SST Analysis — Sea Surface Temperatures

Global sea surface temperature analysis from NOAA OISST satellite data, plotted by PettusPlots. SST is one of the most important variables for tropical cyclone development, ENSO monitoring, and seasonal forecasting. Water temperatures above 26.5C are generally required for tropical cyclogenesis.

SST Maps

Product: Region:

Key SST Time Series

Nino 3.4 SST Anomaly CPC / PettusPlots

Tropical Atlantic SST Anomaly CPC / PettusPlots

Tropical Atlantic SST monitoring focused on the Main Development Region (MDR) — the corridor from the West African coast to the Caribbean (10-20N, 20-80W) where the majority of Atlantic hurricanes form during peak season (Aug-Oct). Warmer-than-normal SSTs in the MDR strongly correlate with more active hurricane seasons.

Atlantic SST Maps

Atlantic Basin SST OISST / PettusPlots

Atlantic Basin SST Anomaly OISST / PettusPlots

Main Development Region SST OISST / PettusPlots

Main Development Region SST Anomaly OISST / PettusPlots

West Atlantic / Caribbean SST OISST / PettusPlots

West Atlantic / Caribbean SST Anomaly OISST / PettusPlots

The Gulf SST OISST / PettusPlots

The Gulf SST Anomaly OISST / PettusPlots

Atlantic Regional SST Indices

Tropical Atlantic SST Anomaly CPC / PettusPlots

North vs South Atlantic SST Anomaly CPC / PettusPlots

Annual SST Comparison

Tropical Atlantic — Annual Overlay CPC / PettusPlots

TC Development Factors

Tropical cyclone development requires more than warm SSTs. Low wind shear, sufficient mid-level moisture, and deep warm water (high ocean heat content) are all critical ingredients. The Saharan Air Layer (SAL) can suppress development by introducing dry, dusty air and increasing shear across the MDR.

Atlantic Tropical Cyclone Heat Potential NOAA AOML

Atlantic Deep-Layer Wind Shear CIMSS

Saharan Air Layer — Split Window CIMSS

Saharan Air Layer — Dust RGB CIMSS

ENSO (El Nino-Southern Oscillation) is the dominant mode of tropical Pacific climate variability. El Nino features anomalously warm SSTs in the central/eastern tropical Pacific, suppressing Atlantic hurricane activity through increased wind shear. La Nina produces the opposite — cooler Pacific SSTs and typically more active Atlantic seasons.

Oceanic Nino Index (ONI)

ONI — 3-Month Running Mean Nino 3.4 Anomaly CPC / PettusPlots

Nino Region SST Anomalies

All Nino Regions CPC / PettusPlots

Nino 3.4 Region Detail CPC / PettusPlots

Nino 3.4 Annual Comparison

Nino 3.4 — Year-over-Year Overlay CPC / PettusPlots

Tropical Pacific SST Maps

Tropical Pacific SST OISST / PettusPlots

Tropical Pacific SST Anomaly OISST / PettusPlots

Nino Region Close-Ups

Nino 3.4 SST Anomaly — Central Pacific OISST / PettusPlots

Nino 3 SST Anomaly — East-Central Pacific OISST / PettusPlots

Nino 4 SST Anomaly — West-Central Pacific OISST / PettusPlots

Nino 1+2 SST Anomaly — Far East Pacific OISST / PettusPlots

Multivariate ENSO Index (MEI v2)

MEI v2 Time Series PSL / PettusPlots

ENSO Forecast & Probability

ENSO Probability Forecast CPC

ENSO Strength Probability CPC

CFSv2 ENSO Forecast Plumes

Nino 3.4 Monthly Plume CFSv2

Nino 3.4 Seasonal Plume CFSv2

Nino 3 Monthly Plume CFSv2

Nino 4 Monthly Plume CFSv2

Nino 1+2 Monthly Plume CFSv2

Global SST Seasonal Forecast CFSv2

CPC Weekly ENSO Diagnostics

Weekly SST Anomalies CPC

Nino Region Anomaly Time Series CPC

SST & Climatology CPC

Tropical Pacific SST Animation CPC

CPC ENSO Discussion Figures

Figure 1 — SST Departures CPC

Figure 2 — SST Anomalies CPC

Figure 3 — Subsurface CPC

Figure 4 — Atmosphere CPC

Figure 5 — OLR CPC

Figure 6 — Forecasts CPC

Figure 7 — Temperature CPC

Figure 8 — Precipitation CPC

MJO Monitoring

The Madden-Julian Oscillation (MJO) is the dominant mode of intraseasonal tropical variability (30-60 day cycle). It modulates tropical convection, wind shear, and can trigger or suppress tropical cyclone development. Active MJO phases over the Atlantic/Caribbean (phases 1-2, 8) tend to favor TC genesis.

MJO Phase Diagram — Last 40 Days CPC

MJO Phase Diagram — Last 90 Days CPC

MJO Forecast CPC

Subsurface ocean temperature structure reveals the full picture of ENSO evolution. Kelvin waves propagate warm/cool anomalies eastward along the equator, and the depth of the 20C isotherm (thermocline) indicates where warm water is pooling. Rising ocean heat content in the central Pacific often foreshadows El Nino development months in advance.

Equatorial Cross-Sections

Equatorial Temperature Cross-Section (Lon vs Depth) CPC

SST Anomaly Cross-Section (5N-5S) CPC

Thermocline (20C Isotherm)

20C Isotherm Depth CPC

20C Isotherm Depth Anomaly CPC

Depth Temperature Anomalies

55m Temperature Anomaly CPC

105m Temperature Anomaly CPC

155m Temperature Anomaly CPC

Temperature Depth Anomaly Animation CPC

Sea Level & Heat Content

Sea Level Anomaly CPC

Upper-Ocean Heat Anomalies (Past Year) CPC

Ocean Heat Content Index

Equatorial Upper 300m Heat Content Anomaly CPC / PettusPlots

MEI Lifecycle

MEI v2 Lifecycle (Current Year) PSL

MEI v2 Lifecycle (All Years) PSL

Hovmoller Diagrams

Hovmoller diagrams show how ocean conditions evolve over time along the equator. They reveal the propagation of Kelvin waves and subsurface warm/cool anomalies — key precursors to ENSO transitions. Eastward-propagating warm anomalies along the thermocline often signal developing El Nino conditions.

Equatorial Subsurface Temperature Anomaly — Hovmoller CPC

Pentad Mean SST (5N-5S) CPC

Surface Current & Wind Anomalies

Equatorial Surface Current Anomaly CPC

Equatorial Zonal Wind Anomaly CPC

NOAA Coral Reef Watch uses satellite SST data to monitor coral bleaching risk worldwide. Degree Heating Weeks (DHW) accumulate thermal stress over 12 weeks — values above 4 indicate significant bleaching likely, above 8 indicates widespread mortality. These products are critical for monitoring marine ecosystem health in tropical waters.

CoralTemp SST Products

Region:

Bleaching Alert Products

OSPO Daily SST OSPO

OSPO Daily SST Anomaly OSPO

HotSpot OSPO

Degree Heating Weeks OSPO

Bleaching Alert Area OSPO