National Weather Service San Juan PR
428 AM AST Mon Jan 9 2023
.SYNOPSIS...Passing showers will continue today across the local
islands. A surface high pressure will continue to promote east to
east-southeast winds between 10 to 15 mph. For the afternoon
hours, expect shower activity across the central interior and
western Puerto Rico. This pattern will persist for the next
several days.
&&
.SHORT TERM...Today through Wednesday...
Showers embedded in the winds will continue to reach the region,
especially the windward coastal sections in Puerto Rico and the U.S.
Virgin Islands.
Moisture content has eroded overnight, but GOES-East-derived Total
Precipitable Water imagery still indicates near to above-normal
moisture across Puerto Rico and the U.S. Virgin Islands. In
addition, although instability has diminished, model guidance shows
relatively steep lapse rates at low and mid-levels. A surface high
pressure across the Atlantic Ocean will continue to promote east to
east-southeast winds, enhancing low-level convergence across the
eastern third of PR and pushing showers over the USVI throughout the
morning hours. Showers will spread across the interior and western
sections late in the morning into the afternoon. A similar weather
pattern will continue on Tuesday and Wednesday. However, the
proximity of the remnants of an old cold front may induce a pre-
frontal trough near the islands by Tuesday, pooling additional
moisture across the region. Therefore, we could observe more
frequent showers.
.LONG TERM...Thursday through Tuesday...
A surface high pressure moving off the eastern coast of Florida,
will promote northeasterly winds for the first half of the long-term
period. This pattern will continue to support the development of
passing showers across the US Virgin Islands and the eastern
portions of Puerto Rico. Afternoon convection will be also observed
across the central interior and western Puerto Rico each afternoon
until the end of the workweek. Transitioning into the weekend,
unstable conditions are forecasted as a surface low and a frontal
system move over the Western Atlantic. The surface low is expected
to support more shower development across the region. This system
will set up a pattern that will be similar to the rains from the
previous days. Ponding of water in roads an low drainage areas are
possible with the heaviest rains. Latest model guidance suggest
that a stronger surface high pressure will build over the Atlantic
into the northeastern Caribbean by Monday into Tuesday. This will
promote moderate to fresh northeasterly winds, and bring the
remnants of the front across the local area. Precipitable water
content (PWAT) between 1.60-1.73 inches suggest a moist pattern
that will persist the entire weekend and into early next week.
&&
.AVIATION...
VFR conditions will persist through the forecast period, but
-SHRA/SHRA will reach the coastal areas and may sometimes move over
JSJ/IST/ISX. +SHRA/SHRA will develop across the interior and W-PR
between 09/15-22z, producing mountain obscuration, and SHRA may
affect JBQ too. Winds will continue calm to light and VRB through
09/13z, then increasing to around 15 kt with higher gusts in/near
SHRA.
&&
.MARINE...Seas between 4 to 6 feet are expected today across the
offshore Atlantic waters and up to 3 to 5 feet across the rest of
the coastal waters. Light to moderate winds between 10 to 15 kts
will prevail. Seas are expected to continue improving early this
week. There is a moderate risk of rip currents for most beaches
of the islands with exposure to the northeast.
&&
.SJU WATCHES/WARNINGS/ADVISORIES...
PR...None.
VI...None.
AM...None.
&&
$$
SHORT TERM...CAM
LONG TERM....GRS
AVIATION...CAM