textproduct: Key West

KEY MESSAGES

- Minor coastal flooding will continue through the next several days, especially in the Upper Keys. Minor to moderate coastal flooding may return across the Keys heading into the weekend with the approaching new moon.

- Rain chances will be near to below normal for the remainder of this week.

- Dew points are expected to decrease to near 70 degrees by this weekend due to breezes turning to light to gentle northerlies.

SHORT TERM

(Tonight through Saturday) Issued at 900 PM EST Thu Nov 5 2026 Weather conditions have been mostly quiet this evening as a broad area of high pressure centered over the Gulf is observed on satellite water vapor imagery, and is nudging into our forecast area. Low levels winds have persisted out of the northeast, which was important for a cloud streamer to set up off of Key West. The low level moisture noted on the 00Z KKEY sounding from this evening supported the development of a handful of streamers over our waters, and around the time of sunset, a very brief and very narrow waterspout was observed to the southwest of Higgs Beach. This waterspout was only visible for a few minutes before it dissipated. A few showers from a streamer off of the Everglades made it to the Lower Keys, specifically in the vicinity of Big Pine Key, and MRMS estimated rainfall amounts of up to half of an inch fell on those island communities. Unfortunately, there were no automated observations sites that reported precipitation amounts.

Overnight tonight, weather is expected to remain unremarkable. The high will continue to be the dominating feature, and this will support light breezes out of the northeast. GOES-19 Nighttime Microphysics imagery does show some lower level clouds moving across the Lower Keys, as well as a low level convergence band parallel to the island chain over the Florida Straits. The "more important" of the two is the isolated cluster of lower level clouds over the Lower Keys with respect to overnight lows. Considering the light winds and the mostly clear skies, there is an opportunity for some radiational cooling. Forecast temperatures are currently in the upper 70s, but some lower 70s would be possible if we radiate. Due to the very localized nature of our radiational cooling, we will opt to maintain the upper 70s in the advertised forecast with our caveat noted here. No updates or changes are needed with this nighttime update.

PREV DISCUSSION

Issued at 1247 PM EST Thu Nov 5 2026 Our perceivable weather through the weekend will be heavily influenced by the mid-level ridge axis which will transit eastward across the area through Saturday. MIMIC PWAT imagery shows a plume of drier air advecting towards the area from the northeast and this will likely show up well on this evening's 00Z sounding. Expect mostly sunny and warm conditions to persist through the weekend with highs in the lower to mid 80s.

To our north, a weak frontal boundary is currently oriented northeast to southwest across Georgia extending into the Gulf Coast region. This front will slowly drift towards our forecast area by Sunday as an upper-level trough ejects across the Great Lakes region. Forcing and moisture along and ahead of the front will be minimal by the time it reaches our area. Therefore, PoPs are currently sitting around 30% or less for early next week. If anything, we should see some relief from the humid conditions with dewpoints dropping to near 70 degrees at times this weekend. Model consensus begins to diverge by the middle part of next week with regards to the evolution of a southern stream trough across the Southeastern US, but there is at least some evidence that our rain chances could increase again throughout the week.

MARINE

Issued at 800 PM EST Thu Nov 5 2026 There are no watches, warnings, or advisories in effect along the Florida Keys local waters. However, a Coastal FLood Statement is in effect along the Upper Keys, so mariners should expect less clearance under fixed bridges around times of high tide. From synopsis, a weak ridge will stretch southwestward across the Florida Peninsula, keeping gentle northeast to easterly breezes tonight and tomorrow. Breezes will slacken heading into the weekend as the ridge weakens and shifts southward into South Florida and the Keys. There is a potential for brief nocturnal surges each night through the next several days. In addition, drier air filtering through the lower levels will keep near normal rain chances. A surface high will develop across the Gulf beginning Friday, which may lead to brief nocturnal wind surges along the west coast of Florida and into the outer Gulf waters.

AVIATION

(00Z TAFS) Issued at 800 PM EST Thu Nov 5 2026 VFR conditions with dry conditions onsite will prevail through the TAF period. Sky conditions will fluctuate between FEW and SCT around FL020, but MVRF CIG chances are very low, nearly zero.

PRELIMINARY POINT TEMPS/POPS

Key West 76 82 76 82 / 10 0 10 0 Marathon 77 83 76 83 / 10 0 10 10

KEY WATCHES/WARNINGS/ADVISORIES

FL...None. GM...None.