Straits of Florida from Halfmoon Shoal to 20 NM west of Dry Tortugas out 20 to 60 NM Marine Forecast
| Tonight...Northwest To North Winds Near 15 Knots. Seas 3 To 4 Feet, Occasionally To 5 Feet. Wave Detail: North 3 Feet At 7 Seconds. |
| Thursday...North Winds 10 To 15 Knots, Decreasing To Near 10 Knots. Seas 2 To 4 Feet, Occasionally To 5 Feet, Subsiding To 2 To 3 Feet. Wave Detail: North 3 Feet At 6 Seconds. |
| Thursday Night...North Winds Near 10 Knots, Becoming North To Northeast. Seas Around 2 Feet. Wave Detail: Northwest 2 Feet At 6 Seconds And Northeast 2 Feet At 6 Seconds. |
| Friday...Northeast Winds Near 5 Knots, Becoming Variable. Seas 1 To 2 Feet. |
| Friday Night...Variable Winds Near 5 Knots. Seas 1 To 2 Feet. |
| Saturday...Variable Winds Near 5 Knots. Seas 1 To 2 Feet. |
| Saturday Night...Variable Winds Near 5 Knots, Becoming Southwest To West 5 To 10 Knots. Seas 1 To 2 Feet. |
| Sunday...Southwest To West Winds Near 10 Knots, Becoming West To Northwest Near 15 Knots. Seas 1 To 2 Feet, Building To 2 To 3 Feet. Isolated Showers. |
| Sunday Night...Northwest Winds 10 To 15 Knots. Seas 2 To 3 Feet. Isolated Showers. |
| Monday...North Winds 10 To 15 Knots. Seas 2 To 3 Feet. |
| Monday Night...Northeast Winds Near 10 Knots. Seas 2 To 3 Feet. |
| Area Forecast Discussion National Weather Service Key West FL 150pm EST Wednesday Dec 31 2025 .MORNING Issued at 1055am EST Wednesday Dec 31 2025 A burst of winter is here in the Keys this morning! After yesterday morning's frontal passage, temperatures have been gradually falling into today. Currently, temperatures range from the mid 50s at the Upper Keys to near 60 in the Lower Keys. This is mostly in part to the moderate to fresh northerly breezes draining off of mainland Florida advecting cooler air into our area. Observation stations along the Reef note that winds have slackened a touch since last night's nocturnal surge, but are still blowing enough for Small Craft to Exercise Caution. Meanwhile, KBYX is free of precipitable echoes despite GOES-19 visible imagery depicting a field of stratocumulus painted over the western half of our waters. Our postfrontal pattern continues as high pressure establishes itself in the western Gulf off the coast of Texas today. As this surface high continue to shift east, our northerly breezes will gradually slacken over the next few days. That being said, another nocturnal surge will be possible early tomorrow morning especially with temperatures still leaning on the cooler side. This morning's KKEY sounding is about as dry season as it gets down here with a PW of 0.42 inches, single digit surface CAPE, backing wind profile, and a potent inversion at around 880 mb with dry modified continental air aloft. Needless to say, Probability of Precipitation are to remain near nil for the next few days. Another round of cooler temperatures is on tap for tomorrow morning with possibly some lows hitting the 45 to 50 range in the Upper Keys while the rest of the island chain claws as far down the mid 50s. Conditions will mild out moving into the weekend so enjoy it (or don't) while it lasts! Issued at 430am EST Wednesday Dec 31 2025 CIMSS products show a deep upper level trough across the eastern United States with this trough extending southward all the way to Jamaica. At the surface, high pressure remains across southeast Texas. Florida and the Keys remain on the eastern side of this expansive high. Therefore, this is promoting mainly north breezes near 20 knots at marine platforms surrounding the Island Chain. GOES 19 Total Precipitable Water (TPW) products shows vast dry air across Florida with a decent gradient in the PWAT (Precipitable Water) values across the Keys. The PWAT (Precipitable Water) values range from 0.8 inches across the Straits to around 0.4 inches across the northern areas. KBYX radar is not detecting any shower activity as a result. GOES 19 Nighttime Microphysics shows some low level cumulus clouds across the western areas of the Keys due to the cold air moving over the warm water surface. This creates some instability resulting in some cloud formation, similar to how lake-effect develops off the Great Lakes well to our north. By the time this cold air reaches the southern Gulf, it has picked up enough moisture to produce clouds. Temperatures along the Island Chain are in the lower to mid 50s for the Upper Keys and near 60 degrees for the Middle and Lower Keys. Dew points have also tumbled with 30s for the Upper Keys and mid to upper 40s for the Middle and Lower Keys. .FORECAST... In the wake of the front yesterday, breezy conditions are expected to continue early this morning. High pressure over southeast Texas this morning will continue moving to the east to southeast throughout the week while slowly weakening. Due to the slow movement of the high, the northwest to north flow will linger into New Years Day/Thursday night before breezes start to shift to the northeast. Even though breezes slacken a little bit today, a subtler wind surge is anticipated tonight into New Years Day due to the mainland nocturnal land breeze. As we approach the weekend, the high will move directly overhead which will result in a period of light to variable breezes. In addition, the coldest temperatures are expected to occur tonight just in time to ring in 2026! Overnight lows into New Years Day morning are expected to be in the upper 40s for the Upper Keys and mid to upper 50s for the Middle and Lower Keys. Temperatures will start to slowly rebound beginning Friday with highs getting back towards 70 degrees and overnight lows back into the 60s. Over the weekend, temperatures will be back to near normal which is highs in the mid 70s and overnight lows in the lower to mid 60s. Dry air will remain entrenched across the Keys through the period leading to nil rain chances through Saturday. Another potentially reinforcing/weak front may press through the Keys during the second half of the weekend into early next week. However, the timing, intensity, and if this front will even push through remains to be seen. Stay tuned! Marine Issued at 1055am EST Wednesday Dec 31 2025 No watches, warnings, or advisories are currently in effect for the coastal waters of the Florida Keys, but Small Craft Should Exercise Caution in all waters until winds decrease. From synopsis, mainly fresh northwest to north breezes will slacken slowly through the day as high pressure moves east to southeast into the eastern Gulf. Another nocturnal wind surge is expected overnight into tomorrow morning, but once the high moves overhead towards the end of the week/weekend breezes become light and variable. NOAA Key West FL Office: Watches - Warnings - Advisories FL...None. GM...None. |
Key West FL Radar
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