Marine Weather and Tides
9/17/2018 XTide broke when 1and1 "upgraded" my server. It has been esculated. I am sorry for the problem.
|Sunrise 6:11AM||Sunset 6:21PM||Friday September 21, 2018 11:22 AM AST (15:22 UTC)||Moonrise 4:22PM||Moonset 3:12AM||Illumination 89%|
7 Day Forecast for Marine Location Near Lomas, PRHourly EDIT Help
Area Discussion for - San Juan, PR  (on/off)  Help NOTE: mouseover dotted underlined text for definition
|Fxca62 tjsj 211457|
area forecast discussion
national weather service san juan pr
1057 am ast Fri sep 21 2018
Update Mostly fair weather skies and hazy conditions expected
to continued across most of the region into the evening hours.
A few locally and diurnally induced afternoon showers will remain
possible over parts of central and west to southwest pr. Activity
will quickly diminish around sunset. Recent tjsj 21 12z upper air
sounding was considerably drier today with pwat values down to 1.24
inches, suggesting an overall dry and stable sal airmass. Aerosol
products and recent satellite imagery both suggest that the suspended
saharan dust particulates spread across the region is to gradually
diminish during the rest of the day and overnight. Any shower activity
across the islands should diminish around sunset leaving partly cloudy
to mostly clear skies. Limited passing showers expected across the
coastal waters and windward side of the islands during the overnight
and early morning hours. No changes made to the inherited forecast
package and reasoning at this time.
Aviation update Vfr durg entire prd. No chg to previous avn
discussion. Suspended dust particulates mainly btw fl050-fl150
across local flying area with hz alqds... But no restrictions
to flt vis. Sfc vsby 5-6sm some local terminals. Few clds nr
fl030... Fl050. Sfc wnds e-ne 10-15 kts with ocnl hir gusts and
local sea breeze variations.
Marine update Winds 10-15 kts and seas 3-5 feet will continue
through Saturday. A northerly swell still forecast to move into
the outer atlantic waters by Saturday night, then spread across
the rest of the atlantic waters and local passages over the rest
of the weekend into early next week.
Prev discussion issued 515 am ast Fri sep 21 2018
synopsis... A generally fair and stable weather pattern with hazy
skies is expected to prevail today. As the ridge pattern aloft
weakens, the chance for showers and thunderstorms will increase
early next week.
Short term... Today through Sunday...
recent satellite imagery shows a patch of low level moisture just
east of the leeward islands. This moisture will continue to move
to the west and could cause showers across the u.S virgin islands
and eastern areas of puerto rico this morning. Dry saharan air
mass will continue to prevail over the region and cause hazy milky
skies today. Analysis of the recent skew-t shows a plethora of
dry air from 700 to 500 mb today, this will limit the development
of showers and thunderstorms today across the area. If showers do
develop today they will be short-lived as a result of limited
moisture and subsidence provided by the high pressures systems.
This drier at the mid to upper levels of the atmosphere is
forecast to remain through late Sunday. Rh values at 500 to 250 mb
will range from 20 to 40 percent, but from 1000 to 850 mb rh
values will range from 60 to 80 percent starting on Saturday. An
increase in low level moisture is forecast on Saturday as moisture
moves in from the eastern caribbean and north atlantic as a upper|
level trough deepens to the northeast of the leeward islands.
This combined with diurnal heat could cause scattered showers
across the area through Sunday.
Otherwise, pleasant warm weather is expected with temperatures in
the upper 80s to lower 90s with easterly winds of 10 to 15 mph with
higher gusts possible.
Long term... Monday through Sunday
a weak mid level ridge will hold much of the week, eroding by the
end of the cycle as a mid to upper level trough establishes west of
the forecast area. At lower levels, easterly winds will prevail
through the end of the week with an induced surface trough moving
across the eastern caribbean sat-sun. Although trade winds will
continue to bring patches of moisture at times, the best moisture
advection - near or exceeding precipitable water values of 2
inches - is anticipate tue-wed as well as sat-sun.
Based on NHC guidance, there is a small but concentrated area of
showers and thunderstorms which is located 650 miles east of the
windward islands with 10 percent of formation chance through 5
Under the aforementioned pattern, expect seasonal weather early
the next week with the chance for organized convection increasing
tue-wed. A wetter and unsettled weather pattern is then on tap
Aviation...VFR conds fcst to prevail through 22 00z across all
terminal sites. Hz skies due to the saharan dust will also continue
today across all of puerto rico. These conds could cause reduced
vsby's through 22 00z. Sfc winds will be out of the east to
northeast at 10 to 15 kts with higher gusts possible.
Marine... Seas 4 to 6 feet across the caribbean offshore waters
as well as the mona passage. Elsewhere, 5 feet or less are expected.
A moderate to locally fresh easterly wind flow will prevail
across the local waters today, becoming gentle to moderate during
the upcoming weekend. The chance for showers and thunderstorms
across the local waters is expected to increase early next week. A
northerly swell will move into the northern outer atlantic waters
Preliminary point temps pops
Sju 90 79 89 78 40 40 40 40
stt 90 80 90 79 40 40 40 20
Sju watches warnings advisories
Short term... Ram
long term... .Ram
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|
|41053 - San Juan, PR||16 mi||53 min||E 14 G 18||84°F||1015.6 hPa|
|SJNP4 - 9755371 - San Juan, PR||16 mi||41 min||84°F||84°F||1016.2 hPa|
|YABP4 - 9754228 - Yabucoa Harbor, PR||16 mi||35 min||89°F||74°F|
|41056||25 mi||53 min||NE 12 G 14||84°F||1015.1 hPa|
|JOXP4 - Jobos Bay Reserve, Puerto Rico||27 mi||98 min||ENE 5.1||88°F||1016 hPa||73°F|
|ESPP4 - 9752695 - Esperanza, PR||28 mi||41 min||87°F||84°F||1015.4 hPa|
|CLBP4 - 9752235 - Culebra, PR||33 mi||41 min||87°F||85°F||1015.9 hPa|
|42085 - Southeast of Ponce, PR||43 mi||83 min||E 14 G 18||89°F||85°F||1014.5 hPa (+0.8)|
|AROP4 - 9757809 - Arecibo, PR||43 mi||65 min||ENE 7 G 12|
Wind History for Fajardo, PR(wind in knots) EDIT (on/off)  Help
Airport ReportsEDIT (on/off)  Help Click EDIT to display multiple airports
|San Juan, Luis Munoz Marin International Airport, PR||11 mi||87 min||ENE 12 G 18||6.00 mi||Partly Cloudy with Haze||86°F||73°F||67%||1016 hPa|
Wind History from JSJ (wind in knots)
|1 day ago||E|
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