CBEFS
Chesapeake Bay Environmental Forecast System
Use our forecasts and "nowcasts" of temperature, salinity, dissolved oxygen, and other physical and chemical factors within the Chesapeake Bay to help monitor Bay health and plan your on-the-water activities. Based on observations and computer models developed by the Virginia Institute of Marine Science and partners, these tools accurately predict the current status of important environmental variables and how they are likely to change in the short-term.
Our Chesapeake Bay Environmental Forecast System simulates 3 conditions for each selected variable:
- Nowcast: present-day status of selected variable in Chesapeake Bay
- 2-Day Forecast: status of selected variable in the Bay 2 days from now, and
- Forecast Trend: difference between nowcast and forecast (% change over 2 days)
Click a selection below to access the specified simulation. Please see the contact information page for data requests and general contact information.

Dissolved Oxygen (DO)
Discover when and where low-oxygen "dead zone" conditions may form.

Dead Zone Size
Track "hypoxia" in the Bay, as measured by the volume of waters where DO levels are below 2 mg/L.

Depth to Low Oxygen
Find the depth to fish-unfriendly waters where dissolved oxygen levels fall below 3 mg/L.

Hypoxia through Time
View DO levels through time to understand the seasonal cycle in the Chesapeake Bay.

Acidification
Maps and line-plots of acidification metrics such as pH in the Bay and its lower tributaries

Bay Salinity
View salinity through time to understand its seasonal and weekly changes in the Chesapeake Bay.

Bay Temperature
View temperature through time to understand its seasonal and weekly changes in the Chesapeake Bay.

Tributary Salinity
View a close-up of surface salinity in the James, York, and Rappahannock rivers.

Tributary Temperature
View a close-up of surface temperature in the James, York, and Rappahannock rivers.

Sea Nettles
Discover your chance of seeing sea nettles based on forecasts of salinity and water temperature.

Harmful Algal Blooms
View an experimental forecast of your likelihood of encountering a Harmful Algal Bloom.