Atlantic Hurricane Season 2025 Storm Names

078
FXCA62 TJSJ 071748
AFDSJU

Area Forecast Discussion
National Weather Service San Juan PR
148 PM AST Wed May 7 2025

.KEY MESSAGES...

* Despite the expected drier and more stable conditions over the
  next few days, afternoon showers and isolated thunderstorms
  remain likely and could still lead to localized flooding
  impacts.

* Strengthening winds over the weekend into early next week will
  elevate the risk of life-threatening rip currents for beachgoers
  and create rough seas for small craft.


&&

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

Radar and satellite analysis showed fair conditions across the
region this morning and early this afternoon. Temperatures have
reached the mid to upper 80s, accompanied by light and variable
winds, primarily influenced by the sea breeze. With drier air and
more stable conditions moving in, the forecast has been adjusted.
While flooding is still possible with any significant rainfall,
impacts will be more localized.

As the upper-level trough shifts eastward, a drier and more stable
air mass will begin to move over the region. This will lead to a
decrease in atmospheric moisture, with precipitable water values
dropping to around 1.3 to 1.4 inches on Thursday, below normal for
this time of year, before gradually increasing to about 1.7 to
1.8 inches by Friday night. At the same time, mid-level warming
and drier air above the 700 mb level will limit the potential for
storm development.

Despite the lack of a strong trade wind inversion, overall
instability will be low. However, afternoon showers and isolated
thunderstorms will still be supported by lingering moisture, along
with daytime heating and local effects. These will likely be
isolated, brief, and relatively weak, but any heavier downpours
could still lead to localized flooding, especially in areas with
saturated soils.

Temperatures on Thursday are expected to be near or slightly below
average, providing a brief reprieve from the usual May heat. By
the end of the week, temperatures will likely return to near- or slightly
above-normal levels. Winds will remain light, generally under 15
mph, with calm to light and variable conditions overnight.

.LONG TERM...Saturday through Wednesday...

From previous discussion...issued at 457 AM AST Wed May 7 2025

A mid-level high-pressure system will build over the islands on
Saturday, leading to dry air and subsidence aloft. This will limit
the potential for widespread rain each day. However, the
available low-level tropical moisture, combined with easterly
winds, will still result in periods of showers across the windward
areas in the US Virgin Islands and Puerto Rico. This activity
affecting the windward sections could be enhanced by low-level
convergence. The sea breeze, local effects, and daily heating will
drive the afternoon convection over the interior and western
Puerto Rico.

Winds will pick up over the weekend as a surface high-pressure
builds across the Central Atlantic, tightening the local pressure
gradient. This change in weather patterns will increase the
typical passing showers in the windward areas, which could extend
further inland across Puerto Rico and the US Virgin Islands due to
the increasing winds.


&&

.AVIATION...

(18z TAFs)

Mostly VFR conds for all terminals. However, afternoon convc will
bring -RA/+RA with VCTS at JPS and JBQ after 07/18z, reducing CIGs
and VIS, and likely brief MVFR conds. NE winds btw 9-12 kt, becoming
light and VRB after 07/23z. Winds from the E-NE will increase once
again by 08/13-08/14z btw 10 - 13 kt.


&&

.MARINE...

A broad surface high pressure extending into the Central Atlantic,
in combination with an induced surface trough northeast of the
region, will result in light to gentle through the end of the
workweek. Winds will increase by the end of the weekend as the
surface high pressure builds across the Atlantic. Mariners can
expect seas between 2 to 4 feet, occasionally 5 feet, for the next
several days. Occasional thunderstorms are likely across the regional
waters, especially in the afternoon, resulting in dangerous
conditions for mariners.


&&

.BEACH FORECAST...

Beachgoers can expect a low risk of rip currents at local beaches
throughout the workweek. However, life-threatening rip currents
often occur near groins, jetties, reefs, and piers. The risk of
rip currents will increase to moderate from Saturday onward.


&&

.SJU WATCHES/WARNINGS/ADVISORIES...
PR...None.
VI...None.
AM...None.
&&

$$

DAY SHIFT CREW...ICP/MNG

NWS SJU Office Area Forecast Discussion