Area Forecast Discussion
Issued by NWS San Juan, PR
FXCA62 TJSJ 260955
Area Forecast Discussion
National Weather Service San Juan PR
555 AM AST THU MAY 26 2016
At upper levels, a mid to upper level ridge will continue over the
Eastern Caribbean. While a trough, and it associated Low near
Bahamas, continues anchored over the Western Caribbean. At low
levels, a surface high pressure over the Central Atlantic will
weakens. An induced surface low, off to the north of Hispanola,
will move toward the Florida Peninsula.
Mostly cloudy skies prevailed over during the overnight hours...as
mid to upper level clouds moved over the region. The Doppler
radar detected showers moving across the local waters and some of
them moved inland but no significant amounts were measured.
Satellite imagery showed plenty of clouds across the region or
moving toward the local islands, as a result partly to mostly
cloudy skies are expected this morning. Although little to no
shower activity is expected...some brief passing showers still
possible across the eastern sections of Puerto Rico and the U.S.
Virgin Islands this morning. Then during the afternoon, locally
and diurnally induced convection is likely mainly across portions
of the west interior sections of Puerto Rico. Elsewhere, expect
little to no shower activity. A similar pattern is expected on
Both the GFS and the ECMWF guidances are suggesting the erosion of
the upper level ridge...as a deep layer trough amplifies over Cuba
and Bahamas during the next few days. This pattern will promote
the transport of tropical moisture across the Caribbean region. If
this pattern hold, the potential for shower and thunderstorm
activity should increase across the local region during the
weekend and the upcoming week.
.AVIATION...VFR conds expected to prevail at all TAF sites during
the forecast period, with thin but incrg high/mid clouds moving
across the from the SW. SHRA/TSRA development expected across W PR
aft 26/17z and will cause mtn obscurations and areas of MVFR conds
in and around TJMZ through 26/22z. Winds increasing to 10 to 15
knots from the east after 26/12Z. Winds alf bcmg SW arnd FL170 and
incrg to W 60 kt by FL460.
.MARINE...Winds and seas will continue to slowly subside across
the region as the surface High pressure over the Central Atlantic
weakens. Therefore...expect moderate winds and seas of 3-5 ft over
the region. However...if the model guidance are correct...mariners
should expect an increase in shower and thunderstorm activity
across the local waters by the weekend and into the upcoming week.
.PRELIMINARY POINT TEMPS/POPS...
SJU 88 79 90 76 / 20 40 40 30
STT 89 79 87 78 / 20 40 40 40