The Hazardous Seas Alert
As we’ve mentioned yesterday, rough seas are forecast to begin affecting Trinidad and Tobago by late Thursday, with a Hazardous Seas Alert now being issued.
At 1:51 PM on Wednesday, the Trinidad and Tobago Meteorological Service has now issued a Hazardous Seas Alert for all coastlines of Tobago, Northern, Eastern and Southeastern coastlines of Trinidad and Eastern and Northern offshore waters. The alert will go into effect at 8:00 PM Thursday 9th January 2020 through 2:00 PM Tuesday 14th January 2020.
Note that this alert will likely be upgraded to a warning on Friday as rough seas materialize and may also be extended beyond Tuesday as strong low-level winds are forecast to continue agitating seas.
Trinidad and Tobago is NOT under any tropical storm threat, watch or warning.
Based on the latest model guidance and analysis, long period swells are ongoing through next Tuesday. The effects will be exacerbated by ongoing spring tides. Elevated tides are ongoing due to Full Moon occurring on Friday 9th January, with elevated tides ongoing through Monday 13th January.
Generally, battering waves in nearshore areas are forecast to continue through Tuesday, particularly during high tide periods. Coastal flooding is also likely in low-lying coastal areas, which will be enhanced by Spring Tides. Beach and coastal erosion are likely, particularly along Northern and sheltered coastlines. Overall, there is a high risk of rip currents and large waves at beaches through next week so disruptions to beachgoers and marine interests are expected.
Information from the Trinidad and Tobago Meteorological Service concerning the Hazardous Seas Alert for January 8th to January 14th, 2020.
“Strong low-level winds are expected to agitate sea conditions, mainly around Tobago and to the North and East of Trinidad. Waves are expected to reach heights between 2.5 m and 3.2 m in open waters.” according to the Trinidad and Tobago Meteorological Service. This “alert” status takes into account the possibility of the event occurring. This hazardous seas event is likely.
The color of the alert indicates the severity of the event and the probability of the event occurring. Currently, the alert level is at Yellow. This means that the hazard is likely and you need to be aware of the impacts of hazardous seas in your area. Moderate impacts are expected, so there is the chance of possible injuries and persons would need to take action to ensure safety. There may be minor damage to property.
7-Day Sea Forecast
Rough and hazardous seas are forecast to begin on Thursday as a strong high-pressure system is forecast to build across the entire region, bringing strong low-level winds between 20 to 25 knots (37-46 KM/H), up to 30 knots (56 KM/H) and gusts to 60 KM/H.
Strong low-level winds will agitate coastal waters, predominantly eastern coastal areas of Trinidad and all coastal areas of Tobago Thursday through much of next week, as models indicate hazardous seas continuing through next Wednesday. Waves may reach in excess of 3.5 meters, up to 4.0 meters in open waters, particularly in Eastern Coastal waters.
In addition, long period swells (with 11-15 second periods) are forecast to begin affecting T&T’s coastal waters, originating from the North and Northeast. These swells will mainly affect Northern, Eastern, and Western coastal waters of both islands between Wednesday 8th January and Monday 13th January, possibly extending into next week.
The general sea state through the next 7 days is as follows:
Thursday 9th January 2020: Moderate to occasionally rough, with waves up to 2.5 meters throughout the day, nearing 3.0 meters by nightfall. Long-period northerly swells are forecast to persist. Winds will be between 20-25 knots from the east to northeast. In sheltered areas, waves are forecast to be near 1.0 meters, occasionally reaching 1.5 meters and choppy. Spring Tides ongoing.
Friday 10th to Saturday 11th January 2020: Rough, with waves generally between up to 3.0 meters in open waters, occasionally up to 3.5 meters. Waves, in further eastern coastal areas, may reach up to 4.0 meters. In sheltered areas, near 1.0 meters, occasionally up to 1.5 and choppy. Long Period Swells ongoing. This is the initial peak of this rough seas event.
Sunday 12th January 2020: Moderate to occasionally rough, with waves up to 2.5 meters throughout the day, nearing 3.0 meters by nightfall. Long-period northerly swells are forecast to persist. Winds will be between 20-25 knots from the east to northeast. In sheltered areas, waves are forecast to be near 1.0 meters, occasionally reaching 1.5 meters and choppy. Spring Tides ongoing.
Monday 13th to Tuesday 14th January 2020: Rough, with waves generally between up to 3.0 meters in open waters, occasionally up to 3.5 meters. In sheltered areas, near 1.0 meters, occasionally up to 1.5 and choppy. Long Period Swells ongoing. This is the secondary peak of this rough seas event.
Both the effects of long-period swells and rough seas due to strong low-level winds will be amplified by the effect of Spring Tides as Full Moon will occur on the Friday 10th January 2020 and a Lunar Perigee (moon closest to Earth) will occur on Monday 13th January 2020.
Approximate high tides for Port of Spain, Trinidad, and Scarborough, Tobago are seen below. Low-lying coastal areas may experience coastal flooding, particularly 30 minutes prior and 30 minutes after when peak high tides occur.
Marine interests are advised to prepare for adverse sea conditions and beachgoers are advised to refrain from heading to bays and beaches beginning late Thursday.
Impacts on T&T’s Shorelines
Impacts possible from rough seas include the following:
- Loss of life;
- Sea search and rescue disruptions;
- Disruptions to sea transportation;
- Scarcity of seafood;
- Damage or loss of boats and fishing equipment;
- Disruptions to marine recreation and businesses
- Economic losses.
Other impacts from the high winds, apart from hazardous seas, include:
- Coastal erosion;
- Localized disruptions of businesses;
- Disruption to outdoor and sporting activities;
- Disruption of transportation (air and especially sea) and
Wind of this strength could make some outdoor activities uncomfortable, if not outright dangerous. High winds can create dangerous fallen or blowing objects.
The strongest winds and the highest and most dangerous seas will begin on Thursday. The highest seas will take place in the Atlantic waters of the islands.
There is also the potential for loss of life. There is a high risk of rip currents, strong currents that can carry even the strongest swimmers out to sea.
Rip currents are powerful channels of water flowing quickly away from the shore, which occur most often at low spots or breaks in the sandbar and near structures such as groins, jetties, and piers. If caught in a rip current, relax and float. Don’t swim against the current. If able, swim in a direction following the shoreline. If unable to escape, face the shore and call or wave for help.
There is also the potential for injuries to beachgoers; beach closures; localized disruptions to marine recreation and businesses and financial losses.
High tides combined with onshore wind and swell actions could result in localized coastal flooding and beach erosion.
High surfs can knock spectators off exposed rocks and jetties. Breaking waves may occasionally impact harbors making navigating the harbor channel dangerous.
Saltwater will likely splash onto low-lying coastal roads such as the South Trunk Road at Mosquito Creek, the Guayaguayare Mayaro Road at the Guayaguayare Sea Wall, and the Manzanilla-Mayaro Road. Bays and beaches may become inundated.
Coral reefs may experience increased stress and damages, in addition to localized beach erosion, particularly in areas where battering waves focus.
Note that for those still heading to the beaches, particularly along Eastern coastlines, a significant amount of seafoam may be whipped up due to strong winds.