Heavy Rainfall in Central America
A central American gyre has developed in the eastern north Pacific Ocean. The gyre will move northward, gradually, toward Central America and southern Mexico, during the upcoming weekend. The gyre will continue to push abundant moisture into parts of Central America through the weekend, and into the next week. Heavy rainfall is likely in Central America, especially from northern Costa Rica northward into southern Mexico. Heavy rainfall will bring the potential for life-threatening flash floods and mudslides for the locations that receive the greatest amounts of rainfall, especially in the areas of mountainous terrain. Please read the bulletins and forecasts from your local weather service for more information.
Broad Low Pressure in the Atlantic Ocean
A 1016 mb low pressure center is in the central Atlantic Ocean near 57W. An upper level cyclonic circulation center is near 59W. Precipitation: scattered moderate to strong is from 100 nm to 200 nm northwest of the center in the northwest quadrant. Isolated moderate to locally strong is elsewhere within 300 nm of the center. Additional development of this system is possible, and a subtropical depression may form today, as the low pressure center moves generally northward. The organization of the low pressure center has not changed substantially during the past several hours. More development is not expected by tonight due to unfavorable environmental conditions. The next special tropical weather outlook will be issued by 9 a.m. EDT today, or earlier, if necessary. The chance of formation into a tropical cyclone during the next 48 hours is medium. Please read the tropical weather outlook, https://www.nhc.noaa.gov/gtwo.php?basin=atlc&fdays=2, for more details.
A tropical wave is in the Caribbean Sea, along 80W, from 20N southward, moving westward 15 knots. Precipitation: isolated moderate has been in the southwest corner of the Caribbean Sea, during the last 24 hours, in an area of broad surface low pressure. The tropical wave will move through the western Caribbean Sea during the next two days, then absorbed into the central American gyre.
The Monsoon Trough passes through the coastal sections of Guinea near 15W, to 21W, to 26W, and to 29W. The ITCZ continues from 29W, to 42W. Precipitation: scattered moderate to isolated strong from 03N to 04N from 04W eastward, from Africa southward between 04W and 08W, and from 05N to 08N between 20W and 24W. Widely scattered moderate to isolated strong is from the ITCZ to 09N between 24W and 40W. Isolated moderate is elsewhere from 10N southward from 60W eastward.
Gulf of Mexico
A cold front is passing through central Alabama and southern Mississippi, to southeast Louisiana. Precipitation: rain showers are possible within 60 nm on either side of the front.
An upper level trough extends from interior sections of Mexico into the southwest corner of the Gulf of Mexico. Precipitation: widely scattered to scattered moderate and isolated strong is from 26N southward from 85W westward. Areas of precipitation have been forming in the southwest Gulf of Mexico during the last 6 to 9 hours or so, followed by warming cloud top temperatures and dissipating precipitation, followed by more areas developing precipitation.
The tail end of the cold front will move into the northern Gulf of Mexico on Sunday and Monday. The front will then stall and dissipate in the east central Gulf of Mexico by late Tuesday. It is possible that the wind speeds and the sea heights may increase in the southwest Gulf of Mexico by mid-week, as low pressure forms more to the south.
Please read the special features section, for more information about the potential for heavy rainfall in Central America, during the next few days.
Broken to overcast multi-layered clouds and remnant showers, are in the northwest Caribbean Sea, related to what has been moving from the Yucatan Peninsula, into the northwest corner of the Caribbean Sea, from the southwest Gulf of Mexico upper level trough and clouds and precipitation.
Broad upper level anticyclonic wind flow covers the Caribbean Sea from 70W westward. Upper level cyclonic wind flow covers the rest of the Caribbean Sea. The upper level wind flow is at the southern end of the upper level trough that extends from the central Atlantic Ocean, southwestward. This is the same upper level trough that is near the 1015 mb Atlantic Ocean low pressure centered near 56W.
The tropical wave that is south of central Cuba will move across the western Caribbean Sea through Sunday. The wind speeds and the sea heights will increase in the Gulf of Honduras, early next week, as broad low pressure forms in the northern sections of Central America and southern Mexico.
Please read the special features section, for more information about the 1015 mb low pressure center that is near 56W. The chance of formation into a tropical cyclone during the next 48 hours is medium.
Upper level cyclonic wind flow covers the Atlantic Ocean from 22N northward from 36W eastward. No significant deep convective precipitation is apparent in satellite imagery.
Weak high pressure to the north of the area will shift eastward through Sunday. The area of high pressure will move eastward, in advance of a cold front that is forecast to move to the south of 30N Sunday night. The front will reach from Bermuda to palm beach Florida on Monday. The front will stall, and dissipate along 25N through mid-week.
Posted 28 minutes ago by NHC Forecaster Mt/Dbm