CHANGES WITH THIS ADVISORY:

A Tropical Storm Watch has been issued for the northern coast of Honduras from Punta Patuca westward to the GuatemalaHonduras border, including Roatan Island and the Bay Islands of Honduras.

SUMMARY OF WATCHES AND WARNINGS IN EFFECT:

A Tropical Storm Watch is in effect for...
- Northern Honduras
- Roatan Island and the Bay Islands of Honduras

A Tropical Storm Watch may be required for portions of Guatemala, Belize, and the southern Yucatan Peninsula later today.

A Tropical Storm Watch means that tropical storm conditions are possible within the watch area, generally within 48 hours.

For storm information specific to your area, please monitor products issued by your national meteorological service.

WIND: Tropical storm conditions are possible within the watch area by late Wednesday.

RAINFALL: Rainfall amounts of 2 to 3 inches will be possible over the northern portions of Honduras beginning late Wednesday.

SURF: Swells generated by this system are affecting portions of the southern coast of Jamaica, and will continue into Wednesday morning. These swells are likely to cause lifethreatening surf and rip current conditions. Please consult products from your local weather office.

At 1100 AM EDT (1500 UTC), the disturbance was centered near latitude 16.1 North, longitude 77.5 West. The system is moving toward the west near 18 mph (30 km/h), and this general motion is expected to continue through Thursday. On the forecast track, the system will be moving near but north of the coast of Honduras on Wednesday.

Maximum sustained winds are near 40 mph (65 km/h) with higher gusts. Some strengthening is forecast during the next 48 hours. Additional development is expected today and on Wednesday, and a tropical depression or tropical storm could form at any time. * Formation chance through 48 hours...high...90 percent * Formation chance through 5 days...high...90 percent

Tropicalstormforce winds extend outward up to 80 miles (130 km), mainly northeast through northwest of the center.

The estimated minimum central pressure is 1005 mb (29.68 inches).

An Air Force Reserve reconnaissance aircraft is currently investigating the vigorous tropical disturbance located south of Jamaica that the NHC has been tracking the past few days across the Caribbean Sea. An earlier report of 35 kt winds this morning from ship MAOR4 is the basis for the 35-kt initial intensity on Potential Tropical Cyclone Sixteen. (PTC-16)

The initial motion estimate is an uncertain 285/16 kt, based mainly on past scatterometer surface wind data and passive microwave satellite fix data. A strong deep-layer to the north of the system is expected to build slowly westward over the next few days, keeping the disturbance moving in a general west-northwestward to westward direction through 48 hours, followed by a turn toward the west-southwest shortly thereafter when the system will be inland over Central America. The NHC official forecast track lies close to a blend of the simple consensus models TVCN and GFEX, and the corrected-consensus model HCCA.

The disturbance has already developed an upper-level anticyclone, with outflow only restricted in the northeastern quadrant due to northeasterly shear of about 15 kt. This modest northeasterly to easterly vertical wind shear is expected to gradually subside to less than 10 kt by 48 hours, which should allow for at least some slow but steady strengthening, given that sea-surface temperatures (SST) will be 29.5-30.5 deg C along the track. Occasional intrusions of dry mid-level air might hinder development for the next 24-36 hours, but model guidance shows that the atmosphere is expected to moisten thereafter and right up until landfall. The official intensity forecast is similar to the consensus of the intensity guidance through 24 hours, and then is a little above the consensus at 36 h and 48 h due to the very warm waters, moistening atmosphere, and low shear conditions. The statistical SHIPS guidance suggests that the cyclone could reach hurricane strength just prior to landfall. This alternate scenario will be evaluated on the next advisory cycle.

Due to the system's expected proximity to the north coast of Honduras and Roatan Island, a Tropical Storm Watch has been issued for those areas. Additional watches and possible warnings will likely be required later today for Guatemala, Belize, and the southern portion of the Yucatan Peninsula.