Since 2001 providing the latest information on tropical cyclone activity in the Atlantic Basin and the weather conditions in Puerto Rico.

Local Weather Conditions

 

National Weather Service Today's Weather Impact Levels

National Weather Service Forecast for: San Juan, Puerto Rico  

Updated: 7:15 pm AST Nov 6, 2024

Hazardous Weather Outlook
Rip Current Statement
Flood Advisory
Tonight

Tonight: Showers and possibly a thunderstorm.  Low around 76. East northeast wind 10 to 13 mph.  Chance of precipitation is 80%. New rainfall amounts between 1 and 2 inches possible.
Showers
Lo 76 °F
Thursday

Thursday: Showers and possibly a thunderstorm.  High near 84. Northeast wind 10 to 15 mph becoming light  in the afternoon. Winds could gust as high as 20 mph.  Chance of precipitation is 80%. New rainfall amounts between 2 and 3 inches possible.
Showers
Hi 84 °F
Thursday
Night
Thursday Night: Scattered showers and thunderstorms before 9pm, then scattered showers between 9pm and midnight, then scattered showers and thunderstorms after midnight.  Mostly cloudy, with a low around 77. Calm wind becoming south southeast around 6 mph in the evening.  Chance of precipitation is 50%.
Scattered
Showers
Lo 77 °F
Friday

Friday: Scattered showers and thunderstorms, then showers likely and possibly a thunderstorm after noon.  Mostly cloudy, with a high near 90. South southeast wind 9 to 11 mph.  Chance of precipitation is 70%.
Showers
Likely
Hi 90 °F
Friday
Night
Friday Night: Scattered showers.  Partly cloudy, with a low around 77. Southeast wind 5 to 7 mph.  Chance of precipitation is 30%.
Scattered
Showers
Lo 77 °F
Saturday

Saturday: Showers likely, with thunderstorms also possible after noon.  Partly sunny, with a high near 89. East wind 7 to 11 mph.  Chance of precipitation is 60%.
Showers
Likely
Hi 89 °F
Saturday
Night
Saturday Night: Partly cloudy, with a low around 78. East wind around 7 mph.
Partly Cloudy
Lo 78 °F
Sunday

Sunday: Scattered showers.  Mostly sunny, with a high near 87. East wind 6 to 14 mph.  Chance of precipitation is 50%.
Scattered
Showers
Hi 87 °F
Sunday
Night
Sunday Night: Scattered showers.  Partly cloudy, with a low around 77. East wind 8 to 10 mph.  Chance of precipitation is 30%.
Scattered
Showers
Lo 77 °F

National Weather Service Forecast Details

 

GRLevel3 Radar

  [10/10
GRLevel3 radar from NWS station TJUA

Day 1 rainfall

Day 2 rainfall

Day 3 rainfall

698
FXCA62 TJSJ 062132
AFDSJU

Area Forecast Discussion
National Weather Service San Juan PR
532 PM AST Wed Nov 6 2024

.SYNOPSIS...

Wet and unstable weather conditions are expected to continue into
the next few days. The main feature will be a deepening upper-
level trough and plenty of moisture across the islands. The
National Hurricane Center is monitoring a low within a trough with
a low chance of formation in the next two days that would affect
the local pattern tomorrow into Friday. Hazardous marine and
coastal conditions are in effect with several small craft
advisories and high risk of rip currents in effect through at
least the end of the week. For more information visit
www.weather.gov/sju/marine.

&&

.SHORT TERM...Tonight through Friday...

Rain showers and thunderstorms began developing during the
morning, particularly in the metropolitan area and eastern parts
of Puerto Rico. Throughout the day, persistent bands of showers
moved across the region. Radar estimates indicated rainfall totals
ranging from 1 to 3 inches in the northern and eastern sections of
Puerto Rico, as well as in St. Thomas in the U.S. Virgin Islands.
While temperatures were generally moderated by cloud cover and
showers, they reached the low 90s in the far southwest of Puerto
Rico. In contrast, temperatures in the highest elevations remained
in the lower 70s.

The wet and unstable wet pattern is expect to continue
particularly the rest of tonight into early afternoon hours of
tomorrow Thursday. Through the rest of the afternoon and into the
overnight hours, enhanced shower activity is expected as a new
pulse of moisture, associated with the lingering remnants of a
frontal boundary, approaches the region. Also a trough of low
pressure is also forecast to pass over the area between Thursday
morning and Friday maintaining enough instability. The National
Hurricane Center is monitoring this system due to its low
potential for development over the next 48 hours to 7 days. As a
result, tonight and tomorrow could bring potential impacts across
the forecast area, including urban and small stream flooding,
flash flooding in flood-prone areas, and rapid river rises. With
soils already saturated, there is also an elevated risk of
landslides in steep terrain. The flooding risk is expected to
range from moderate to significant, particularly in the northern
and eastern parts of Puerto Rico. We advise residents and visitors
to closely monitor the forecast for any advisories, or warnings
that may be issued by our local office related to the expected
rain.

&&

.LONG TERM...Saturday trough Wednesday...
./FROM PREV DISCUSSION...Issued at 512 AM AST Mon Nov 6 2024/

The long-term forecast will start wet and unstable. At the upper
levels, a low pressure located over the western Atlantic will
keep instability aloft, due to moisture between 500-700 MB being
above normal by two standard deviations on Saturday and colder
temperatures at 500 MB of minus 7 degrees Celsius. These unstable
conditions, combined with plenty of tropical moisture will be in
place due to the passage of a low pressure. This trough of low
pressure is now being monitored by the National Hurricane Center
and has a low chance of formation in the next two & seven days.
A low pressure is expected to develop and move westward to result
in a east-southeasterly wind flow across the region. The surface
wind will inject the islands with abundant tropical tropical
moisture trapped between the 700 to 300 MB. Given the actual
forecast pattern, the islands can expect widespread shower
activity with the bulk of the showers across northeastern,
interior and northwestern sections of Puerto Rico. The U.S. Virgin
Islands can expect a similar pattern with showers affecting the
islands in the early morning hours.


From Sunday through the rest of the long term, the instability of
the upper-level low moves more into the southwestern Atlantic,
and the islands will remain under the influence of a mid to upper-
level ridge. The mid to upper-level ridge will induce warmer
temperatures at 500 MB and create a more stable atmosphere,
limiting the total development of the most vigorous shower
activity. Some dry intrusion is forecast for Sunday, resulting in
less coverage in the afternoon showers. However, for Monday,
tropical moisture from previous systems and a tropical wave moving
westward will increase the moisture available for the development
of the daily showers. Surface winds will change under the
influence of a strong building surface high pressure from the
western Atlantic extending into the Central Atlantic becoming more
east-northeasterly on Sunday, easterly on Monday, and
southeasterly TUesday and beyond, as the ridge moves eastward
into the north-central Atlantic. This change in the winds will
affect the presence of showers in the same areas of Puerto Rico
during that period.

&&

.AVIATION...
(18Z TAFS)

Mostly VFR conds will prevail, however sporadic showers and
thunderstorms in the NE flow will continue to pop up bringing MVFR
conds and some mtn obscurations. Sfc wind flow is NE 5-12 kt but
by FL005-015 increases to 15-25 kt. These winds are expected to
cont thru 07/14Z then turn to the SE thru 07/21Z. Max winds NNW
57-67 kt btwn FL405-465.

&&

.MARINE...

A surface high pressure across the western to central Atlantic
and the proximity of a trough of low pressure will promote fresh
to locally strong northeasterly winds. In combination with pulses
of northerly swells will result in hazardous seas. Also, increased
thunderstorm activity is expected over the next few days. Small
Craft Advisories are in effect across most of the regional and
local waters and passages through at least Friday.

&&

.BEACH FORECAST...

Tonight, the risk of the rip currents will increase to high,
particularly for beaches along the northern coast of Puerto Rico,
Culebra and the U.S. Virgin Islands, persisting through the end
of the workweek due to the proximity of a trough of low pressure
and some long-period waves reaching the islands. For more details,
please consult the Surf Zone Forecast (SRFSJU).

&&

.SJU WATCHES/WARNINGS/ADVISORIES...
PR...High Rip Current Risk through Friday afternoon for PRZ001-002-
     005-008-012.

     High Rip Current Risk from Thursday morning through Friday
     afternoon for PRZ010.

VI...High Rip Current Risk through late Thursday night for VIZ001.

     High Rip Current Risk from Thursday morning through late
     Thursday night for VIZ002.

AM...Small Craft Advisory until 2 PM AST Friday for AMZ711-712-716-
     741.

     Small Craft Advisory until 6 AM AST Friday for AMZ723-742.

     Small Craft Advisory from midnight tonight to 6 PM AST Thursday
     for AMZ726.

&&

$$

SHORT TERM...YZR/DS
LONG TERM....LIS
AVIATION...WS/DS
PUBLIC...MNG

NWS SJU Office Area Forecast Discussion

Saharan Air Layer

Wind Shear Tendency

Sea Surface Temperatures

Sea Surface Temperatures Anomalies

200hPa Velocity Potential Forecast