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 5:23AM||Sunset 6:08PM||Saturday July 11, 2020 11:24 AM CST (17:24 UTC)||Moonrise 11:30PM||Moonset 11:17AM||Illumination 63%|
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 111543 AFDSJU
Area Forecast Discussion National Weather Service San Juan PR 1143 AM AST Sat Jul 11 2020
UPDATE. Drier air ahead of the tropical wave is over the local islands, causing little to no shower activity. For that reason, the short term forecast was adjusted slightly as the probability of rain is not quite as much as was expected. Otherwise everything still remains unchanged. The tropical wave is now approaching the Leeward Islands and is expected to be in the local area by tonight, causing an increase in shower and thunderstorm activity through Sunday.
AVIATION. VFR conds expected through the forecast period. SHRA/TSRA is expected near TJBQ after 11/17Z. East winds at around 15KT with occasional gusts and sea breeze variations today. An approaching tropical wave will cause an increase in shower activity, then VCSH/VCTS can be expected overnight across the local terminals.
MARINE. Small craft should exercise caution as seas will be up to 6 feet and winds up to 20 knots today. Then seas will begin to deteriorate tonight across the offshore Atlantic waters, with wave heights to 7 feet. Small craft advisory will go into effect tonight for the offshore Atlantic waters. There is a high risk of rip currents for Cramer Park in St Croix today, but a moderate risk for most of the beaches in PR.
PREV DISCUSSION. /issued 520 AM AST Sat Jul 11 2020/
SYNOPSIS . A tropical wave will move across the region later tonight through Sunday. This will increase the potential for urban and small stream flooding across the islands. Increasing winds with the wave will cause choppy seas across portions of the local waters. Drier air and Saharan dust will return early in the week. A TUTT induced perturbation is forecast to increase shower activity by the end of the workweek.
SHORT TERM . Today through Monday .
Showers are forecast to continue to develop over the local waters and eastern Puerto Rico this morning. Later this afternoon, showers and isolated thunderstorms will develop over portions of the interior and western Puerto Rico.
A once healthy tropical wave currently east of the Windward Islands has succumbed to a drier air mass head of it. However, the wave will still increase rain chances across the region late tonight through Sunday evening. Winds will turn to the southeast as the wave approaches the area this evening.
The GFS has precipitable water peaking to 2.2 inches on Sunday, due to the tropical wave. The GFS model has consistently shown the best low-level convergence and upper-level divergence on Sunday morning and late Sunday afternoon. The GFS splits the tropical wave axis in half and brings the northern portion of the wave over eastern Puerto Rico and the U.S. Virgin Islands Sunday morning, and pushes the energy through western Puerto Rico by Sunday afternoon. The southern portion of the wave is forecast to lift from the Caribbean waters and pool over the U.S. Virgin Islands and Puerto Rico by mid-day on Sunday. The wave and its associated moisture should clear the region by Monday morning, with a drier air mass filtering into the area behind the wave. The lingering moisture will combine with local and diurnal effects to induce afternoon showers on Monday.
LONG TERM . Tuesday through Saturday .
Drier air with suspended Saharan dust will return next early next week and linger through Wednesday. A northeast wind flow will prevail as a broad surface high pressure holds across the central Atlantic. However, shallow moisture will move at times with the trade winds to cause passing light showers across the USVI and eastern sections of PR during the overnight and early morning hours. Followed by diurnal afternoon convection over west/southwest PR. Moisture increases during the second half of the week as a retrogressing TUTT and an induced low-level perturbation enters the eastern Caribbean and moves across the region. Therefore, shower and thunderstorm activity is expected to increase, mainly in diurnal activity over central and western PR.
AVIATION . Mainly VFR conditions are expected to prevail across all terminals until 11/15Z. Then SHRA/VCTS are expected to develop across TJBQ and TJMZ until 12/03Z. SHRA/VCTS will develop across PR and the leeward/windward island terminals by 11/22z. SHRA/TSRA could cause brief MVRF conds over the above terminal sites today. Winds will be from the east at 15 to 20 kts with higher gusts and sea breeze variations after 14z.
MARINE . Choppy seas due to increasing winds will continue through the weekend. A tropical wave will deteriorate the marine and weather conditions overnight into Sunday. A moderate risk of rip currents is expected across most of the beaches of PR. There is a high risk of rip currents for the east facing beaches of St. Croix.
PRELIMINARY POINT TEMPS/POPS. SJU 90 78 90 79 / 40 50 50 30 STT 91 80 89 82 / 40 40 30 30
SJU WATCHES/WARNINGS/ADVISORIES. PR . None. VI . High Rip Current Risk through late tonight for St Croix.
AM . Small Craft Advisory from 6 AM to 8 PM AST Sunday for Anegada Passage Southward to 17N.
Small Craft Advisory from 8 PM this evening to 8 PM AST Sunday for Atlantic Waters of Puerto Rico and USVI from 10 NM to 19.5N.
SHORT TERM . JA LONG TERM . 99 PUBLIC DESK . FRG
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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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Wind Forecast for (13,3,4,5)(on/off)  Help
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