Area Forecast Discussion
Issued by NWS Miami, FL
FXUS62 KMFL 240746
Area Forecast Discussion
National Weather Service Miami FL
346 AM EDT SUN JUL 24 2016
High pressure across the southeast United States and a
south/southeast flow will prevail over South Florida over the next
several days. Aloft, an upper-level low will track across the region
Sunday, with upper-level ridging returning for next week. A tropical
wave will continue moving westward towards the Yucatan, while
another tropical wave moves across the central Atlantic.
NEAR TERM /THROUGH 6PM SUNDAY EVENING/...
Scattered to numerous thunderstorms expected across much of South
Florida today, some potentially strong...
As of 345 AM EDT...A cluster of showers and thunderstorms
continues to be ongoing over the Gulf waters and coastal Collier
County early this morning, as a weak upper-level low is situated
in the eastern Gulf of Mexico. These thunderstorms have exhibited
frequent lightning and heavy rain, with radar estimates indicating
up to 3 inches in spots. The upper-level low will slowly drift
southeast into South Florida during the day today, bringing with
it cooler 500 hPa temps around -8 C, below normal for late July,
later this morning into the afternoon hours.
With the upper low nearby, along with sea breeze/outflow boundary
convergence, expect another active day of showers and
thunderstorms especially this afternoon and evening. Model
guidance is suggesting that the greatest coverage will be across
the interior north into the Lake Okeechobee region, extending east
into inland Palm Beach and Broward counties, with more scattered
activity during the late morning/early afternoon hours along the
Atlantic and Gulf sea breezes. Both the Atlantic and Gulf sea
breezes are not expected to be particularly strong, so the
placement of outflow boundaries will be key to where convection
Some storms today could be locally strong to perhaps severe, with
frequent to excessive lightning, gusty winds 40-55 mph, and small
hail, although a storm or two may be able to produce hail
approaching severe limits. Waterspouts will also be possible over
the nearshore waters. Heavy rainfall will also be a threat with slow
moving thunderstorm clusters, with poor drainage and urban flooding
High temperatures will generally range from the upper 80s to lower
90s, with a few mid 90 readings possible in the interior where
convection holds off the longest. Heat index readings will generally
be in the 90s.
SHORT TERM /6 PM SUNDAY EVENING THROUGH MONDAY NIGHT/...
With the upper-level low lingering near South Florida, showers and
thunderstorms may last well into the night with the primary threat
being frequent lightning, as the loss of daytime heating will limit
hail and wind potential. Locally heavy rainfall will continue to be
a threat as well, with poor drainage flooding possible. Convective
coverage should begin to wane after midnight. Low temperatures will
generally be in the 70s.
The flow will shift slightly more to the southeast on Monday and be
a little stronger than recent days, with additional scattered to
numerous showers and thunderstorms mainly during the afternoon and
evening hours primarily over the interior and Gulf Coast. Midlevel
temperatures will warm back to seasonable levels, helping to reduce
the threat of strong storms with frequent lightning and heavy
rainfall the primary threats. Convective activity will begin to wane
during the evening hours as drier air begins to work into the
region. High temperatures will be slightly warmer on Monday, in the
lower to mid 90s except for upper 80s along the immediate Atlantic
coast. Low temperatures Monday night will range from the mid 70s to
LONG TERM /TUESDAY THROUGH SATURDAY/...
The long term period will feature mainly afternoon and evening
scattered showers and thunderstorms, with a continued easterly flow
keeping the bulk of the activity across the interior and Gulf Coast.
Model guidance and latest observed satellite analyses continue to
depict a potential intrusion of Saharan dust into the western
Atlantic, extending into South Florida beginning as early as Tuesday
and continuing through much of the work week. Despite this possible
dry air intrusion, a tropical wave approaching the eastern Carribean
and a slight weakening of the upper-level ridge may still allow for
scattered showers and thunderstorms. Will favor the drier end of
guidance at this time, but still keep a scattered threat and
continue to monitor.
Temperatures will be near normal for late July during the long term
A light east/southeasterly flow will prevail across the local
Atlantic and Gulf waters today, generally around 10 knots or less.
Locally higher winds will be possible in and around thunderstorms,
along with frequent lightning and rough seas. Seas are expected to
be 3 feet or less with little to no swell. The east/southeasterly
flow will begin to increase heading into next week, with minor
increases in seas possible.
Rip current risk will be low today for Atlantic and Gulf beaches,
but may increase by the midweek period with increasing
east/southeast onshore flow for Atlantic beaches.
VFR conditions will overall prevail with brief periods of mvfr cigs
associated with convective activity early this morning at APF and
even may be very brief IFR with storms impacting the airport
directly. But given uncertainty and nature of activity will handle
those with amendments as needed. For later today again VFR should
prevail but cannot rule out periods of MVFR cigs associated with
storms across the area this afternoon and early evening at all
sites. Very brief IFR cannot be ruled out either should a storm
impact any given site. Will handle with amendments as needed. SE
winds of 5-10 knots today will prevail at all sites except for a
slim chance of a sea breeze at APF late today. Light and variable
winds overnight and early morning all sites.
.PRELIMINARY POINT TEMPS/POPS...
West Palm Beach 89 76 90 78 / 50 30 60 10
Fort Lauderdale 88 76 89 80 / 50 40 50 20
Miami 89 77 90 80 / 50 40 50 10
Naples 87 74 89 77 / 50 20 50 30