Today's barometric pressure in Portland, a 48-hour pressure chart, and a risk score for weather-triggered migraine and headache, based on pressure drops, humidity, and temperature changes.
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Portland faces Casco Bay on the Gulf of Maine, where sea surface temperatures and storm tracks combine to produce the widest pressure swings in this dataset at up to 17 hPa. Storm lows near 990 hPa arrive several times each winter.
Worst season for migraines: February, December and January. Storms crossing the Gulf of Maine draw energy from one of the fastest-warming bodies of water on the planet. Nor'easters frequently reach peak intensity right offshore, putting the city under the steepest part of the pressure gradient.
Common triggers in Portland: rapidly intensifying offshore storms, Gulf of Maine moisture and energy supply, prolonged low pressure through multi-day systems. Casco Bay's many islands and inlets create local wind and temperature variation across short distances. More significantly, the city sits at the latitude where winter storms most often undergo rapid intensification, a process meteorologists call bombogenesis, defined by a pressure drop of 24 hPa in 24 hours. Portland experiences these more often than almost any US city.
Typical pressure: Portland averages 1012 hPa at rest, measured at the city's own elevation rather than corrected to sea level, and storm systems can push readings down to 990 hPa. Swings of 7-17 hPa over 24 hours are common during active weather and fall within the range most associated with pressure-triggered migraines.
2026 index: Portland is not one of the 100 metros ranked in our 2026 U.S. Migraine Risk Index, which shows how they compare.
Can Portland weather trigger migraines?
Yes. Portland experiences 7-17 hPa barometric pressure swings, and research shows pressure drops are one of the most common migraine triggers. The city's specific patterns include rapidly intensifying offshore storms, Gulf of Maine moisture and energy supply, prolonged low pressure through multi-day systems.
What time of year are migraines worst in Portland?
In Portland the most barometrically volatile stretch of the year falls in February, December and January. That is when weather is most likely to play a part, if weather is a trigger for you at all. See when migraine weather season starts across the U.S.
Is there a barometric pressure headache forecast for Portland?
This page works as one. Many people call a headache that arrives with a weather change a barometric pressure headache, and this forecast tracks the pressure drops, humidity and temperature swings behind that idea. The score covers the next 24 hours in Portland and the chart shows the next 48. It is built on migraine research, so treat it as a rough guide for other headaches. A sudden, severe headache needs urgent medical care, whatever the weather.
Your own forecast
This page shows the weather risk for everyone in Portland. The MigrAid app learns yours. It saves the barometric pressure, humidity and temperature with every migraine you log, shows whether Portland's swings really line up with your attacks, and alerts you when conditions match your own trigger history.