AFDSJU
AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE SAN JUAN PR
230 PM AST MON APR 18 2005
.DISCUSSION...THE MOVEMENT OF THE FRONTAL BOUNDARY LOCATED SOMEWHERE
ALONG THE EASTERN PART OF HISPANIOLA...HAVE MOVE VERY LITTLE AS
DEPICTED BY SCATTEROMETER LAST NIGHT AND EARLY THIS MORNING. IT IS
EXPECTED TO CONTINUE MOVING SLOWLY CLOSER TO THE LOCAL ISLANDS INTO
THE MONA PASSAGE LATER TODAY. ANY WAY...SEEMS THAT THE WEATHER
CONDITIONS FOR TUESDAY...WEDNESDAY AND THROUGH THE WEEK WILL BE
ACTIVE OVER THE LOCAL AREA.
THERE ARE SEVERAL INTERRELATED FEATURES ASSOCIATED TO THIS. THESE
ARE...THE FRONTAL BOUNDARY...ABUNDANT MOISTURE...A STRONG SOUTHWEST
JET AND LOW LEVEL CONFLUENCE OF THE WINDS. ASIDE OF THIS...GFS MODEL
GUIDANCE WHICH HAVE BEEN CONSISTENT PICKING UP THESE FEATURES
SUGGEST GOOD DYNAMICS TOMORROW...WEDNESDAY AND CONTINUING THROUGH
THE END OF THE WORK WEEK.
THE ABOVE INFORMATION SUGGEST THE POSSIBILITY OF PERIODS OF VERY
HEAVY RAINFALL ESPECIALLY OVER PUERTO RICO...THE MONA PASSAGE AND
ATLANTIC COASTAL WATERS. CONSEQUENTLY...I AM ADDING HEAVY
PRECIPITATION IN SOME OF THE GRIDS.
WINDS WILL BE LIGHT AND THE SHOWERS MOVEMENT WILL BE SLOW AND
SOMEWHAT ERRATIC. THIS ADD ANOTHER INGREDIENT TO THE URBAN AND/OR
FLASH FLOODING POTENTIAL.
IN A LONG TERM BASIS...ALTHOUGH ERRORS MAY BE LARGE AT THIS
TIME...GUIDANCE SUGGEST A LOW LEVEL STREAM OF VERY MOIST AIR FROM
THE LOWER LATITUDES OVER THE LOCAL ISLANDS WHICH MAY RESULT IN AN
EVEN WETTER WEATHER PERIOD. HOWEVER...GRIDS FOR THIS PERIOD REMAIN
"CONSERVATIVE" BECAUSE THE UNCERTAINTIES WE CAN HAVE.
&&
.MARINE...VERY HEAVY PRECIPITATION AND THUNDERSTORMS ACTIVITY CAN
RESULT IN HAZARDOUS MARINE CONDITIONS DURING THIS WEEK ESPECIALLY
OVER THE MONA PASSAGE AND ATLANTIC COASTAL WATERS. THIS INCLUDE THE
POSSIBILITY OF WATERSPOUTS DEVELOPMENT DUE TO THE VERY UNSTABLE
LOCAL AIRMASS.
&&
.AVIATION...HEAVY DOWNPOURS WILL RESULT IN LOW VISIBILITIES AND
CEILINGS ESPECIALLY FOR THE SECTORS OF PUERTO RICO.
&&
.CLIMATE...APRIL AND MAY RAINS ARE USUALLY HEAVY AND SEEMS THAT THIS
WILL BE THE CASE THIS WEEK.
Great news for us as we were almost at the time of rationing of water as the lakes were going down.And also if you recall in my thread of the drought many fires caused by espontanious combustion were sparked by the dry spell.But as I said in that other thread what happens in the climate in Puerto Rico has no implications about how the hurricane season will be.What is happening in the first months of 2005 I consider it to be normal although March was a little bit below normal in terms of precipitation.Late April and May are one of the wettests periods in the year here followed by August and then October.




