Scientific Forecaster Discussion
fxus62 kmlb 210104
Area forecast discussion
National Weather Service Melbourne Florida
904 PM EDT Wed Sep 20 2017
Tonight-Thu...light onshore flow will become near calm inland. This
flow will increase on Thu as the pressure gradient tightens a bit as
major Hurricane Marie begins to lift further northward. Small threat
of precipitation will be along the Treasure Coast overnight and
southward from Melbourne on Thu where higher moisture values will be
located. An old frontal boundary across the south will provide a
focus for convective development in these locations. Thunder chances
along the coast Thu would probably be during the morning to early
afternoon, then shifting inland.
Aviation...mostly VFR conditions should continue. Greatest threat
to see MVFR conditions from a passing shower will be south from
kvrb. Terminals south from kmlb will have a schc to chance threat for
shower activity on Thu with perhaps an isolated thunderstorms and rain. Onshore surface
winds will continue.
Marine...overnight-Thu...the weak onshore winds at or below 10 kts
overnight will increase through the day Thu to 10-15 kts over the
open Atlc. This as the pressure gradient begins to tighten a bit
ahead of the approach of major Hurricane Maria. Seas will continue
to be slow to subside overnight due to lingering swells from Jose,
so exercise caution statements will still linger over the Gulf
Stream. Seas continue to subside slowly Thu.
Hydrology...previous...moderate flooding along the Saint Johns
River near Cocoa, Sanford, Deland and Astor is forecast to change
little through late week. The Saint Johns River above Lake Harney
near Geneva is forecast to remain in major flood stage.