Hurricane Larry Becomes Atlantic’s 3rd Major Hurricane For 2021

Hurricane Larry has continued to strengthen well east and northeast of the Lesser Antilles over the last several days, becoming the Atlantic’s 3rd major hurricane for 2021. Larry is a major Category 3 hurricane, with sustained winds of 205 KM/H.

Larry is forecast to slowly move to the west-northwest, then northwest through the next three days with no direct threat to Trinidad, Tobago, and the remainder of the Lesser Antilles.

However, Larry will weaken the pressure gradient across the region and allow for light winds and relatively high humidity causing very hot temperatures through the upcoming week across the region. For Trinidad and Tobago, as well as parts of the Southern Windwards, a trough induced by Hurricane Larry will allow for occasional cloudiness, showers, and isolated thunderstorms from late Sunday through Tuesday as the hurricane also brings the ITCZ northward.

In addition, with light winds, funnel cloud and waterspout development will be likely, favoring western areas of Trinidad, Tobago, and the Southern Windwards.

Lastly, swells from Hurricane Larry are forecast to begin affecting the entirety of the Lesser Antilles from Sunday. A Hazardous Seas Alert (Yellow Level) will be in effect for T&T from 2:00 AM Sunday from the Trinidad and Tobago Meteorological Service.

The Latest From The National Hurricane Center

Hurricane Larry’s Forecast Track as of 11:00 PM Saturday 4th September 2021. (National Hurricane Center)

At 11:00 PM AST, the center of Hurricane Larry was located near latitude 18.0 North, longitude 48.0 West. Larry is moving toward the west-northwest near 22 KM/H. A turn toward the northwest is expected overnight, with Larry maintaining that heading at gradually slower speeds through Tuesday.

Maximum sustained winds are near 195 KM/H with higher gusts. Larry is a category 3 hurricane on the Saffir-Simpson Hurricane Wind Scale. Little change in strength is forecast during the next few days, although fluctuations in intensity will be possible. Larry is expected to remain a major hurricane through the middle of next week.

Hurricane-force winds extend outward up to 75 kilometers from the center and tropical-storm-force winds extend outward up to 260 kilometers. The estimated minimum central pressure is 958 millibars.

Hurricane Larry’s Watches & Warnings

There are no tropical storm or hurricane watches or warnings in effect for any coastal areas at this time.

However, a high surf advisory goes into effect for Montserrat, St. Kitts, Nevis, Anguilla, and the British Virgin Islands from Sunday night. A high surf warning goes into effect for Antigua and Barbuda from Sunday night while a high surf warning goes into effect for Anguilla and the British Virgin Islands from Monday.

Small craft operators and sea bathers in St. Lucia are advised to exercise caution.

In Trinidad and Tobago, a Hazardous Seas Alert (Yellow Level) is in effect for T&T from 2:00 AM Saturday 5th September 2021 to 12:00 PM Friday 10th September 2021.

Hurricane Larry: Hazards Affecting Land

Hurricane Larry’s probabilities for tropical-storm-force winds as of 11:00 PM Saturday 4th September 2021. (National Hurricane Center)

SURF: Swells generated by Larry are expected to reach the Lesser Antilles on Sunday, and will spread westward to portions of the Greater Antilles, the Bahamas, and Bermuda Monday and Tuesday. Significant swells will likely reach the east coast of the United States and Atlantic Canada around midweek. These swells are likely to cause life-threatening surf and rip current conditions. Please consult products from your local weather office.

Hurricane Larry’s probabilities for hurricane-force winds as of 11:00 PM Saturday 4th September 2021. (National Hurricane Center)

This system is of no direct threat to Trinidad and Tobago.

Hurricane Larry’s Forecast Discussion

Hurricane Larry (Weathernerds.org)

Larry has developed a large eye this evening that is 40-45 nautical miles in diameter, and the surrounding cloud tops have warmed somewhat. There has been no microwave passes over the hurricane for quite some time to assess its structure, but conventional satellite images suggest that Larry has taken on some annular characteristics (and the objective screening algorithm tagged it as marginally annular). Dvorak CI numbers and objective estimates are all between 100-102 knots, so Larry’s initial intensity is lowered slightly to 105 knots.

Larry’s motion remains west-northwestward (300 degrees) at 12 kt. The hurricane is expected to turn northwestward tonight or early Sunday around the southwestern periphery of a mid-level high centered over the central Atlantic, and then maintain that heading with some decrease in forward speed through day 4. By day 5, Larry should turn northward and accelerate between the high and an approaching deep-layer trough over the eastern United States. The updated NHC track forecast is largely unchanged from the previous advisory and is of high confidence since there is a lower-than-normal spread among the track models. Larry is forecast to make its closest approach to Bermuda in 4 to 5 days while it recurves around the ridge, but despite the high-confidence forecast, there is still uncertainty on how close that approach will be since several GEFS and ECMWF ensemble members bring Larry’s center very close to or over the island. Even with a track east of the island, Larry will be large enough to possibly cause some impacts on Bermuda.

Water vapor imagery shows some restriction to the outflow in the southwestern quadrant, which could be indicative of some shear. There continues to be some discrepancy among the models on how much shear the hurricane will contend with as it approaches a mid-/upper-level trough located north of the Leeward Islands. The GFS keeps the shear over Larry fairly low since it’s farther from the trough, while the ECMWF increases the shear to moderate or strong levels during the next 48 hours. If Larry reaches the area of stronger shear, its intensity would obviously be adversely affected. In terms of structure, significant re-intensification is now less likely since Larry has such a large eye and an expanding wind field. On the positive side, the hurricane will be moving over gradually warmer waters for the next 3 days or so. Given these conflicting factors, the updated NHC intensity forecast allows for some slight restrengthening in the short term but then keeps Larry’s intensity steady for the next 3 days. Many of the intensity models are even lower than what’s shown in this forecast, so additional adjustments may be required in future advisories.

Key Messages:

  1. Large swells generated by Larry are expected to first reach the Lesser Antilles on Sunday and will spread to portions of the Greater Antilles, the Bahamas, and Bermuda Monday and Tuesday. Significant swells will likely reach the east coast of the United States and Atlantic Canada around midweek. These swells will likely cause life-threatening surf and rip current conditions, and beachgoers and other interests along these coasts are urged to follow the advice of lifeguards and local officials through the upcoming week.
  2. Larry is forecast to approach Bermuda during the next several days, possibly as a major hurricane, bringing a risk of strong winds, heavy rainfall, and coastal flooding to the island by the middle of next week. While it is too soon to determine the magnitude of these hazards and potential impacts on Bermuda, interests there should monitor changes to the forecast during the next several days.
Facebook Comments