A 1007 mb low pressure center near 58W continues to show signs of organization. Numerous moderate with isolated strong convection is from 15N-22N between 52W-59W. Additional development is expected and a tropical or subtropical depression is likely to form later today or wed while the system moves northwestward and then northward over the open Atlantic. The low is forecast to interact with a frontal system by midweek and further development is unlikely after that time. The chance of tropical cyclone formation within 48 hours is high. This system is forecast to produce winds to gale force by late tonight or early wed morning when the low is moving northward in the general vicinity of 60W. See high seas forecasts issued by the National Weather Service under awips/wmo headers nfdhsfat1/fznt01 kwbc, and online at ocean.weather.gov/shtml/NFDHSFAT1.php for more information.
An Atlantic Ocean tropical wave is along 37W from 12N southward, moving west at 5-10 kt. Scattered moderate to isolated strong convection is from 01N-06N between 35W-43W.
A Caribbean Sea tropical wave is along 70/71W from 20N southward, moving west at 5-10 kt. Isolated showers are within 90 nm on either side of the tropical wave axis from 12N-19N.
The Monsoon Trough extends from the coast of southern Sierra Leone near 12W to 14W. The ITCZ extends from 14W to 21W to 34W. Scattered moderate to strong convection is from 02S-03N between 21W-34W. Scattered moderate to isolated strong convection is from 03N-08N between 11W-20W. Scattered moderate convection is also noted from 05N-10N between 23W-28W.
Gulf of Mexico
Two 1015 mb surface highs are over the western Gulf, near 93W and near 94W, respectively. Weak surface ridging covers most of the Gulf, along with relatively dry air. Weak high pressure over the western Gulf will shift eastward through tonight. Fresh southeast return flow will develop off the Texas coast wed through thu. A strong cold front is expected to move off the Texas coast fri afternoon, resulting in fresh to strong northerly winds behind it. The front will rapidly move across the basin, nearly exiting by late sat night.
A stationary front passes through the Atlantic Ocean, from 70W to the windward passage near 75W. A surface trough continues to the eastern coast of Jamaica to 78W to 81W. Isolated moderate convection is from 19N-22N between 70W-77W in parts of Hispaniola and the windward passage. Broken multilayered clouds and possible rainshowers are to the west and northwest of the surface trough. The latest ascat pass shows moderate north winds to the west of the surface trough over the western Caribbean, and fresh along the coast of Nicaragua. The trough will dissipate tonight. The tropical wave along 71W will weaken through tonight and early wed.
See the special features section above for information on the low pressure near 58W, which has a high chance of tropical or subtropical cyclone formation during the next 48 hours.
A surface trough extends from 70W to near nassau Bahamas with isolated showers possible east of the trough axis. A cold front passes through 61W to 65W. The front becomes stationary from 65W to 70W to the windward passage near 75W. Scattered moderate convection is near the cold front. Isolated moderate convection is near the stationary front from 19N-22N between 70W- 77W in parts of Hispaniola and the windward passage. Surface high pressure ridging covers the Atlantic elsewhere east of 55W, anchored by a 1030 mb high near 38W. Trade winds of 20-25 kt cover the Atlantic from 15N-25N between 20W-45W.
Seas west of the west Atlantic stationary front, north and northeast of the Bahamas, will continue to gradually subside through early this evening. A trough behind the stationary front will generate into a cold front and sweep across the rest of the western and central forecast waters this afternoon through wed night. Fresh to strong west to northwest winds and building seas will follow in behind this front. High pressure will build across the northern waters thu through sat. Yet another cold front may move off the northeast Florida coast late sat night. Fresh to strong southwest winds are forecast to develop over the far northwest waters beginning on sat afternoon.
Posted 1 hour, 59 minutes ago by NHC Forecaster Hagen