190 
fxca62 tjsj 061043 
afdsju 


Area forecast discussion 
National Weather Service San Juan PR 
643 am AST sun Jul 6 2008 


Synopsis...surface high pressure centered across the 
northeastern Atlantic extends southwestward to the eastern 
Seaboard of the United States. This system is expected to prevail 
near stationary for the next few days...creating moderate to 
fresh trade wind flow over the forecast area. 


At middle levels...high pressure located across the central Atlantic will 
dominate the local area for the next few days. Then...this 
feature is expected to move to the west...but as a frontal 
boundary exits the eastern part of the United States...it will 
move back to the central Atlantic by middle week. 


At upper levels...upper trough extends from the central Atlantic 
southwestward to the north of the local area. This system is 
expected to slowly push east northeast for the next few 
days...while a high builds across the northern Leeward Islands by 
middle week. 






&& 


Discussion...isolated to scattered showers have been affecting 
the eastern and northeastern sections of Puerto Rico since 
midnight. However...the rainfall amounts estimated by weather 
Doppler radar ranged from a trace to three quarter of an inch over 
the affected places the past three hours. 


Showers this morning will continue to affect the eastern coasts of 
Puerto Rico as well as parts of the local islands and coastal 
waters as low level moisture pushes westward and across the local 
islands through late this afternoon...before a relatively dry air 
and stable atmosphere conditions move to our area this evening. 
However...patchy low level moisture once again returns by Monday 
morning...increasing the chances for variably cloudy skies with 
scattered showers and even a thunderstorm to affect the eastern 
coasts of Puerto Rico and parts of the local islands between dawn 
and late Monday morning. Then...this moisture will move to the 
west half of Puerto Rico by noon...and in combination with local 
island effects and daytime heating...you will have as a result... 
scattered to localized heavy shower and isolated thunderstorm 
activity mainly across the northwest portion of the island. This activity 
may result in some minor flooding across 
roadways...underpasses...poor drainage and low lying areas as well 
as urban localities. 


Looking ahead for the upcoming week...between late Tuesday and 
Wednesday...Tropical Storm Bertha should be passing well north of 
the island. However...we are keeping close attention to this 
system as it continues evolving across the tropical Atlantic. We will 
maintain adjusting the weather grids as many times we think is 
necessary to keep the public inform at all times with the latest 
data available. 


As of 5 am AST Sunday...the center of Tropical Storm Bertha was 
located near latitude 17.3 north...longitude 43.2 west or about 1310 
miles...2110 km...east of the northern Leeward Islands. 


Bertha is moving toward the west near 22 miles per hour...35 km/hr. A general 
west-northwestward motion with a gradual decrease in forward speed 
is expected during the next couple of days...as Bertha remains over 
the waters of the central tropical Atlantic. It is much too early 
to determine if Bertha will eventually affect any land areas. 


Maximum sustained winds are near 50 miles per hour...85 km/hr...with higher 
gusts. Gradual strengthening is forecast during the next couple of 
days. 






&& 


Aviation...VFR conditions are expected to prevail across the 
local taf sites for most of the time for the next 24 hours. 


&& 


Preliminary point temps/pops... 
sju 88 78 88 78 / 50 10 30 20 
stt 86 78 86 78 / 40 20 30 20 


&& 


Sju watches/warnings/advisories... 
PR...none. 
Vi...none. 
&& 


$$ 


10/17/