Area Forecast Discussion
Issued by NWS San Juan, PR
FXCA62 TJSJ 260808
Area Forecast Discussion
National Weather Service San Juan PR
408 AM AST Sun Feb 26 2017
.SYNOPSIS...A surface low pressure system will continue to move
northeastward across the northwest Atlantic today. A strong
surface high pressure will move over the southwestern Atlantic
pushing the associated frontal boundary eastward. This high
pressure will maintain the local winds mostly from the east this
morning and from the east to east-northeast this afternoon and
Monday. As the surface high pressure moves toward the central
Atlantic, patches of low level moisture embedded in the northeast
trades are expected to moves across the region early in the week
increasing the chances of showers.
.DISCUSSION...Under an easterly wind flow, Doppler weather radar
detected isolated showers moving westward across the U.S. Virgin
Islands and eastern sections of Puerto Rico overnight and early
this morning. Not significant precipitation was observed
elsewhere across the region so far this morning. Under a relative
stable weather pattern, only small patches of moisture associated
with the easterly wind flow are expected to affect the eastern and
sections of Puerto Rico during the rest of the morning hours, but
mostly sunny skies are expected across most of the region. The
limited moisture in combination with daytime heating, sea breeze
convergence and other local effect are still expected to produce
some cloudiness and showers across interior and western Puerto
Rico this afternoon.
An increase in wind speed is expected early in the week, as the
surface high pressure strengthens over the central Atlantic just
north of the region. A generally dry and stable weather conditions
are expected to prevail over the region today. By early next
week, areas of moisture embedded in the trades will move across
the region from time to time, increasing the frequency of trade
wind showers across the local islands and surrounding waters.
.AVIATION...VFR conds will prevail across all terminals through the
forecast period. Few passing showers will affect the coastal waters
N and E of PR and en route btw PR and the Northern Leeward islands
til 26/12Z. Sf winds light and variable...bcmg fm E-NE aft 26/14Z...
incr 10-15 kts aft 26/13z with sea breeze variations. L/lvl wnds fm
E-NE 5-15 kts Blo FL100...bcm fm S-SW up to FL250...then fm N and
incr w/ht abv. Mostly SKC abv FL100. No sig operational impacts ovr
local flying area or at local TAF sites attm.
.MARINE...Seas have diminished near 5 feet across the offshore
Atlantic waters. Seas are expected to increase once again Monday
night into Tuesday.
.PRELIMINARY POINT TEMPS/POPS...
SJU 85 74 85 74 / 20 20 20 40
STT 83 73 85 74 / 20 20 20 40