Area Forecast Discussion
Issued by NWS Key West, FL

Home |  Current Version |  Previous Version |  Text Only |  Print | Product List |  Glossary On
Versions: 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29
438
FXUS62 KKEY 170258
AFDKEY

Area Forecast Discussion
National Weather Service Key West FL
1058 PM EDT Mon Sep 16 2024

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

.DISCUSSION...
Issued at 1058 PM EDT Mon Sep 16 2024

This evening roughly mirrored yesterday, with the afternoon
featuring a reverse cloud line followed by a stark decrease in
coverage. The main difference tonight is the broad area of
activity over Cuba and the outflow boundary from this convection
moving into our distant waters. The long stretch of light and
generally variable winds is continuing across the Florida Keys
forecast area. Temperatures have struggled to drop further than
the upper 80s in most island communities and dew points are still
in the upper 70s, making for quite a humid evening. Looking to
our north, isolated showers are situated along a stationary
boundary draped across Central Florida. Even farther north,
Potential Tropical Cyclone Eight (PTC 8) is centered over the
Carolina coast.

For tonight, a few boundaries still lingering across our area
could ignite and produce showers and potentially a few
thunderstorms. The main story for the night will be deep tropical
moisture being pulled across our area as PTC 8 starts to merge
with an upper trough. While most of the unsettled weather is
expected during the day tomorrow, convection could begin to ramp
up earlier tomorrow morning. Due to the uncertainty in the exact
set up and location of the aforementioned synoptic features, have
decided not to waiver on the 40% rain chances, especially with the
already unstable environment that was sampled by the 00Z
sounding. The forecast remains on track and no changes were
necessary.

&&

.MARINE...
Issued at 1058 PM EDT Mon Sep 16 2024

There are no watches, warnings, or advisories in effect for the
Florida Keys coastal waters. Light and generally variable breezes
will continue through Saturday across the Florida Keys coastal
waters. Winds and seas will be elevated in and around
thunderstorms, particularly on Tuesday and Wednesday, though
background winds will remain light and variable. Northerly swell
generated by Potential Tropical Cyclone Eight currently centered
across the Carolinas will linger through Tuesday and Wednesday.
This disturbance will deepen into an upper-level trough and
slowly slide south towards the Florida Peninsula through Saturday.
Unpredictability in the movement of this trough means confidence
in the extended forecast is very low.

A Coastal Flood Advisory remains in effect for the Upper Keys,
and a Coastal Flood Statement remains in effect for the Middle and
Lower Keys. Boaters can expect less clearance under fixed bridges.

&&

.AVIATION...
(00Z TAFS)
Issued at 1058 PM EDT Mon Sep 16 2024

VFR conditions will prevail tonight, but conditions will begin to
deteriorate by tomorrow morning. Convective coverage is expected
to increase by around 12Z tomorrow, so VCSH has been included to
account for this. As confidence in this timing increases, TEMPOs
will likely be added to the TAFs. Outside of convection, winds
will generally be light and variable overnight before becoming
east to southeast by tomorrow.

&&

.CLIMATE...
On this day in 2023, the daily record high temperature of 97F was
recorded. This is also tied for the warmest temperature ever
recorded in the month of September for the Marathon area.

&&

.PRELIMINARY POINT TEMPS/POPS...
Key West  82  89  82  89 /  40  60  60  50
Marathon  82  90  81  89 /  40  60  60  50

&&

.KEY WATCHES/WARNINGS/ADVISORIES...
FL...Coastal Flood Advisory for FLZ076.

GM...None.
&&

$$

Public/Marine/Fire...NB
Aviation/Nowcasts....NB
Data Acquisition.....DR

Visit us on the web at weather.gov/key

Follow us on Facebook and Twitter at:
www.facebook.com/nwskeywest
www.twitter.com/nwskeywest