrs/day

Autumn season

Portland September Weather Calendar

Click any day to see detailed weather information

Currency

USD

$ United States dollar

Language

English

Driving

Right side

Safety

Moderate Safety

GPI: 2.44

Travel Intelligence

Exclusive flight analytics & health data for Portland

Smart Flight Estimator

Airport-to-Airport Logistics

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Flight Connectivity Analysis

Airport traffic data & seasonal patterns

Well Connected
62/ 100
Traffic Index

Popular destination

Peak Daily Arrivals

0

slots per day

Peak

Aug

Low

Jan

Monthly Traffic Distribution

203
Jan
204
Feb
225
Mar
256
Apr
287
May
297
Jun
324
Jul
326
Aug
305
Sep
275
Oct
209
Nov
253
Dec
Traffic Level
Low Season

Key Connections

Seattle Tacoma (SEA)
Los Angeles (LAX)
Denver (DEN)
Phoenix Sky Harbor (PHX)
San Francisco (SFO)

Health & Safety Advisory

CDC travel health recommendations

No Requirements

No Special Vaccinations Required

Standard travel precautions apply

Source: CDC Travelers' Health

View Complete Health Guide

Is September a Good Time to Visit Portland?

👍Very good conditions overall
Short Answer

Popular September in Portland offers 24°C and 15% rain chance - excellent conditions that attract maximum visitors. Book 3-6 months ahead for best rates.

Decision Factors

Peak tourist season

94% of annual peak - expect crowds and peak prices

Ideal temperature range

24.1°C - perfect for sightseeing and outdoor activities

Near active volcano: Mount St. Helens

Medium volcanic risk

Plenty of sunshine

9.8h of sunshine daily

Good For

  • 👨‍👩‍👧‍👦
    Families with children

    Comfortable 24.1°C temperatures and low 15% rain risk

  • 👴
    Elderly travelers

    Comfortable 24.1°C temperature range with manageable humidity

  • 🥾
    Outdoor enthusiasts

    Ideal hiking conditions: 24.1°C, 15% rain chance

  • 📸
    Photographers

    9.8h sunshine, 56% clear skies for golden hour shots

  • 🏛️
    Cultural tourists

    Comfortable conditions for exploring museums and sites

Who Should Avoid

  • 💰
    Budget travelers

    Peak season means premium prices everywhere

900 observations30-year historical data
Confidence: 95%

"According to 30YearWeather's analysis of 30 years of NASA POWER satellite data,Portland in September averages 24°C with 15% precipitation probability."

📊 Source: 30YearWeather.com🛰️ Data: NASA POWER (1991-2021)View Methodology →

Frequently Asked Questions: Portland in September

What are the temperatures in Portland in September?

Daytime highs average 24°C, nights drop to 12°C. Temperatures remain fairly consistent.

How many rainy days in Portland in September?

Expect around 5 days with measurable rainfall. Rain is unlikely to disrupt plans.

What to wear in Portland in September?

Comfortable casual wear with a light jacket for evenings.

Is September peak season in Portland?

This is typically peak season with higher prices. Book 2-3 months ahead.