Scientific Forecaster Discussion
Area forecast discussion
National Weather Service San Juan PR
212 PM AST Friday Feb 27 2015
Synopsis...a surface and middle to upper level ridge will continue to
strengthen across the region and remain in place through Sunday.
These features will help to support fairly strong cap inversion...
windy conditions and significant drying weather pattern through the
Discussion...Doppler weather radar detected only light shower
activity over the Atlantic coastal waters so far this afternoon. Not
not significant precipitation was detected over land areas.
Surface high pressure and a middle to upper level ridge will remain as
the main weather features across the northeast Caribbean for the
next few days. The surface high pressure is expected to maintain a
tight pressure gradient across the region. This will lead to fairly
strong easterly trade winds and mostly fair weather conditions
across the local islands. Therefore the current dry and stable
weather pattern and breezy conditions are in store for the next
couple of days. However...very small patches of low level moisture
embedded in the easterly trades will induce the development of brief
passing showers across eastern sections of Puerto Rico...Vieques...
Culebra and across the U.S. Virgin Islands during the nights and
early morning hours with limited convection...if any...over western
and interior Puerto Rico during the afternoons. An increase in
moisture transportation is expected early next week as an upper
trough amplify across the northeast Caribbean.
Aviation...VFR conditions expected across the local flying area
through the forecast period. Only a few vcsh possible across the USVI
and leeward terminal tonight and early Friday. Latest tjsj sounding
indicated an easterly wind flow up to 40 knots all the way from the
surface to 15k feet
Marine...strong easterly winds will continue overnight and remain
strong up to at least 15k through the forecast period. These winds
will generate rough seas of 6 to 8 feet. Small Craft Advisory will
remain in effect for most of the local waters along with a high risk
of rip currents.
Preliminary point temps/pops...
sju 76 86 75 85 / 20 20 20 10
stt 74 85 74 85 / 20 20 20 10
PR...red flag warning until 4 PM AST this afternoon for south coastal
plains and Mona island.
Vi...red flag warning until 4 PM AST this afternoon for St Croix.
Coastal waters... Small Craft Advisory until midnight AST Sunday night for Anegada
Passage southward to 17n-Atlantic waters of Puerto Rico and
USVI from 10nm to 19.5n-Caribbean waters of Puerto Rico
from 10 nm to 17n-coastal waters of northern USVI and
Culebra out 10 nm-coastal waters of southern USVI Vieques
and eastern Puerto Rico out 10 nm-Mona Passage southward to
Small Craft Advisory until 6 PM AST this evening for coastal
waters of southern Puerto Rico out 10 nm.
Small Craft Advisory until 6 PM AST Saturday for coastal waters
of northern Puerto Rico out 10 nm.