textproduct: Key West

KEY MESSAGES

-Rain chances will remain elevated today.

-A strong cold front will blast through the Florida Keys on Saturday, with a line of showers expected along and just ahead of the frontal passage.

-Very cold and windy conditions are expected Saturday evening through at least Monday morning. A Wind Advisory and/or a Cold Weather Advisory may be required for portions or all of the Florida Keys.

DISCUSSION

Issued at 600 AM EST Fri Jan 30 2026 Isentropic analysis highlights upglide along the 292-298K potential temperature surfaces at this early morning hour. CIMSS MIMIC total precipitable water product depicts a region of enriched moisture south of the Florida Keys, with 850 mb geopotential height and vorticity analysis placing the Florida Keys in a weak area of cyclonic flow. Local KBYX Doppler radar is detecting scattered, generally light showers dotting portions of the Florida Keys as well as the marine zones south of the Island Chain. Temperatures have dropped little overnight owed to widespread mostly cloudy skies, with temperatures generally in the lower to mid 60s in the Lower and Middle Keys, and in the upper 60s in the Upper Keys.

Confidence is very high in the eventful forecast through the weekend. A strongly positively-tilted shortwave trough is progged to dive towards the Mid-Atlantic States today and this evening. Global ensemble mean products are in marked agreement that this will result in rapid cyclogenesis just offshore of the Carolinas on Saturday and Sunday. Closer to home, the sensible impact of this system will be a very strong cold front diving through the Florida Peninsula and the Florida Keys, with an arctic airmass in its wake for Saturday night through Monday. The interaction of high pressure building in the wake of the front with the deep cyclone off the Carolinas will support several hours of gale force winds across the Keys marine zones, and a rare Gale Watch has been issued for coastal waters. This will likely be upgraded to a Gale Warning on Saturday, and additional Wind Advisory and Cold Weather Advisory products may be required. Temperatures will be near- record levels during this period, with temperatures likely colder than we have seen in the Florida Keys in well over a decade.

High pressure will slowly slide eastward through the week, and the upper-level geopotential height pattern will flatten for several days. This will support slowly moderating temperatures through Thursday, before yet another coastal system may form off the Carolinas late in the week, driving another possible cold front through the Keys. Confidence in this long-term forecast is low at this time.

In the meantime, stay warm, Florida Keys residents and visitors.

MARINE

Issued at 600 AM EST Fri Jan 30 2026 Small Craft Should Exercise Caution in the Straits of Florida today. A Gale Watch is in effect for all Florida Keys coastal waters. From synopsis, gentle to moderate, northerly breezes will continue today and tonight. A strong cold front will blast through the Florida Keys marine zones on Saturday. Breezes will back to the northwest and dramatically freshen in the wake of the front. A period of gale- force winds is expected Saturday evening through Sunday morning across the Keys coastal waters, as high pressure building across the Gulf Coast interacts with the front. While breezes will slowly slacken and seas subside Sunday through Monday, marine hazards will continue. North to northeast breezes will slacken further on Tuesday, becoming gentle to moderate.

AVIATION

(06Z TAFS) Issued at 600 AM EST Fri Jan 30 2026 VFR conditions should prevail at both island terminals today with BKN to OVC decks based near 040-050. Occasional MVFR CIGs are possible at either airfield as light showers continue to wax and wane across the area, but extended periods of categorical impacts are not expected. Opting to maintain VCSH in the TAFs for now, and will amend for any stronger activity if necessary. North northeast breezes in the morning of 5 to 10 knots will peak at near 10 knots in the afternoon, and back to the north northwest over the second half of the TAF period.

PRELIMINARY POINT TEMPS/POPS

Key West 67 62 70 48 / 30 10 60 20 Marathon 68 60 68 43 / 40 10 60 20

KEY WATCHES/WARNINGS/ADVISORIES

FL...None. GM...Gale Watch through Saturday morning for GMZ031>035-042>044- 052>055-072>075.