Marine Weather and Tides
12/16/2019 NOAA is having trouble with requests that include wind gusts. I am posting graphs without wind gusts until it gets fixed.
10/9/2019 Updated the Marine Zones.
9/4/2019 Fixed the weather maps due to NOAA moving them.
7/25/2019 New feature in the Airports section gives a link to 5 minute updates for data reports.
|Sunrise 6:03AM||Sunset 5:40PM||Tuesday January 21, 2020 2:09 PM CST (20:09 UTC)||Moonrise 1:54AM||Moonset 5:00PM||Illumination 12%|
7 Day Forecast for Marine Location Near Pole Ojea, PRHourly EDIT Help
Area Discussion for - San Juan, PR  (on/off)  Help NOTE: mouseover dotted underlined text for definition
FXCA62 TJSJ 211746 AFDSJU
Area Forecast Discussion National Weather Service San Juan PR 146 PM AST Tue Jan 21 2020
SYNOPSIS. The remnants of an old frontal boundary will continue to affect the area tonight and continue on Wednesday under a generally southeasterly steering flow, favoring eastern Puerto Rico and the USVI. By late Wednesday night, a frontal system and associated features will result in an increase in moisture that along with favorable conditions aloft will enhance shower and thunderstorm activity across the forecast area through the weekend and potentially into early next week. A potential for flooding can be expected with this activity.
SHORT TERM. Tonight through Thursday .
Model guidance, as well as recent satellite imagery, suggest that an extended area of low level moisture, associated to a nearly stationary weak frontal boundary, will continue to move in from the southeast and stall over the area through at least Wednesday evening. As a result, a slight increase in shower activity is expected, focused over the USVI and the eastern half of Puerto Rico. Elsewhere, limited shower activity can be expected until a pre-frontal through and associated plume of moisture begins to move in from the southwest. As this feature continues to invade the area and the frontal boundary approaches the region from the northwest, winds are expected to favor a more southerly component through the rest of the short-term period. By late Wednesday night and continuing on Thursday, the combination of a strong low-level convergence, an increase in low-level moisture (GFS suggests precipitable water vapor up to 1.80 inches by Thursday afternoon), and favorable conditions aloft (upper-level polar trough with 500 mb temperatures dropping around -8C) will support a significant increase in shower activity and the potential for isolated thunderstorms across the forecast area. This activity could lead minor flooding and ponding of water on roadways.
LONG TERM. Friday through Tuesday .
PREV DISCUSSION. /issued 504 AM AST Tue Jan 21 2020/
The surface ridge across the Atlantic is forecast to lift farther northeast into the north central Atlantic, as a cold front will move across the western Atlantic and sink southwards across the region. An amplifying mid to upper- level polar trough will also weaken the ridge aloft resulting in a weakening of the trade wind inversion leading to unstable conditions aloft through at least early Friday. The shift in the weather pattern will result good low level moisture pooling and convergence as the frontal boundary sink southwards across the region through Friday. Model guidance remain persistent and suggests a vigorous mid to upper level jet max crossing the region through early Friday. The combination of the instability aloft and good low level moisture convergence will therefore favor the development of scattered to numerous to showers and possibly isolated thunderstorms with periods of locally heavy rains across the region until early Friday.
By late Friday and through the weekend, model guidance suggest lingering low level moisture but gradually improving and stable conditions aloft with a much drier airmass. Therefore expect less frequent early morning shower activity across the islands and coastal waters. This will be followed by isolated to scattered showers of short duration during the afternoon hours. Improving conditions are forecast by Sunday and through Tuesday, as the surface high pressure will once again build and spread across the Atlantic, resulting in a more east northeast wind flow by Monday then a more southeasterly on Tuesday.
AVIATION. Mainly VFR conditions expected across all terminals during the next 24 hours. However, SHRA over NW Puerto Rico may cause tempo MVFR conditions at TJBQ/TJMZ. ESE winds will continue at 10-15 knots.
MARINE. Although the northerly swell and winds continue to subside, hazardous marine conditions will continue through this evening. Thus, Small Craft Advisories continue in effect for most waters except for coastal waters of western and southern Puerto Rico, as well as the Mona Passage. Thereafter, small craft operators are urged to exercise caution due to seas up to 6 feet. Relatively tranquil marine condition will persist through at least late Thursday night, when the arrival of another northerly swell will generate hazardous seas. There is a high risk of rip currents for beaches along the north coast of Puerto Rico, including Vieques and Culebra, as well as Saint Thomas and Saint Croix. The high risk will drop to moderate later tonight.
PRELIMINARY POINT TEMPS/POPS. SJU 73 87 74 84 / 40 40 40 50 STT 73 81 75 81 / 40 40 40 50
SJU WATCHES/WARNINGS/ADVISORIES. PR . High Rip Current Risk through late tonight for Culebra-North Central-Northeast-Northwest-San Juan and Vicinity.
High Rip Current Risk until 6 PM AST this evening for Mayaguez and Vicinity-Vieques.
VI . High Rip Current Risk through late tonight for St Thomas. St. John . and Adjacent Islands.
High Rip Current Risk until 6 PM AST this evening for St Croix.
AM . Small Craft Advisory until 8 PM AST this evening for Anegada Passage Southward to 17N-Atlantic Waters of Puerto Rico and USVI from 10 NM to 19.5N-Caribbean Waters of Puerto Rico from 10 NM to 17N-Coastal Waters of Northern Puerto Rico out 10 NM-Coastal Waters of Northern USVI and Culebra out 10 NM.
SHORT TERM . DS LONG TERM . ICP PUBLIC DESK . LIS
Weather Reporting StationsEDIT (on/off)  Help NOTE: Click on distance to see the station location on a map
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GEOS Local Image of Puerto Rico EDIT
NOTE: East coast views moved to GEOS-16. They are experimental and not well supported by NOAA so they may not be correct so be warned. This change required redoing a large amount of the GOES code. If the image you are expecting is not showing, please let me know. You may need to use the EDIT function to update your location.
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Other links: Northern Pacific Contential US Full GOES-East
Wind Forecast for (15,3,4,5)(on/off)  Help
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