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Bield:Fish
Sea surface temperature guide

Gulf of Maine & Stellwagen Bank SST guide.

Northeast1030 mi offshoreCold-water shelf

Stellwagen Bank and the Gulf of Maine offer the northernmost commercial-scale tuna fishery on the East Coast — bluefin tuna that follow herring, mackerel, and sand eel migrations into cold-water shelf waters May through October.

Nearest ports
Gloucester MABoston MAPortsmouth NHPortland ME

Typical SST by month

Climatological norms

Climatologically typical sea surface temperature ranges based on NOAA CoastWatch SST climatologies. Year-to-year variation is real — verify with current SST imagery before each trip.

MonthTypical SSTDominant currentNotes
January3844°FContinental shelf cold waterMid-winter low; offshore generally inaccessible.
February3844°FContinental shelf cold waterSame.
March4046°FContinental shelf cold waterSpring warming begins late month.
April4250°FContinental shelf cold waterCold-water tuna and bluefin migration begins offshore.
Maynow4656°FContinental shelf cold waterBluefin building; bait migrations underway.
June5464°FContinental shelf cold waterSummer pelagic season opens — bluefin, sharks.
July5866°FContinental shelf cold waterPeak Gulf of Maine pelagic month.
August6068°FContinental shelf cold waterSame — bluefin school feeding actively.
September5866°FContinental shelf cold waterLate summer continuing.
October5260°FContinental shelf cold waterFall departures of pelagics.
November4654°FContinental shelf cold waterMost pelagics gone south.
December4048°FContinental shelf cold waterWinter pattern returning.

Species accessibility by month

For each target species, the cells show whether typical monthly SST in Gulf of Maine & Stellwagen Bank falls in that species' preferred or optimal range. Best all-around months: June, July, August, September.

SpeciesJanFebMarAprMayJunJulAugSepOctNovDec
Atlantic Bluefin Tuna
PeakGoodFairPossibleAbsent

Species in range — May

For each species in their preferred SST range this month, the gauge shows the threshold band — verify against current SST imagery before deciding on the run.

  • Atlantic Bluefin TunaOptimal 5972°F
    50°55°60°65°70°75°80°85°90°
    Typical May SST in this zone: 4656°F

Canyon & structure features

  • Stellwagen Bank
  • Jeffreys Ledge
  • Tillies Bank

NOAA marine forecast

NOAA Zone ANZ150

Wind, swell, and tide-stage forecasts for the offshore zone. Pair with SST imagery for trip planning.

Live SST imagery for Gulf of Maine & Stellwagen Bank.

Bield: Fish overlays NOAA CoastWatch SST imagery onto your navigation view, highlights temperature breaks within your target species' threshold band, and alerts you when your home zone hits the optimal window.

This page shows climatological SST patterns for planning purposes. Live SST imagery is available in the Bield: Fish app via NOAA CoastWatch — actual conditions vary year to year and verify before each trip.