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 6:25AM||Sunset 6:48PM||Thursday April 2, 2020 9:09 PM AST (01:09 UTC)||Moonrise 1:24PM||Moonset 2:03AM||Illumination 75%|
7 Day Forecast for Marine Location Near Rinc�n, PRHourly EDIT Help
Area Discussion for - San Juan, PR  (on/off)  Help NOTE: mouseover dotted underlined text for definition
FXCA62 TJSJ 030059 AFDSJU
Area Forecast Discussion National Weather Service San Juan PR 838 PM AST Thu Apr 2 2020
UPDATE. Fair weather conditions prevailed across the CWA with only a few showers observed over sections of northwestern puerto Rico in the afternoon hours. For the overnight hours, dry and quiet weather pattern will continue across the regional area. However, some brief showers still posibles over the local waters. For tomorrow, some passing showers are expected for eastern sections of Puerto Rico an the USVI. In the afternoon hours, the showers are expected to develop over sections of north central and interior sections of the island. Low temperatures in the night hours will range between the low to mid 70s across coastal areas, and low to mid 60s across higher elevations. Above- normal daytime high temperatures are expected once again on Friday afternoon due to a southeasterly wind flow.
AVIATION. Mainly VFR conditions expected across the local terminals during the next 24 hours. Winds will be light and variable through 03/12Z, increasing between 7 to 10 knots and favoring a southeasterly flow with sea breeze variation thereafter.
MARINE. Fairly tranquil marine conditions with seas between 1 and 4 feet will prevail across the regional waters through at least Friday afternoon. A northerly swell are expected to invade the local and Atlantic waters and will deteriorate the marine conditions by Friday evening into the weekend. Therefore, a Small Craft Advisory is in effect for the offshore Atlantic waters by Friday evening. There is a moderate risk of rip currents for beaches along the north coast of Puerto Rico and Culebra. The risk will elevate to high by Friday morning for beaches along the north central coast of Puerto Rico, and by Friday afternoon for the remaining beaches along the north, east and half- west coast of Puerto Rico.
PREV DISCUSSION. /issued 419 PM AST Thu Apr 2 2020/
SYNOPSIS . Fair and dry weather conditions will dominate the local area through at least Friday, before a frontal boundary approach the area and increase the potential for shower activity during the weekend into early next week. Warmer temperatures expected through at least Saturday under a southeasterly wind flow. Marine conditions are expected to deteriorate by Friday evening into the weekend with the arrival of a northerly swell.
SHORT TERM . Tonight through Saturday .
For tonight, an area of showers across the eastern Caribbean Sea should reach portions of St. Croix and southern Puerto Rico through Friday morning. Minor rainfall accumulations are anticipated with this activity. During the afternoon hours, this surge in moisture and a south to southwesterly steering wind flow will aid in the development of afternoon showers over portions of the interior and northern Puerto Rico. Hi-res models continue to suggest mostly minor to moderate rainfall amounts.
Meanwhile, a broad surface low over the northwestern Atlantic is supporting a cold front that is currently moving across eastern Cuba. The surface low is expected to sink southwards on Saturday and move into the central Atlantic by Sunday, this will bring the front to our area later in the weekend and create light and variable winds by late Friday night and through the short term period. An upper level jet will provide divergence aloft on Saturday and as the front moves over the local Atlantic waters, shower activity will continue through Saturday night across the northern half of Puerto Rico and the northern USVI.
LONG TERM . Sunday through Friday .
FROM PREV DISCUSSION . /issued 436 AM AST Thu Apr 2 2020/
A long-wave mid to upper level trough will continue to be the dominant weather feature across the western Atlantic early in the forecast period, while it will begin to move away, toward the central Atlantic by mid-week. At the surface on Sunday and Monday, a frontal boundary near the area and a surface high pressure over the eastern Atlantic will result in an area of low level convergence that will drag moisture into the islands. Precipitable water values are expected to range between 1.3 to 1.5 inches these days. Additionally, at the upper levels, a piece of the jet stream will be located north of the islands, hence increasing somewhat instability aloft. That said, conditions appear to be more conducive for an increase in showers across the islands. Under a light wind flow across the islands, this activity could be slow-moving, and might result in urban and small stream flooding across the area.
By the latter part of the long-term forecast period, as the long- wave trough moves toward the Central Atlantic, conditions are expected to become less favorable for any significant rainfall activity to occur. However, at the lower levels, moisture and low level convergence remains. Therefore, groups of showers may affect the area early in the morning hours across the coastal areas, while in the afternoon, supported by diurnal effects, additional showers may develop as well.
AVIATION . VFR conditions will continue to prevail at most terminals today, with the only exception being TJMZ/TJBQ where enhanced cloudiness and VCSH have been observed and will continue till 23z. Overall winds will be out of the SE at 5-10 kts, with sea breeze variations modifying the direction for TJSJ/TJMZ/TJBQ.
MARINE . Fairly tranquil marine conditions with seas between 1 and 4 feet will prevail across the regional waters through at least Friday afternoon. Marine conditions are expected to deteriorate as a northerly swell invades the Atlantic waters and local waters by Friday evening into the weekend. Therefore, a Small Craft Advisory is in effect for the offshore Atlantic waters by Friday evening. There is a moderate risk of rip currents for beaches along the north coast of Puerto Rico and Culebra. The risk will elevate to high by Friday morning for beaches along the north central coast of Puerto Rico, and by Friday afternoon for the remaining beaches along the north coast of Puerto Rico, including beaches of Mayaguez and Vicinity.
PRELIMINARY POINT TEMPS/POPS. SJU 73 90 74 87 / 20 30 20 50 STT 74 84 74 80 / 30 30 30 30
SJU WATCHES/WARNINGS/ADVISORIES. PR . High Rip Current Risk from Friday evening through Sunday afternoon for Mayaguez and Vicinity-Northeast-Northwest-San Juan and Vicinity-Southeast.
High Rip Current Risk from 6 AM AST Friday through Sunday afternoon for North Central.
VI . None. AM . Small Craft Advisory from 8 PM Friday to 8 PM AST Sunday for Atlantic Waters of Puerto Rico and USVI from 10 NM to 19.5N.
SHORT TERM . LIS LONG TERM . 99 PUBLIC DESK . ICP
Weather Reporting StationsEDIT (on/off)  Help NOTE: Click on distance to see the station location on a map
|Stations||Dist||Age||Wind||Air Temp||Water Temp||Waves||Pressure||DewPt|
|MISP4 - 9759938 - Mona Island, PR||70 mi||51 min||78°F||82°F||1014.3 hPa|
|MGZP4 - 9759394 - Mayaguez, PR||88 mi||57 min||79°F||83°F||1014.1 hPa|
Wind History for Mayaguez, PR(wind in knots) EDIT (on/off)  Help
Airport ReportsEDIT (on/off)  Help Click EDIT to display multiple airports. Follow links for more data.
|Aquadilla, Rafael Hernandez Airport, PR||78 mi||2.3 hrs||SE 5||10.00 mi||Mostly Cloudy||79°F||0°F||%||1013.2 hPa|
Link to 5 minute data for TJBQ
Wind History from JBQ (wind in knots)
|1 day ago||E||Calm||Calm||Calm||S||SW||NW||NW||W||W|
|2 days ago||E||E||SE||E||E||E||E||E||NE||NE||E||NE||E||E||E |
EDIT Weekend mode (on/off) (on/off)  Help One Week of Data
EDIT (on/off)  Help One Week of Data
Weather Map(on/off)  Help Weather Map
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.
Link to Loop
Other links: Northern Pacific Contential US Full GOES-East
Wind Forecast for (21,6,7,8)(on/off)  Help
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