Area forecast discussion
National Weather Service Miami Florida
803 PM EDT Wednesday Jun 19 2013
Update...
showers and thunderstorms were beginning to diminish across South
Florida early this evening. An outflow boundary from earlier
convection across the interior was moving southeast across Miami-
Dade County and sparking isolated showers. This activity should
continue to wind down this evening...with partly cloudy skies and
warm temperatures overnight. Hazy skies are possible on Thursday
as Saharan dust continues to move across South Florida. Only
changes to the forecast this evening were to remove probability of precipitation after
midnight...and lowered temperatures a couple degrees across the
interior.
&&
Previous discussion... /issued 730 PM EDT Wednesday Jun 19 2013/
Aviation...
the interior showers and thunderstorms have mostly dissipated
early this evening...except for some light to moderate rains over
the western interior areas and isolated showers over the eastern
interior areas. These showers over the eastern interior areas
could move east into the East Coast taf sites before dissipating
this evening. So will leave a vcsh in for the East Coast taf sites
until 03z tonight before going dry for rest of the night. Kapf taf
site should remain dry for tonight.
The weather on Thursday should remain dry over the taf sites...due
to drier air working into the area along with the sea breezes
developing and pushing inland.
The winds tonight will remain easterly at all of the taf sites
with the winds decreasing to 5 knots or less by 03z. The winds
will then remain less than 5 knots through 13z on
Thursday...before increasing to around 10 knots by 16z. The only
exception to this is for kapf taf site where the winds will become
westerly around 15z on Thursday...due to the West Coast sea breeze
developing and pushing east.
The ceiling and visible will also remain in the VFR conditions tonight
into Thursday over all of the taf sites.
Aviatiion...54/bnb
Previous discussion... /issued 231 PM EDT Wednesday Jun 19 2013/
Short term (tonight-Friday night)...
early afternoon showers and thunderstorms have already begun to
initiate across portions of the local area as the east and West
Coast sea breezes begin to penetrate inland. Some of this activity
appears to have been enhanced by a middle-level vorticity progressing
eastward from Lake Okeechobee earlier...which showed up well on the
visible satellite loop. The latest hrrr and WRF model reflectivities
appear to be initializing well with the latest radar trends and
generally indicate this early afternoon activity continuing to
develop and becoming concentrated across the interior and western
locations through the late afternoon and early evening periods as
the sea breezes boundaries penetrate farther inland and merge.
Although middle-level lapse rates and 500 mb temperatures are not very
impressive today...a few storms may become strong with the main
threat being gusty winds up to 45 miles per hour.
Tonight through Friday night...the general trend with above average
temperatures will persist...especially through the overnight hours
when temperatures are forecast to remain several degrees above
average. As a result...warmer minimum temperature records could be
broken each night. Model precipitable water values indicate a slight
drying trend Thursday through Friday ahead of an approaching
tropical wave with values trending down to around 1.5".
However...daytime heating combined with southeast low-level flow up to 700 mb
around the subtropical ridge axis will be enough to support another
round of isolated/scattered afternoon showers/tstms...especially across the
interior locations through the late afternoon and early evening
periods. Hazy conditions due to higher concentrations of dust
spreading into the area from the southeast will remain possible each
day.
Long term (saturday-tuesday)...
models remain persistent from run to run and continue to indicate a
tropical wave approaching and moving through the area over the
weekend. Model precipitable waters associated with this wave are forecast to near
the 2" mark by Sunday...which should translate to higher rain
chances. Conditions should trend back to normal through the early
half of the upcoming week as the wave tracks west and away from the
local area.
Aviation...
VFR conditions will prevail throughout the forecast period. Winds
will remain out of the east southeast between 10 to 15 knots this
afternoon and this evening across the East Coast terminals.
Scattered showers and thunderstorms will continue to develop this
afternoon mainly west of the East Coast terminals. At kapf, a West
Coast sea breeze will develop later this afternoon. Winds will
diminish across all terminals this evening and then they will
increase again by the middle of Thursday morning.
Marine...
light to moderate southeast winds associated with high pressure will
persist through the week. The best chance for isolated showers and
storms will be through the overnight and early morning hours each
day. A weak tropical wave will approach and move through the marine
area over the weekend and may translate to better shower/thunderstorm
coverage.
Fire weather...
relative humidities are forecast to remain above critical levels
each day. Light southeast winds are expected to persist through much
of the week...except through the afternoon periods as the Gulf Coast
sea breezes penetrates inland across portions of Collier County.
&&
Preliminary point temps/pops...
West Palm Beach 77 87 78 88 / 20 20 20 20
Fort Lauderdale 80 89 81 89 / 20 20 20 20
Miami 78 89 80 89 / 20 20 20 20
Naples 75 92 74 93 / 20 30 20 30
&&
Mfl watches/warnings/advisories...
Florida...none.
Am...none.
GM...none.
&&
$$
Discussion/marine/fire...84/AK
aviation/radar...54/bnb
