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
688
FXUS62 KKEY 010931
AFDKEY

Area Forecast Discussion
National Weather Service Key West FL
531 AM EDT Mon Jun 1 2026

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

.KEY MESSAGES...

- Early morning showers today will break up around sunrise, but
  there is a 20% to 30% chance for some more showers and
  thunderstorms later today.

- While highs will be seasonably warm in the upper 80s through at
  least mid week, lows will remain warmer than normal, providing
  little relief from the heat in the overnight hours.

- The next opportunity for an uptick in active weather looks to be
  the middle of the week.

&&

.DISCUSSION...
Issued at 530 AM EDT Mon Jun 1 2026
Another warm and muggy night is almost behind us along the Florida
Keys. Overnight lows only dipped into the lower and mid 80s,
except near Key Largo where rain cooled air was able to bring
temperatures to the upper 70s. Dew points in the upper 70s kept
heat index values overnight anywhere from near 90F to the upper
90s. Over the past few hours, there has been an uptick in activity
on our KBYX radar. It looks like an area of convergence around the
Lower and Middle Keys ignited a couple of lines of showers with
isolated thunderstorms embedded in both lines. Even though we
have a generally variable wind field near the surface, the flow
aloft was able to move this activity northeast to easterly. Early
risers may see some a few raindrops on their way out the door this
morning, but there should be a break in rain by sunrise.

As the day goes on, a few factors are at play as to whether or not
there are more showers. Similar to the past few days, winds along
the island chain may assume a southwesterly direction due to
daytime heating. If this southwesterly wind is sustained just long
enough, a reverse cloudline could develop. The skinny forecast
soundings suggest that any individual shower could become an
efficient rain-producer, and this goes for cloudlines too. Another
factor will be colliding residual boundaries that have been noted
on radar. Any boundary collision could trigger new shower
activity. All of this is to say that someone is going to see rain
today, it`s just a matter of who? Since the Middle and Upper Keys
currently have a few outflow boundaries at play, as well as the
potential for afternoon showers from mainland convection in the
afternoon, we`ll advertise a chance of showers (around 30%) for
these communities. For the Lower Keys, we`re betting on the
lingering activity from this morning, and once this fizzles out we
may be done for the day, so we`ll advertise a 20% chance for these
communities.

How the middle of the week plays out will depend on the evolution
of troughing down the east coast. The most recent model runs have
the frontal boundary associated with this trough stalling around
the middle of the peninsula. The closer that front can get, the
better lift we will see in the environment, so this will impact
rain and thunder chances. Either way, the best chances for
showers and thunderstorms look to be on Wednesday and Thursday.
This front doesn`t look like it will be able to get close enough
to bring drastically drier air, but knocking off a few degrees
from our dew point will make the air feel just a little bit less
muggy. After the parent trough had the opportunity to lift away
from the area, closer to normal conditions will be able to settle
in.

&&

.MARINE...
Issued at 530 AM EDT Mon Jun 1 2026
There are no watches, warnings, or advisories in effect for the
Florida Keys local waters. From synopsis, weak high pressure
across the area will support light to gentle breezes going back
and forth between southwest to northwest over the next couple of
days. Near normal rain and thunder chances also expected. A weak
frontal boundary may stall near the Keys coastal waters by mid
week, supporting an uptick in breezes as well as rain chances.

&&

.AVIATION...
(06Z TAFS)
Issued at 530 AM EDT Mon Jun 1 2026
Lingering cloud cover from nighttime showers may lead to
occasional MVFR CIGs at the start of the TAF period, but
prevailing conditions will be VFR through the TAF period. There
low uncertainty regarding where showers will pop up in the
afternoon, so opting to keep the TAFs dry until organized
convection can initiate. Surface winds will remain light and
variable.

&&

.OF NOTE IN KEYS WEATHER HISTORY...
On this day in 2004, the official groundbreaking of the new WFO
Key West facility took place.

&&

.KEY WATCHES/WARNINGS/ADVISORIES...
FL...None.
GM...None.
&&

$$

Public/Marine/Fire...DP
Aviation/Nowcasts....DP
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