316
FXCA62 TJSJ 071750
AFDSJU
Area Forecast Discussion
National Weather Service San Juan PR
150 PM AST Tue Apr 7 2026
...New SHORT TERM, AVIATION, MARINE, BEACH FORECAST...
.KEY MESSAGES...
Updated at 150 PM AST Tue Apr 7 2026
* A moderate risk of rip currents will prevail tonight across
exposed coastlines.
* Showers are expected across the islands, with activity focusing
over eastern and southeastern areas during the morning and
shifting to the western interior during the afternoon.
* Warmer temperatures will persist through the rest of the week, with
highs reaching the upper 80s to low 90s across coastal and
urban areas.
* Marine and coastal conditions are expected to deteriorate
beginning Friday and continuing through the weekend, becoming
increasingly hazardous.
* For the U.S Virgin Islands, variable weather conditions will
persist during the period.
&&
.Short Term(This evening through Thursday)...
Issued at 150 PM AST Tue Apr 7 2026
During the morning hours, cloudy skies and showers continued
across eastern Puerto Rico, while more tranquil conditions
persisted elsewhere. Based on radar estimates since midnight,
maximum rainfall accumulations of around 2 to 3 inches were
observed between Maunabo and Rio Grande. This rainfall resulted in
some flooding issues: the first in Naguabo, where the Rio Blanco
overflowed its banks, affecting PR-191 and PR-31 near Exit 22,
and the second in Rio Grande, where the Rio Grande overflowed,
impacting Sector Galateo and resulting in road closures. Other
areas, including Guayama, Yabucoa, Las Piedras, and Juncos,
recorded around an inch of rainfall in localized spots. The USVI
experienced some passing showers, but no significant accumulations
have been recorded at this time. Winds have been mainly from the
southeast at around 10 to 15 mph, with some higher gusts. Daytime
maximum temperatures are ranging from the mid 80s to the low 90s
across low-elevation, urban, and coastal areas, and from the upper
70s to the low 80s in the mountainous region. Across the USVI,
temperatures are fluctuating the upper 80s.
As we move into the early afternoon hours, cloudiness has been
increasing across Puerto Rico, accompanied by light showers moving
from the interior into northern areas under a southeasterly flow
driven by surface high pressure over the central to eastern
Atlantic. According to the latest precipitable water (PWAT)
satellite derived imagery and the 12Z TJSJ sounding, an air mass
with values between 1.5 and 1.6 inches is dominating the region,
which is considered near normal for this time of year. Under this
flow pattern, ample moisture will continue to pool over the
region, enhancing showery weather from time to time. Combined with
diurnal heating and local effects, another round of strong
afternoon convection is expected across northwestern
municipalities of Puerto Rico. Consequently, a limited to elevated
risk of flooding persists in that area, with the potential for
ponding of water on roads and in poorly drained areas, as well as
flooding in urban areas, roads, and small streams. Additionally,
thunderstorms remain possible, as 500 mb temperatures are in the
25th percentile, which could further enhance convective activity.
By Wednesday and Thursday, a similar pattern will persist, but
models agree that rainfall coverage and accumulations will be
lower compared to recent days. The 250 mb heights and 500 mb
temperatures are expected to increase, while 700 to 500 mb
relative humidity values will decrease, bringing some added
stability. Even so, with sufficient moisture and prevailing wind
flow, showers will continue to affect windward sectors during the
night and morning hours, followed by afternoon convection across
northwestern Puerto Rico. This will maintain a localized limited
to elevated flood risk across the northwestern quadrant of the
island. Over the USVI, passing showers overnight from time to
time, but overall sunny conditions.
In the short term, warmer-than-normal temperatures will persist,
as reflected in the 925 mb temperature guidance, which remain in
the 75th percentile over the next few days. As a result, a limited
heat risk will continue across low elevation and urban areas of
the islands.
&&
.LONG TERM(Friday through Tuesday)...
Issued at 425 AM AST Tue Apr 7 2026
Conditions will become relatively stable through the long term
period. Expect isolated to scattered showers, mainly during the
afternoon hours due to daytime heating. Activity will be focused
across western and interior Puerto Rico, with minimal impacts
elsewhere. Overall rainfall coverage and intensity should be lower
than previous days. Winds will remain from the east-southeast,
continuing to bring typical pockets of moisture into the region,
from time to time. Model guidance continues to suggests the gradual
return to a wetter and more unstable pattern. An approaching deep-
layered trough combined with above-normal moisture could lead to
increasing shower and thunderstorm activity across the region,
particularly from Monday onwards.
&&
.AVIATION...
(18Z TAFS)
Issued at 150 PM AST Tue Apr 7 2026
VFR conditions will persist along all TAF sites during the
period. Some TSRA to SHRA might result in a brief MVFR condition
due to reduced VIS and lower ceilings, affecting the FL020 to
FL050 from 07/18Z til 07/23Z at TJBQ. VCSH is expected at the
remaining TAF sites. Winds will persist from E-SE up to 3 KM at 15
knots or less, diminishing at 07/23Z, becoming VRB and light.
&&
.MARINE...
Issued at 150 PM AST Tue Apr 7 2026
A broad surface high-pressure system extending from the Central
Atlantic into the Caribbean will mainly bring moderate trades across
the local waters. Some hazardous marine conditions remain across the
offshore Atlantic waters and the Anegada Passage until 6 PM AST.
After that, conditions will briefly improve, with seas mostly up to
6 feet across the offshore Atlantic waters and lower in the coastal
waters. Another weak northeasterly swell is forecast to arrive
across the Atlantic waters, likely resulting in hazardous marine
conditions along the coast. By Friday, model guidance suggests a
significant long-period northerly swell will arrive locally,
resulting in hazardous marine and coastal conditions. Additionally,
on Saturday into Sunday, surface winds will briefly become lighter
and from the east as an induced surface trough moves north of the
local region.
During the period, localized hazardous marine conditions will be
present, mostly near thunderstorms that develop over the local
waters. For more information about the marine forecast, please
visit www.weather.gov/sju/marine.
&&
.BEACH FORECAST...
Issued at 150 PM AST Tue Apr 7 2026
A broad surface high-pressure system extending from the Central
Atlantic into the Caribbean will mainly bring moderate trades
across the local waters. This will result in breaking waves
between 4 and 5 feet along all the coastal areas of Puerto Rico
and the U.S. Virgin Islands. Therefore, there is a moderate risk
of rip currents across all the coastal areas tonight. Conditions
will deteriorate on Wednesday, when energy arrives across the
northern and eastern sections, resulting in breaking waves up to 6
feet along the north and northeast coast. Conditions will
deteriorate further on Friday when a northerly swell arrives,
increasing breaking waves and resulting in life-threatening rip
currents and, in some areas, beach erosion. Residents and visitors
are encouraged to check the latest beach conditions before
heading to the beach at eather.gov/sju and www.weather.gov/beachforecast.
&&
.SJU WATCHES/WARNINGS/ADVISORIES...
PR...None.
VI...None.
AM...Small Craft Advisory until 6 PM AST this evening for AMZ711-723.
&&
$$
SHORT TERM...YZR
LONG TERM...MMC
AVIATION/MARINE/BEACH...LIS
NWS SJU Office Area Forecast Discussion