Winthrop Harbor Buoy, IL
Illinois, United States
Last wave reading:
Last reading
This reading is more than 3 hours old. The buoy may have stopped sending waves for now.
Significant wave height at the buoy
1.0 ft
0.3 m
- Dominant period
- 3 s
- Direction
- from SSE 156°
This reading came without the swell and wind-wave split, so the numbers are for the whole sea.
Short-period wind chop: 1.0 ft at 3 s from the SSE.
Significant wave height is the average of the biggest third of waves at the buoy. It is not surf height at a beach.
Trend at the buoy
Height at the buoy
- Total (significant height)
Period
- Dominant period
Hourly means of the buoy's readings. Arrows point the way the waves travel.
Model vs the buoy
- Buoy, hourly
- Model, past days
- Model forecast
| Day | Height | Peak period | From |
|---|---|---|---|
| Fri, Nov 13 | 6.3 ft | 7.6 s | NNE |
| Sat, Nov 14 | 5.0 ft | 6.9 s | NNE |
| Sun, Nov 15 | 1.8 ft | 5.8 s | NNE |
| Mon, Nov 16 | 0.8 ft | 2.4 s | S |
| Tue, Nov 17 | 1.2 ft | 3.2 s | SSE |
| Wed, Nov 18 | 1.9 ft | 3.7 s | SSE |
| Thu, Nov 19 | 1.9 ft | 4.1 s | SSE |
ECMWF WAM wave model via Open-Meteo, nearest model cell (42.500°N, 87.750°W). Both lines are significant wave height at sea, the same measure the buoy reports. Model output, not a Quiver beach forecast.
Nearby buoys
- Waukegan Buoy, IL1.3 ftStale · 14 km
- Salmon Unlimited WisconsinOffline · 26 km
- Wilmette Buoy, IL0.7 ftStale · 41 km
- South Michigan Spotter6.6 ft · 6 sLive · 65 km
- ATW20 - Atwater Park, WI6.2 ft · 8 sLive · 68 km
- Chicago Buoy0.7 ftStale · 69 km
Other readings
- Water temperature
- 61°F (16.0°C)
- Wind
- 14 kt, gusts 21 kt
- Air temperature
- 62°F (16.6°C)
- Pressure
- 1019.5 hPa
Reported Oct 14, 11:50 AM CDT.
How to read this buoy
Biggest hourly reading in that record: 1.0 ft at 3 s on Oct 13.
- Station id
- 45187
- Operator
- University of Illinois at Urbana-Champaign
- Program
- IOOS Partners
- Position
- 42.491°N, 87.779°W
- Type
- Moored buoy
- Local time zone
- America/Chicago
- Swell split
- Yes, swell and wind waves reported
Source: NOAA National Data Buoy Center (NDBC); station operated by University of Illinois at Urbana-Champaign. Licence: Public domain (US government work). Station page at the source.
Not for navigation. Readings can be late, missing or wrong; check official marine forecasts before going to sea.
Buoy terms
- Significant height
- The average of the biggest third of waves the buoy measured. Sets in the surf zone can be bigger or smaller.
- Dominant period
- Seconds between the waves carrying the most energy. Longer period means more power and more bend around points.
- Swell vs wind waves
- Swell was made by distant wind; wind waves were made nearby. The buoy splits its spectrum at a cutoff period to report each.
- Direction
- Where waves come from, in degrees true. 270° is from the west.
