Flood Potential Outlook
Issued by NWS San Juan, PR

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FGCA72 TJSJ 010915 CCA

National Weather Service San Juan PR
515 AM AST Thu Mar 1 2018

...The flood risk is near normal across the forecast area...


Current Streamflow...
The 28-day average streamflow from the U.S.Geological Survey
(U.S.G.S.) river gauge network indicates most of the streamflows
across Puerto Rico between the 25th and the 90th percentile which
is near to above the normal range. There are a few outliers across
the southeastern slopes of Puerto Rico running below the 24th
percentile which is below or much below the normal range. There
is no streamflow data for the U.S. Virgin Islands.


Previous Rainfall...
Near to above normal rainfall was observed across the local
islands. Shower activity during the past few months were noted
mainly across the northern and eastern half of Puerto Rico as
well as the outlying islands. Some locally induced showers and
thunderstorms were also observed across the southwest portions
of Puerto Rico.

Rainfall Observations at the primary climate sites

DFN = Departure from Normal
Rainfall (in.)

San Juan Area

       Obs. Value     Normal     DFN

30-day rainfall5.18 2.39 2.79
60-day rainfall10.36 6.15 4.21
90-day rainfall13.69 11.17 2.52

Cyril E. King Airport

                  Obs. Value     Normal     DFN

30-day rainfall 2.641.43 1.21
60-day rainfall 6.01 3.81 2.20
90-day rainfall 7.19 6.77 0.42

Henry E. Rohlsen Airport

                  Obs. Value     Normal     DFN

30-day rainfall1.98 1.65 0.33
60-day rainfall2.37 3.79 -1.42
90-day rainfall6.83 6.76 0.07


The fire season has so far been relatively normal for this time
of the year. Climatologically, the southern slopes of Puerto Rico
and Saint Croix experience the warmest temperatures and the
driest soils during this season. The most significant fire
weather threat is expected to continue for preferred areas along
the south coast of PR...particularly Guanica...Cabo Rojo and around
Camp Santiago.


Based on data from the Water Authority and the U.S.G.S. the major
water supply reservoirs across Puerto Rico are in optimum
conditions. However, the Guajataca Dam is well below the normal
pool because the U.S. Army Corps continues to repair the spillway
which was affected by excessive runoff during Hurricane Maria.


Station             Normal Pool Elev.       Latest Observation

Lago Guajataca      646                     625.33
Lago Dos Bocas      295                     294.95
Lago La Plata       155                     167.97
Lago Carraizo       132                     133.16
Lago Cidra          1322                    1322.31


Future Rainfall...
Climatologically, the dry season continues across the local islands
through March with a transition during April and the onset of the
wet season on May. Based on the CariCOF outlook there is equal chance
to observe below, near or above normal rainfall during the next few months.


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