Scientific Forecaster Discussion
Area forecast discussion
National Weather Service Miami Florida
342 am EDT Sat may 23 2015
Weak surface trough, this very early morning, left over from weak
low pressure/stationary front over central Florida yesterday, will kick
off a few showers/storms offshore and near the beaches of Palm
Beach/Broward/Miami-Dade counties. As strong surface high
pressure moves off the East Coast today, the pressure gradient
increases into Sunday and the resulting deep easterlies lead to a
high risk of rip currents for the Holiday weekend. A pocket of
drier air aloft compared to yesterday, will be forced into the
East Coast on veering 850 mb and 700 mb wind flow later today. Precipitable waters may
drop off slightly by this evening. NE to east winds will combine with
a late day Gulf Breeze to place most showers/storms across the
West Coast and interior sections. Although 500 mb temperatures warm slightly
and 700 mb-500 mb lapse rates decrease a little compared to yesterday,
can't rule out a few stronger storms West Coast today.
Showers may form along the East Coast tonight and during part of
Sunday morning as the easterlies really get underway. Downright
breezy into Sun afternoon with some 25kt gusts along the East
Coast possible. Some of the morning coastal showers may penetrate
inland. Monday looks similar, but again most storms will be
interior and West Coast.
With the cold 500 mb trough lifting from the northeast Sunday, and a
deep West Coast/Four Corners trough persisting, a middle level ridge
will have free reign to grow and expand not only over Florida, but
eventually over the southeast Continental U.S. Coast. With the ridge cutting
off through h3, large subsidence will lead to a significant amount
of drier midlevel air across the East Coast and Florida by the
middle of next week. Model soundings actually drop precipitable waters close to 1"
at times along the East Coast. Although there will remain
opportunities for storms on the West Coast, probability of precipitation will be rather low
by midweek regionwide.
As the 500 mb ridge and surface high eventually move northeast and
away from the eastern Seaboard, the gradient will relax and
persistent moderate easterlies will begin to weaken a bit into
The gradient increases as surface high pressure moves off the
eastern Seaboard today. Winds become increasingly easterly and
stronger through the weekend, close to 15kts by late today, then
near 20kts sustained late Sunday and Monday, else 15-20 kts through
the rest of the forecast. Middle and upper level high pressure will
remain anchored along the East Coast.
Preliminary point temps/pops...
West Palm Beach 88 78 87 79 / 20 30 30 20
Fort Lauderdale 88 78 87 79 / 20 30 30 30
Miami 89 77 88 78 / 20 20 30 30
Naples 93 73 93 72 / 70 30 60 20
Florida...high rip current risk from this evening through Tuesday
afternoon for flz168-172-173.