National Weather Service Forecast for: Portsmouth NH
Issued by: National Weather Service Gray/Portland, ME
Updated: 9:48 am EDT Mar 19, 2026
 
This
Afternoon
This Afternoon: Mostly sunny, with a high near 40. Southeast wind 5 to 10 mph.
Mostly Sunny

 Tonight

Tonight: Partly cloudy, with a low around 28. Southwest wind around 5 mph.
Partly Cloudy

 Friday

Friday: Increasing clouds, with a high near 49. Calm wind becoming south around 5 mph in the afternoon.
Increasing
Clouds

 Friday
Night
Friday Night: Rain likely, mainly after 10pm. Mostly cloudy, with a low around 36. South wind around 5 mph. Chance of precipitation is 70%.
Rain Likely

 Saturday

Saturday: Partly sunny, with a high near 51. West wind 5 to 10 mph.
Partly Sunny

 Saturday
Night
Saturday Night: Mostly cloudy, with a low around 32.
Mostly Cloudy

 Sunday

Sunday: A 40 percent chance of rain. Mostly cloudy, with a high near 48.
Chance Rain

 Sunday
Night
Sunday Night: A chance of rain before 11pm, then a chance of rain and snow. Mostly cloudy, with a low around 28. Chance of precipitation is 50%.
Chance
Rain/Snow

 Monday

Monday: A chance of rain and snow before 11am, then a chance of snow between 11am and 4pm. Mostly cloudy, with a high near 40. Chance of precipitation is 40%.
Chance
Rain/Snow
then Chance
Snow
Hi 40 °F Lo 28 °F Hi 49 °F Lo 36 °F Hi 51 °F Lo 32 °F Hi 48 °F Lo 28 °F Hi 40 °F

 

This Afternoon
 
 Mostly sunny, with a high near 40. Southeast wind 5 to 10 mph.
Tonight
 
 Partly cloudy, with a low around 28. Southwest wind around 5 mph.
Friday
 
 Increasing clouds, with a high near 49. Calm wind becoming south around 5 mph in the afternoon.
Friday Night
 
 Rain likely, mainly after 10pm. Mostly cloudy, with a low around 36. South wind around 5 mph. Chance of precipitation is 70%.
Saturday
 
 Partly sunny, with a high near 51. West wind 5 to 10 mph.
Saturday Night
 
 Mostly cloudy, with a low around 32.
Sunday
 
 A 40 percent chance of rain. Mostly cloudy, with a high near 48.
Sunday Night
 
 A chance of rain before 11pm, then a chance of rain and snow. Mostly cloudy, with a low around 28. Chance of precipitation is 50%.
Monday
 
 A chance of rain and snow before 11am, then a chance of snow between 11am and 4pm. Mostly cloudy, with a high near 40. Chance of precipitation is 40%.
Monday Night
 
 Partly cloudy, with a low around 21.
Tuesday
 
 Mostly sunny, with a high near 40.
Tuesday Night
 
 Partly cloudy, with a low around 24.
Wednesday
 
 Mostly sunny, with a high near 44.

 

Forecast from NOAA-NWS for Portsmouth NH.