Update AFD Area Forecast Discussion — Sat Apr 4, 2026 4:27 AM

AFDKEY

Area Forecast Discussion
National Weather Service Key West FL
422 AM EDT Sat Apr 4 2026

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

.KEY MESSAGES...

- Breezy conditions will continue through at least this evening.
  A Small Craft Advisory is in effect for all Florida Keys marine
  zones.

- A drier pocket of air will help to keep significant rainfall at
  bay with only spotty, isolated showers expected through the
  weekend.

- High confidence for an increase in shower coverage by Tuesday to
  Wednesday. Breezy to Windy conditions expected by Tuesday night
  to Wednesday.

&&

.DISCUSSION...
Issued at 425 AM EDT Sat Apr 4 2026
Dry conditions appear well established across the Florida Keys
for the first weekend of April. KBYX radar returns just after
midnight highlighted a line of disorganized showers north of the
Lower Keys, but that activity has since dissipated. Nighttime
microphysics observations from GOES East detect lines of shallow
cumulus across the Keys nearshore waters, nothing indicative of
heavy showers or thunderstorms. A glace at the GOES East derived
precipitable water highlights a tongue of dry air extending south
towards the Upper Keys from the Outer Banks. The Atlantic High is
still in place for today, which is responsible for the pressure
gradient maintaining fresh easterly breezes along the reef. The
weather pattern suggests today will be slightly warmer than normal
with sustained breezy conditions.

.FORECAST...
A mid latitude cyclone deepening over the Great Lakes will start
to change the weather pattern over the northeastern US. There is
high confidence this low pressure system will have enough energy
to displace the Atlantic High and weaken the broad ridge that has
maintained the breezy conditions across the Florida Keys by Sunday
to Monday. Slackening winds does not mean the direction is likely
to shift, and low level moisture is forecast to wash over the
Keys through Sunday to Monday.

Early next week, model guidance suggests the cold frontal boundary
associated with the Great Lakes low will move into the Gulf. What
remains of the boundary could reach the Florida Keys by mid week
and provide a source of lift for showers and thunderstorms.
A well developed high over the eastern United States would be
responsible for pushing the frontal boundary south, and guidance
suggests high confidence in another breezy to windy period for the
Keys next week, possibly as early as Tuesday night. Models do not
show consensus on the strength of these winds at this time. The
spread from the NBM shows a range of over 20 mph at EYW for
Wednesday and Thursday, so details are still up in the air. The
good news is that model guidance gives medium to high confidence
in a more favorable environment for midweek rainfall. Considering
the extended drought conditions, any precipitation would be much
appreciated.

&&

.MARINE...
Issued at 425 AM EDT Sat Apr 4 2026
A Small Craft Advisory is in effect for all the Florida Keys
coastal waters. From synopsis, a broad Atlantic high will begin to
weaken and move east during the first half of the weekend. There
is high confidence that moderate to fresh easterly breezes will
slacken during the weekend. Light to gentle breezes early next
week will freshen by Wednesday in response to a strong 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...
(06Z TAFS)
Issued at 425 AM EDT Sat Apr 4 2026
VFR conditions will prevail at both EYW and MTH for the 06Z TAF
period. Near surface easterly winds will remain in the 15 to 20
knot range with occasional to frequent gusts. Crosswind concerns
are low for this pattern. Isolated shower activity and occasional
periods of MVFR CIGs are possible, but at low enough confidence to
not warrant a TEMPO.

&&

.PRELIMINARY POINT TEMPS/POPS...
Key West  82  73  83  72 /  10  20  10  20
Marathon  82  73  82  73 /  20  20  20  20

&&

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

&&

$$