Scientific Forecaster Discussion

Return to Local Conditions & Forecast

Without Abbreviations
With Abbreviations

fxus62 kmfl 231202 
afdmfl

Area forecast discussion
National Weather Service Miami Florida
802 am EDT sun Apr 23 2017

Aviation...
MVFR conditions should improve through the morning as intermittent
showers surrounding a low pressure area push across the region.
Improvement is expected to begin over southern terminals and
spread north and westward towards pbi and apf. A second or third
round of sub-VFR showers is possible, but confidence in an impact
to a terminal is not high enough to include any long-range
restrictions at this issuance. Short-fused amendments will likely
be required through much of the day.

&&

Update...
most of the scattered to numerous showers have been lifting
northward out of Miami-Dade and Broward as the weak surface low
tracks northeastward across South Florida. Most of the rain is
located in northern part of the County Warning Area and over the Gulf and Atlantic
waters. Therefore have adjusted pops to show this with updated
zones to follow shortly.

&&

Previous discussion... /issued 401 am EDT sun Apr 23 2017/

Discussion...

Short term /today through Tuesday/
scattered to numerous showers have expectedly overspread South
Florida overnight, with some areas receiving up to 1 inch of
rainfall. Most widespread activity has remained over Florida
Keys, and expect this activity, associated with weak surface low
pressure center to mainly move northeastward and remain offshore.
Still though, next 12 to 18 hours look pretty wet, as pwats remain
close to 2 inches. Few thunderstorms remain possible, and embedded
convection is already occurring. Dont expect any intense
thunderstorms, just cloud-to-ground risk into the evening, as instability will
be quiet modest. Diurnal heating will be curbed by overcast
conditions with precipitation, thus maxima will likely be in low
80s.

As low pressure and associated moisture plume are shunted to the
east by approaching high pressure, drier air will move into the
region tonight and especially Monday. Winds will veer westerly and
ahead of a cold front, with ample sunshine temperatures will
soar, reaching upper 80s toward 90f on the East Coast. Frontal
passage in the evening could have isolated showers with it, but
little low-level convergence and moisture void should preclude
anything too significant. A thunderstorm cant be ruled out, but
at this point probability looks too low to warrant keeping thunder
in grids. Monday and and Tuesday, expect west wind, mostly clear
skies, and seasonably warm temperatures.

Long term /Tuesday night through Friday night/
upper level trough will close off over the mid-Atlantic Tuesday
night then drift into the northeast Continental U.S. Wednesday and Thursday.
This will keep South Florida in dry west/southwest pattern as high
pressure settles in. Winds turn again to the southeast Thursday
and Friday. Temperatures will rise to levels slightly above
normal, well into the 80s with a few spots, especially out west
at week's end, reaching low 90s. Minima will be 60s, with 70s in
the urban areas east.

Marine...
low pressure moving through the area today and tonight will bring
winds from variable directions, but speeds outside of any isolated
thunderstorms should remain under 20 knots. As low pressure
departs to the north and east, winds turn west Monday. Cold front
moves through Monday night, reinforcing dry westerly flow through
mid-week. Seas and winds may briefly elevate behind this front,
but at this point levels don't look to be hazardous.

Aviation...
pockets of light-moderate rain showers ongoing with ceilings/visibilities generally
remaining VFR at the moment. Similar conditions expected to
continue through early this morning. Vcsh for most of the sites,
with occasional MVFR cigs in heavier activity. The only exception
to this is at kapf and kpbi taf sites, where the showers will not
get going until after sunrise. Increase in steadier rain with
embedded ts expected from south to north after 08z, mainly
affecting East Coast sites, with prevailing MVFR cigs around
fl030-035. East-southeast winds around 10 kts overnight except kapf which
will remain vrb05kt through cycle. Atlantic sites will see southeast
winds increasing to 10-13kts after 14z outside of convection, but
should turn more southwest between 18z and 21z at kmia, ktmb, and
kopf taf sites.

Beach forecast...
remnant wave action and coastal resettling will continue to lead
to favorable conditions for rip currents on Atlantic waters today,
and with 2 feet northeasterly swell entering the waters, high risk
of rip currents continues through today. Winds will turn westerly
early this week, reducing risk on Atlantic waters but
possibly increasing risk on Gulf waters.

Fire weather...
poor dispersion today but otherwise moist conditions relative to
past week or so. Rainfall amounts of up to an inch or so are
possible today, before drier weather moves in. At this point,
deterministic forecast has relative humidity values and wind
speeds just barely avoiding fire weather criteria across Collier,
Hendry, and Glades counties Tuesday through Thursday, so needless
to day, forecast conditions in these areas will be closely watched
over the coming days for the potential need for a Fire Weather
Watch.

&&

Preliminary point temps/pops...
West Palm Beach 82 70 88 66 / 70 30 20 0
Fort Lauderdale 82 72 89 69 / 60 30 20 0
Miami 83 72 89 70 / 60 30 20 0
Naples 82 72 81 65 / 70 10 10 0

&&

Mfl watches/warnings/advisories...
Florida...high rip current risk through this evening for flz168-172-173.

Am...none.
GM...none.

National Weather Service Glossary of Abbreviations