Marine Weather and Tides
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9/4/2019 Fixed the weather maps due to NOAA moving them.
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|Sunrise 5:31AM||Sunset 5:52PM||Wednesday April 8, 2020 12:00 PM CST (18:00 UTC)||Moonrise 6:29PM||Moonset 6:46AM||Illumination 99%|
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 081518 AFDSJU
Area Forecast Discussion National Weather Service San Juan PR 1118 AM AST Wed Apr 8 2020
Widespread showers have continued this morning, with significant rainfall observed in the metro area having caused local flooding. This is associated with moisture convergence over the region due to the remnants of a frontal boundary traversing the area. The SJU 12Z upper air sounding observed precipitable water levels to be at 1.92 inches. The showers have subsided over the island for now during the last couple of hours. However, a resurgence in shower activity is expected this afternoon; sufficient moisture persists to help aid in the development of showers due to local and diurnal effects. The peak in shower activity is expected to be interior Puerto Rico, stretching to northern Puerto Rico, and there is a moderate risk of flooding from these showers.
BKN/OVC skies with CIGS at around FL060 expected across most of the local terminals today. SHRA over the local area will cause VCSH across most of the local terminals with TEMPO MVFR possible as the SHRA affects the terminals. TJSJ, TJMZ, and TJBQ could observe TEMPO MVFR conds this afternoon, while TIST can observe MVFR conds late this afternoon in the the evening. Winds from the SE to NE at 10-15 knots through 08/23Z, becoming lighter thereafter.
Gentle to moderate winds continue out of the east, veering more southeasterly during the day today. Showers also continue, especially across the Atlantic waters and local passages. Seas are gradually subsiding; wave heights up to 6 feet are possible in the Mona Passage, but elsewhere, seas are expected to remain around 5 feet or less. Furthermore, there remains a high risk of rip currents at beaches along the northwest to northeast coasts of Puerto Rico as well as Culebra.
PREV DISCUSSION. /issued 453 AM AST Wed Apr 8 2020/
SYNOPSIS . Moisture associated with a weak frontal boundary continue across the area. This will result in passing showers across the area in the morning hours specially across northern and eastern sections of Puerto Rico. Them in the afternoon hours, scattered to numerous showers will affect the interior and northwestern sections of Puerto Rico. Urban and small stream flooding still possibles with the heaviest showers. Drier weather is anticipated for Friday and continue for the rest of the weekend. Across the regional waters, seas up to 6 feet across the Atlantic waters, therefore small craft operators should exercise caution.
SHORT TERM . Today through Friday .
Abundant low-level moisture associated with an old frontal boundary continues situated over the area. This has resulted in scattered to numerous showers across the northern and eastern portions of Puerto Rico during the overnight hours. Showers will continue to affect these areas through the morning hours. Then, during the afternoon hours, as the available moisture combines with diurnal heating and sea breeze convergence, scattered to numerous showers are expected across portions of interior, western, and the northern half of Puerto Rico. Once again, the low-level flow remains very light and thus, slow-moving showers are expected. Therefore, the potential is there for urban and small stream flooding to materialize in areas in areas that a prolonged period of heavy rainfall activity. Across the USVI, scattered showers are expected from time to time, especially across Saint Thomas and Saint John. The activity across these areas may result in ponding of water on roadways and in poor-drainage areas.
Weather conditions are expected to improve for both Thursday and Friday as the old frontal boundary and its associated moisture lifts to the northeast and drier air moves over the area under a southerly flow. Therefore, more limited shower activity is expected. However, some afternoon showers are still expected to develop across interior and northern portions of Puerto Rico due to local and diurnal effects. Due to the southerly flow, high temperatures along the urbanized areas of northern Puerto Rico may top out in the lower 90s both days
LONG TERM . Saturday through Thursday .
On Saturday, a drier mas mass is expected to move across the region limiting the afternoon convection. However, some passing showers could develop across across western and interior sectors of Puerto Rico. These southeasterly wind flow is expected to result in warmer temperatures across the coastal areas of northern Puerto Rico. On Monday, the wind flow change from east to northeast pushing fragments of low-level moisture across the region. . Afternoon development should be focused over the interior and western sections of Puerto Rico.
On Tuesday to Wednesday, a building high pressure located in the northeastern Atlantic will carry some low-level moisture across the region. This moisture in combination with the local effects can result in more shower activity across the main island, especially in the afternoon hours due to the diurnal heating. For the U.S. Virgin Islands, some passing showers still possible in the morning hours. For Thursday, GFS model guidance suggest a little less moisture across the region, that said, less chance of shower activity could be possible.
AVIATION . Sct SHRA expected across eastern PR and the northern USVI through at least 08/14z, resulting in VCSH mainly across TJSJ/TIST. SHRA expected across interior and northern PR as well as across the northern USVI from 07/16z through 08/23Z. This will result in VCSH across TJMZ/TJBQ/TJSJ/TIST. MVFR conditions will be possible if SHRA affect the terminal sites. Winds will be from the E- ENE below 10 kts through 08/12z, increasing to 12 to 18 kts with sea breeze variations after 08/14z.
MARINE . Across the regional waters, seas between 4 to 6 feet across the Atlantic waters. Therefore, small craft operators should exercise caution especially over the Atlantic waters and Mona passage. Over the Caribbean waters, seas between 2 to 5 feet are expected. A slowly weakening frontal boundary will aid in maintaining showers mainly across portions of the nearshore Atlantic waters and local passages.
expected to continue for the next few days with winds up to 10 knots or less. There is a moderate risk of rip currents at north- facing beaches, with generally low risk elsewhere.
PRELIMINARY POINT TEMPS/POPS. SJU 85 76 90 76 / 50 50 40 20 STT 86 76 84 77 / 50 40 20 10
SJU WATCHES/WARNINGS/ADVISORIES. PR . High Rip Current Risk until 6 PM AST this evening for Culebra- North Central-Northeast-Northwest-San Juan and Vicinity- Southeast.
VI . None. AM . None.
SHORT TERM . JA LONG TERM . CRS PUBLIC DESK . ICP
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