Tropical Waves

A central Atlantic tropical wave has its axis along 54W south of 17N, moving westward at 15 to 20 kt. Scattered moderate convection is seen from 05N to 10N between 50W and 59W.

An eastern Caribbean tropical wave has its axis near 71W south of 15N to inland central Venezuela. It is moving westward at 10 to 15 kt. No significant convection is associated with this tropical wave over the Caribbean.

Monsoon Trough/ITCZ

The monsoon trough axis enters the Atlantic near 16.5N16.5W, then curves southwestward to near 07N25W. The ITCZ extends from 07N25W to 04N37W to 05N49W. Scattered moderate convection is from 04N to 10N and E of 22W, and from 00N to 09N between 36W and 51W.

Gulf Of America

An upper level low over the Bay of Campeche and attendant 1009 mb surface low support scattered moderate to strong convection over the central Gulf. Outside of convection, gentle to moderate or weaker winds and slight seas prevail across much of the Gulf.

For the forecast, the Atlantic ridge extends across Florida into the Gulf region. This system will sustain gentle to moderate E to SE winds through Tue. The exception will be evening pulses of fresh winds off the northern Yucatan and in the central Gulf through the same period. A pronounced deep-layered upper-level trough across the western Gulf combined with a very warm, humid and unstable airmass will continue to support periodic showers and thunderstorms, across the central and eastern Gulf through Sun. Frequent lightning, with gusty winds and locally rough seas are expected in strong thunderstorms. Mariners are urged to keep up to date with the latest forecasts.

Caribbean Sea

An upper level trough is located over SE Mexico while the East Pacific monsoon trough extends across the SW Caribbean. The combined effects from these features are enhancing numerous moderate to strong convection in the SW Caribbean along the coasts of Nicaragua, Costa Rica, and Panama, with more scattered moderate convection occurring along the coasts of Belize and the eastern Yucatan Peninsula. The pressure gradient between high pressure north of the region and the Colombia Low supports fresh to strong trades and 7-9 ft seas across the south-central to SW Caribbean. Moderate to fresh trades and moderate seas prevail across the remainder of the Caribbean.

For the forecast, the pressure gradient between the Atlantic ridge north of the area and the Colombian low will sustain fresh to strong trades and rough seas across the central Caribbean this morning before gradually diminishing in areal coverage this afternoon and evening. Moderate E to SE winds in the Gulf of Honduras are going to pulse to fresh speeds during the night through Tue night. The aforementioned ridge is going to weaken as a couple of frontal boundaries move across the western Atlantic. This will yield moderate to locally fresh winds and moderate seas across most of the basin through Tue, except the south-central Caribbean, where fresh to strong winds and rough seas will persist. Looking ahead, a tropical wave is forecast to reach the Windward Islands by Sat afternoon, leading to increased shower activity.

Atlantic Ocean

A cold front runs along 31N between 68W and 80W. Ahead of the front, generally N of 27N between 45W and 70W, SW winds have increased to fresh to strong speeds while seas are building to 7-10 ft. Scattered moderate convection is occurring N of 28N between 75W and 80W. All other convection across the Atlantic is associated with tropical waves or the monsoon trough/ITCZ. Ridging dominates much of the remaining Atlantic, with moderate to fresh winds and moderate seas prevailing across the vast majority of the basin W of 25W. Areas E of 25W and N of 17N are seeing fresh to strong NE winds and moderate to locally rough seas, confirmed by scatterometer data from this morning. Gentle to moderate or weaker winds and 3-5 ft seas prevail within a ridge axis that extends from just W of the Canary Islands through the central Atlantic and to areas just N of the Bahamas.

For the forecast west of 55W, a ridge over the western Atlantic will support gentle to moderate winds with moderate seas south of 26N through Tue. For the waters north of 26N and east of 70W, two cold fronts migrating eastward across the north Atlantic are going to bring fresh to strong winds along with rough seas through this evening, then again from Sat night through Sun night. Winds may reach near gale force ahead of the second front Sat night through Sun.

Posted 3 hours ago by NHC Forecaster Adams