White Marlin sea surface temperature guide.
White marlin are the iconic East Coast billfish — Mid-Atlantic canyon waters in August produce the most concentrated white marlin fishery in the world. Stock is overfished and under ICCAT rebuilding; release is the standard.
SST threshold gauge
The water temperature ranges that determine where white marlin hold and feed. Hard thresholds (dashed lines) are values outside which fish actively depart or become inactive.
Depth profile & SST reliability
White marlin feed in the upper water column and are well-predicted by surface SST.
Current systems & structure
White marlin concentrate in warm core eddies and along the Gulf Stream's western wall. Mid-Atlantic canyon edges in summer host the bulk of the East Coast fishery.
Best zones for white marlin — May
Zones where typical May SST falls in white marlin's preferred range.
Zone-by-zone calendar
For each zone where white marlin are present, the chart overlays the zone's typical monthly SST range with the species' preferred and optimal ranges. Months where the bands overlap are when fish are in range.
Northeast
| Month | Zone SST | Status |
|---|---|---|
| Jan | 42–48°F | Outside |
| Feb | 42–48°F | Outside |
| Mar | 44–50°F | Outside |
| Apr | 46–54°F | Outside |
| Maynow | 52–60°F | Outside |
| Jun | 60–68°F | Outside |
| Jul | 65–75°F | Peak |
| Aug | 68–78°F | Peak |
| Sep | 64–72°F | Fishable |
| Oct | 56–64°F | Outside |
| Nov | 50–58°F | Outside |
| Dec | 44–52°F | Outside |
Mid-Atlantic
| Month | Zone SST | Status |
|---|---|---|
| Jan | 44–52°F | Outside |
| Feb | 44–50°F | Outside |
| Mar | 44–52°F | Outside |
| Apr | 46–56°F | Outside |
| Maynow | 54–64°F | Outside |
| Jun | 62–72°F | Fishable |
| Jul | 68–78°F | Peak |
| Aug | 70–80°F | Peak |
| Sep | 66–74°F | Fishable |
| Oct | 58–66°F | Outside |
| Nov | 52–60°F | Outside |
| Dec | 46–54°F | Outside |
| Month | Zone SST | Status |
|---|---|---|
| Jan | 46–54°F | Outside |
| Feb | 46–54°F | Outside |
| Mar | 48–56°F | Outside |
| Apr | 50–60°F | Outside |
| Maynow | 56–66°F | Outside |
| Jun | 64–74°F | Fishable |
| Jul | 70–80°F | Peak |
| Aug | 72–82°F | Peak |
| Sep | 68–76°F | Peak |
| Oct | 60–68°F | Outside |
| Nov | 54–62°F | Outside |
| Dec | 48–56°F | Outside |
| Month | Zone SST | Status |
|---|---|---|
| Jan | 48–58°F | Outside |
| Feb | 48–56°F | Outside |
| Mar | 50–60°F | Outside |
| Apr | 54–64°F | Outside |
| Maynow | 60–70°F | Outside |
| Jun | 68–78°F | Peak |
| Jul | 72–82°F | Peak |
| Aug | 74–84°F | Peak |
| Sep | 70–80°F | Peak |
| Oct | 64–72°F | Fishable |
| Nov | 56–64°F | Outside |
| Dec | 50–60°F | Outside |
| Month | Zone SST | Status |
|---|---|---|
| Jan | 58–66°F | Outside |
| Feb | 56–64°F | Outside |
| Mar | 58–66°F | Outside |
| Apr | 64–72°F | Fishable |
| Maynow | 68–76°F | Peak |
| Jun | 74–82°F | Peak |
| Jul | 78–84°F | Fishable |
| Aug | 78–84°F | Fishable |
| Sep | 76–82°F | Peak |
| Oct | 70–78°F | Peak |
| Nov | 64–72°F | Fishable |
| Dec | 60–68°F | Outside |
South Atlantic
| Month | Zone SST | Status |
|---|---|---|
| Jan | 58–66°F | Outside |
| Feb | 56–64°F | Outside |
| Mar | 60–68°F | Outside |
| Apr | 66–74°F | Fishable |
| Maynow | 70–78°F | Peak |
| Jun | 74–82°F | Peak |
| Jul | 78–84°F | Fishable |
| Aug | 78–84°F | Fishable |
| Sep | 76–82°F | Peak |
| Oct | 70–78°F | Peak |
| Nov | 64–72°F | Fishable |
| Dec | 60–68°F | Outside |
Gulf of Mexico
| Month | Zone SST | Status |
|---|---|---|
| Jan | 64–72°F | Fishable |
| Feb | 64–70°F | Outside |
| Mar | 68–74°F | Fishable |
| Apr | 72–78°F | Peak |
| Maynow | 76–82°F | Peak |
| Jun | 80–84°F | Fishable |
| Jul | 82–86°F | Outside |
| Aug | 82–86°F | Outside |
| Sep | 80–84°F | Fishable |
| Oct | 76–82°F | Peak |
| Nov | 70–78°F | Peak |
| Dec | 66–74°F | Fishable |
Conservation & regulations
Overfished — under ICCAT recovery plan. Catch and release strongly recommended; tag required to retain. HMS permit needed for recreational billfish targeting. Verify current rule before harvest.
Stock assessment source →White marlin fishing is sight fishing at the surface — pitch baits to fish coming up on a teaser. Find them on the warm side of a 2–3°F break in 73–79°F water. Mid-Atlantic canyon mornings in August are the iconic bite.
Sources
SST threshold data is summarized from agency and research sources. Year-to-year ocean conditions vary; verify current SST imagery before each trip.
See live SST for your offshore zone.
Bield: Fish overlays NOAA CoastWatch SST imagery on your chartplotter view, highlights the temperature breaks that match white marlin thresholds, and alerts you when your home zone hits the 73–79°F window.