Update AFD Area Forecast Discussion — Sat Apr 4, 2026 10:09 PM

AFDKEY

Area Forecast Discussion
National Weather Service Key West FL
1002 PM EDT Sat Apr 4 2026

...New DISCUSSION, MARINE, AVIATION...

.KEY MESSAGES...

- Breezy conditions will continue overnight, before winds
  decrease for the remainder of the weekend. A Small Craft
  Advisory remains in effect for all Keys marine zones.

- Although passing showers are possible, especially overnight,
  significant rainfall is not expected through the weekend.

- There is increasing confidence for above normal shower and
  possible thunderstorm chances for Tuesday and Wednesday. Breezy
  conditions are expected once again by Tuesday night.

&&

.DISCUSSION...
Issued at 1000 PM EDT Sat Apr 4 2026
Deep mean layer ridging remains in place across the western North
Atlantic. The center of this ridge was near Bermuda with the
western side of this ridge extending westward into Florida and
the eastern Gulf. Marine observations platforms surrounding the
Island Chain are recording easterly breezes near 20 knots as a
result. CIMSS Mimic Precipitable Water (TPW) products shows a slug
of deep moisture currently streaming westward through the Bahamas
and along the northern coast of Cuba. The leading edge to this
deeper moisture is just beginning to encroach on the Keys this
evening. KBYX radar has remained active through the afternoon and
evening with occasional showers affecting the Island Chain from
time to time. For the most part, this activity has remained across
the marine area. GOES 19 Nighttime Microphysics imagery shows
stratocumulus moving from east to west through the Keys resulting
in partly cloudy skies. Temperatures along the Island Chain are in
the mid to upper 70s and dew points are near 70 degrees.

.SHORT TERM FORECAST...
The 00z evening sounding shows decent low level moisture before
drying out some above 900 mb and then drying out even further
above approximately 725 mb. The sounding is unstable with lapse
rates of 5-7 degrees Celsius per km and CAPE values around 1200
J/kg. While we have increasing moisture moving into the area, the
more robust upper level support is anticipated to remain east of
the area across the Bahamas. Therefore, even though, we will see
an increase in moisture, showers may become more widespread, but
thunder will remain minimal. There might be a shower or two that
is able to become a thunderstorm overnight but the trigger needed
to really get things going is expected to stay east. Therefore, we
have moisture and instability across the area but lack the trigger
or upper level energy to support more robust convection. If all 3
of these synced up, it would be off to the races tonight. Also,
due to the slug of moisture moving in, PoPs were increased for the
Sunday to Monday time frame this update and might need to be
increased further. Due to the breezy conditions and partly cloudy
skies along with nuisance showers, min temperatures were also
increased from lower to mid 70s for overnight. Breezy conditions
were also extended through the overnight since gusts are still
approaching near 20 knots.

&&

.MARINE...
Issued at 1000 PM EDT Sat Apr 4 2026
A Small Craft Advisory remains in effect for all the Florida Keys
coastal waters. From synopsis, a broad Atlantic high will
continue to weaken and move eastward. There is high confidence
that moderate to fresh easterly breezes overnight will slacken by
Sunday morning. Light to gentle breezes early next week will
freshen once again by Wednesday in response to a strong second
area of high over the eastern United States. A chance of showers
will return to the forecast by Monday night, and thunderstorms are
possible after the start of the work week.

&&

.AVIATION...
(00Z TAFS)
Issued at 1000 PM EDT Sat Apr 4 2026
VFR conditions are expected to prevail at both EYW and MTH
terminals through the TAF period. There are some indications for
occasional periods of MVFR CIGs overnight with a potentially
longer period of MVFR CIGs during the day on Sunday. While a
shower or two cannot be ruled out for either terminal overnight or
Sunday morning, latest guidance suggests a better chance for
showers Sunday afternoon into Sunday evening. Due to the low
confidence in timing and placement, VCSH was left out of the TAF
for now.

&&

.PRELIMINARY POINT TEMPS/POPS...
Key West  82  73  83  73 /  10  20  20  30
Marathon  82  73  82  74 /  10  30  30  30

&&

.KEY WATCHES/WARNINGS/ADVISORIES...
FL...None.
GM...Small Craft Advisory until 5 AM EDT Sunday for GMZ031>035-
     042>044-052>055-072>075.

&&

$$