Tidewatch 3.0 Forecasts
Tidewatch 36-Hour Time Series Forecasts
Tidewatch Charts © are 36-hour time series forecasts of storm tide predictions in and around Chesapeake Bay. Tidewatch Charts rely on an ensemble of local, state, and federally-operated networks of tide gauges sharing real-time water level monitoring data. Tidewatch’s 36-hour forecast algorithm discretizes the tidal components of amplitude, phase, and frequency through site-specific harmonic analysis to help serve as a reliable coastal flooding decision-support system. Tidewatch sets itself apart from other forecasting systems through integration of recent water-level observations and assimilation of a 30-day monthly mean as a moving window (m30 signal). These inputs combine with local surge guidance from hydrodynamic modeling to estimate flood magnitude, timing, and extrapolated spatial extents at site-specific locations throughout the Chesapeake Bay and Virginia’s seaside Eastern Shore.
Tidewatch 3.0 represents an upgrade from the original 1.0 version released in 2011 by VIMS Emeritus Professor John Boon running on automated Matlab scripts based upon the Hamels Tide code included in the appendix of his book, Secrets of the Tide. Tidewatch 2.0 was released in 2018, and expanded the total number of tidal constituents used in Tidewatch's harmonic prediction algorithm, and the source of real-time tide gauges beyond NOAA sites to also include USGS and StormSense sensors.
Tidewatch 3.0 expands upon Tidewatch's forecasting approach by:
- Updating the code base from Matlab to Python, and increasing the total number of harmonic constituents used for each site to 16
- Allowing users to directly download all 6-minute interval data in CSV format (including metadata)
- Providing dynamic, interactive plots of 36-hour forecasts, along with 3-day, and 30-day hindcasts
- All sites provide real-time observations and predictions relative to two separate datums:
- Mean Lower Low Water (MLLW - tidal datum; relevant for boat navigation)
- North American Vertical Datum (NAVD - geodetic datum; relevant to land flooding thresholds)
Tidewatch Charts present 36-hour time series predictions with hourly update intervals throughout the Chesapeake Bay at 65 locations (this site is continually being updated to add more forecast locations), consisting of:
- 10 NOAA-operated tide gauges,
- 17 USGS-operated tide gauges,
- 13 VDEM-operated tide gauges,
- 25 StormSense-operated tide gauges
A related observational dataset, VIMS’ StormSense network, expands Tidewatch’s relevance inland by incorporating data from water-level sensors deployed in flood-prone coastal and near-coastal environments where tidal forcing is attenuated. These sensors enhance situational awareness in areas not well represented by traditional tide gauges.
A Comprehensive Inventory of Tide Gauges near Virginia with 36-Hour Tidewatch Storm Tide Time Series Forecasts
NOAA
1. Sewells Point
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Station: SWPT |
2. Yorktown
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Station: YRCG |
3. Windmill Point
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Station: WMPT |
4. Lewisetta
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Station: LEWI |
5. Bishops Head
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Station: BISH |
6. Dahlgren
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Station: DAHL |
7. Washington DC
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Station: WADC |
8. Kiptopeke
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Station: KIPT |
9. Wachapreague
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Station: WACH |
USGS
1. Jamestown
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Station: USJT |
2. Brick Kiln Creek
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Station: USBK |
More Stations Coming Soon
StormSense
1. Chickahominy River at Mamanahunt (VIMS)
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Station: GS01 |
2. Pamunkey River at Lay Landing Rd (VIMS)
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Station: GS02 |