Scientific Forecaster Discussion
fxus62 kmfl 251710
Area forecast discussion
National Weather Service Miami Florida
110 PM EDT Tue Jun 25 2019
generally VFR outside of afternoon/evening showers & storms. Sea
breezes are expected to push inland today, helping to spur
convection. Terminals could see bouts of sub-VFR conditions around
convection. Higher storm chances are over southern portions of the
area today. Convection should trend down after sunset with light
wind flow returning overnight though a few storms could push
towards apf this evening. A wildfire inland of fll/fxe will need
to be monitored in case the smoke blows back towards a terminal
overnight into the morning.
Previous discussion... /issued 1128 am EDT Tue Jun 25 2019/
.Hot and stormy afternoon and evening today...
.wildfire smoke could impact Broward and Palm Beach...
a wide variety of meteorological concerns today with heat, smoke
from a wildfire, and the potential of strong storms on the docket.
Let's begin with the heat as stifling low level moisture, a lack
of flow, the tardy start to the sea breeze, and plenty of
sunlight to push many areas beyond or close to heat advisory
criteria. Have added Palm Beach County to the heat advisory and
will continue to monitor the other areas. The main reasoning for
Palm Beach County is the lack of any moderating force (broward and
Miami-Dade did see some convection yesterday to help refresh the
atmosphere a bit).
Meanwhile in inland Broward, a wildfire continues to burn acres of
everglades. The morning southwesterly flow pushed the smoke
towards Palm Beach County this morning and the shifting wind could
direct the smoke to other areas including parts of metropolitan
Broward through the day. This will need to be monitored,
particularly overnight, but the Florida Highway patrol has not
reported any major obstructions to visibility on area highways.
Moving on to the afternoon and evening, a ripe atmosphere could
support strong to severe storms today. Lapse rates aloft are
capable of supporting strong updrafts and temperatures are cool
enough to permit hail formation. Add in the influence of the sea
breeze and other boundaries hanging out around the area and there
might be strong to severe storms with damaging winds and hail
later today. Updated the severe weather potential statement to bring the threats a bit closer to
the East Coast in case the sea breeze continues its tardy trend
lately. Future updates may be needed if the threat materializes a
bit more intensely than currently forecast.
Have a pleasant Tuesday!
Previous discussion... /issued 747 am EDT Tue Jun 25 2019/
generally VFR and light wind flow until the sea breeze develops
later today. As the sea breeze advances inland, showers and
thunderstorms will develop with a focus on the afternoon and early
evening hours. Light winds and fair weather return overnight with
a general repeat of the pattern for Wednesday.
Previous discussion... /issued 245 am EDT Tue Jun 25 2019/
today through Wednesday : with a wildfire across portions of The
Everglades in Broward County, areas of patchy smoke are possible
early this morning, especially with winds favoring the lighter side.
We will continue to monitor in case for the off chance of issuing a
dense smoke advisory, but at this time, that doesn't look likely.
Otherwise, deep layer high pressure centered to our west will remain
the dominant influence on our weather once again today. Low-level
flow will remain weak enough for both the Atlantic and Gulf sea
breezes to develop and move inland this afternoon, bringing isolated
to scattered shower and thunderstorm chances to mainly the interior
and western portions of the East Coast Metro areas. GFS forecast
500 mb temps look to be a tiny bit warmer than average for the
next couple of days, but the possibility of strong storms cannot
be ruled out, especially as forecast lapse rates look to be
conditionally unstable and diurnal heating/sea breeze collision
takes place. With that in mind, frequent lightning, small hail,
and gusty winds will be possible with the stronger storms.
Wednesday we will begin to see the ridge of high pressure
eroding and retrograding away from Florida with winds becoming
more easterly. As this occurs, rain chances will be on the rise
and coverage will be more widespread with a more diurnal
convective summertime pattern in place. The only caveat here is
that models are indicating Saharan dust will drift back southward
across the peninsula back into South Florida. If this were to
happen, rain chances could possibly be lower than expected, though
storms tend to be stronger and more organized due to stronger
updrafts and smaller/thicker anvils. At this time, favoring the
higher end pops (50 to 60%) due to the favorable pattern for
convection, but will continue to monitor.
Hot temperatures remain the main story over the next few days as
highs climb into the mid to upper 90s. This will send heat index
values soaring up above 100 degrees by late morning, with many
areas remaining in the 100-106 degree range through the afternoon.
It appears that Collier and Mainland Monroe counties should again
reach heat advisory criteria of 108 degrees for two hours or
more, so an advisory is in effect for these areas today. Coastal
Palm Beach County and perhaps interior Miami-Dade County may reach
heat advisory conditions today as well, but confidence is too low
to include at this time. We will keep an eye on temperatures in
these areas as the morning progresses and an additional advisory
may be warranted later. Regardless of whether or not your area is
in an advisory, be sure to slow down and take breaks if you're
spending time outdoors.
Thursday through Monday : the deep layer ridge gradually retrogrades
away from Florida allowing the steering flow to become more easterly
with time (veering more southerly by early next week). This will
bring US back into a diurnal shower/thunderstorm cycle with
overnight/morning Atlantic showers followed by afternoon interior
and West Coast thunderstorms. However, as we move into the end of
the week into the weeekend, we will have to monitor the progression
of a tropical wave well to the south (in the carribean) of Florida
as it will bring in deep tropical moisture associated with a
trough that looks to break off from the wave. This will lead to
increased rain chances, higher coverage, and a wetter pattern for
the end of the week into the weekend. There will be some relief of
the high temperatures with the increased cloud cover and rain
chances as temperatures will be back closer to normal.
generally favorable boating conditions are expected through mid-
week. Mid-week through the end of the week, chances for showers
and thunderstorms will be increasing along with coverage. Seas
will be generally 3 feet or less.
Preliminary point temps/pops...
West Palm Beach 78 92 78 90 / 20 30 20 30
Fort Lauderdale 80 91 80 88 / 20 40 30 30
Miami 80 92 79 90 / 20 50 30 30
Naples 78 93 76 91 / 20 40 30 50
Florida...heat advisory until 7 PM EDT this evening for flz067>070-075-168.