textproduct: Key West

KEY MESSAGES

- Major coastal flooding is expected again overnight, and a Coastal Flood Warning is in effect for all of the Florida Keys. Coastal flooding will gradually decrease over the weekend, but receding rates may be slow, especially in the Upper Keys.

- Gentle to occasionally moderate northeasterly breezes may see an uptick by Saturday evening, but an extended period of windy conditions similar to last weekend is very unlikely.

- There is increasing confidence in a wet, stormy period from Saturday Night through Monday.

UPDATE

Issued at 932 PM EDT Fri Oct 30 2026 Recent KBYX radar imagery shows isolated to scattered showers drifting southwestward across the southeast Gulf waters this evening, but this activity is low-topped and on the weak side and should generally fizzle out shortly. Mid/upper level moisture will be on a gradual increase overnight into Saturday as a southern stream shortwave swings across the Mississippi Valley. Meanwhile, freshening east-northeast breezes into Saturday and an increase in moisture should bring an uptick in shower coverage as speed convergence increases. The other item of interest overnight will be the coastal flooding impacts as the next high tide approaches after midnight, though water levels will likely be slightly less than the peaks in recent days. Thus, there is a chance that values may fall into Coastal Flood Advisory levels at least across some of the area, mainly in the Lower Keys so this will be something to monitor closely. Regardless, continued inundation of low lying property will still be a concern across the island chain despite water levels being on a slow receding trend in the coming days. Otherwise, no adjustments are needed to the forecast at this time as overnight lows fall to the upper 70s with partly cloudy skies.

DISCUSSION

Issued at 330 PM EDT Fri Oct 30 2026 Stubborn cloud cover defined weather across the Lower and Middle Keys this afternoon. While cloud cover dissipated over the Middle Keys shortly after 12 PM, skies remain broken to overcast across parts of the Lower Keys. Temperatures remained on the lower end for the Lower Keys, but the Upper Keys have observed temperatures rising into the upper 80s. Breezes along the reef continue to oscillate between light to gentle and gentle to moderate. Radar wise, very few if any meteorological echoes are present on KBYX returns. The weather pattern is rather stagnant across the Keys tonight. It is unlikely we will see a significant change in the next 12 hours, so a persistence forecast is apt. While quieter weather is preferred for anyone planning early Halloween festivities, coastal flooding continues to be the main hazard across the island chain. Another night of tides 2.0 to 2.3 feet above normal high tide looks likely, thus the Coastal Flood Warning is still in effect across the Keys. Remember to take precautions and plan around the time of peak tides!

Two features are expected to phase together this weekend. First, an upper level trough over south Texas will make its way across the Gulf towards the Keys. This piece of vorticity will be able to bring additional upper level moisture to South Florida on Sunday to Monday. The second feature is a developing high pressure system over the eastern US. Broad ridging is building over the east half of the continent, and the surface reflection is expected to center itself over New England by Sunday. Recent statistical model runs suggest moderate to fresh breezes are possible Sunday to Monday. Low level wind speed convergence from the freshening breezes would provide the lift and the upper level trough would supply the moisture. Currently, we expect likely showers with a chance of thunderstorms Sunday night through Monday. The main concern from this potential bout of rainfall will be coastal flooding. While tides are on track to slowly recede this week, any amount of localized heavy rainfall will exacerbate flooding problems. Rainfall associated with this system is not expected to be organized as part of a frontal boundary, so impacts are likely to be heavily localized.

A drier period is expected to set up across the Keys to start early November. The Texas trough will moves off into the Atlantic and ridging will build over the western Gulf. A period of rather uneventful weather is expected for the Florida Keys through mid- week. Model ensembles do, however, show a possible frontal boundary moving across the Keys late next week. While a weather feature of some sort is expected, there is low confidence in what specifically will move across the Keys. Model ensembles from the GFS and ECMWF both washed out the feature because individual members showed very different solutions. Current forecasts assume this feature would be identified as a cold front. Regardless, there is a lot of uncertainty with next weekend's forecast. We will have a better idea of what this front will do at the start of next week, so check back after early November's round of showers.

MARINE

Issued at 330 PM EDT Fri Oct 30 2026 There are no watches, warnings, or advisories in effect for the Florida Keys local waters. However, significantly higher than normal high tides will result in reduced clearance under fixed bridges around times of high tide, so mariners are encouraged to keep that in mind.

From synopsis: A high pressure system is developing over the eastern half of the United States. The high will be able to support moderate to fresh breezes across the Florida Keys waters this weekend, and Small Craft Should Exercise Caution headlines may be required for all the marine zones. While the pressure gradient will not be sufficient to keep moderate to fresh breezes for the entire weekend, northerly swell from the Atlantic Ocean will keep waves elevated through the early part of the week. Shower chances will peak Sunday through Monday. Drier conditions will set up mid week, and breezes are on track to slacken to light to gentle.

AVIATION

(00Z TAFS) Issued at 932 PM EDT Fri Oct 30 2026 VFR conditions will generally prevail throughout the TAF period, though isolated to scattered SHRA may occur by Saturday afternoon. VCSH has been added to both terminals after around 16Z Saturday as precip chances increase. Otherwise, winds will be out of the ENE at around 7-10 kts through the period with occasional stronger gusts by late Saturday.

CLIMATE

On this day in Keys Weather History, in 1910, the daily record low temperature of 59F was recorded in Key West. This is also tied for the coldest temperature ever recorded in October. Temperature records for Key West date back to 1872

KEY WATCHES/WARNINGS/ADVISORIES

FL...Coastal Flood Warning until 5 AM EDT Saturday for FLZ076>078.

GM...None.