Monday, May 4, 2026, started on a cool note in Portland, with temperatures near 57°F at Portland International Airport and clear blue overhead. That chill will not last long. Sunshine and dry air will help the city heat up quickly, sending afternoon highs into the upper 70s and close to 80°F across the Willamette Valley. Out at the coast, cooler heads will prevail, with low clouds and patchy mist expected to creep back in overnight and put a lid on beachside temperatures.
Afternoon Outlook
Meteorologists at the National Weather Service Portland are calling for inland valley highs in the upper 70s to near 80°F today, with similar readings hanging on through midweek. Overnight lows should dip into the low and mid 50s, which will make early mornings feel brisk compared to the warm afternoons. Light southwest breezes around 5 to 10 mph will be the norm in most neighborhoods, more of a gentle nudge than a gust.
Marine Layer And Coastal Fog
A southerly marine surge is keeping a blanket of low stratus and spotty drizzle hugging the Oregon coast and slipping into coastal gaps overnight, which can knock down visibility for beachgoers and early morning ferries. Nearshore winds could briefly gust into the low 20s in miles per hour, while seas are expected to settle from about 6 to 8 feet down to roughly 4 to 5 feet by midweek. Any low clouds that sneak inland should mix out by late morning, setting up sunny, comfortable afternoons for patios, playgrounds and park benches.
What This Means For Your Day
If you are commuting, count on clear and bright afternoon travel, but have a light layer handy for those cooler starts, especially if you are headed toward the river or through coastal gaps before sunrise. Sunscreen will be your friend in the warmer afternoons, even if the air still feels springy. Anyone eyeing an evening escape to the coast should keep one eye on the marine fog potential. For a deeper dive on how this warm spell set up and last weekend's push toward 90°F, check out our earlier Hoodline preview Portland Turns Up The Heat.
Late-Week Rain Chances
Looking ahead, long-range guidance hints that the ridge will weaken a bit by Friday into Saturday (May 8 to 9, 2026). That opens the door for some light rain, mainly from Friday into Saturday, although both timing and coverage are still fuzzy. Current projections keep totals on the modest side, generally at a few tenths of an inch or less for most spots. Check forecasts frequently as the end-of-week details get fine-tuned.
