Area Forecast Discussion
Issued by NWS Key West, FL
Issued by NWS Key West, FL
602 FXUS62 KKEY 060946 AFDKEY Area Forecast Discussion National Weather Service Key West FL 546 AM EDT Sun Jul 6 2025 ...New DISCUSSION, MARINE, AVIATION... .DISCUSSION... Issued at 516 AM EDT Sun Jul 6 2025 Our KBYX radar had a busy start to the overnight shift late last night as a boundary collision to the south of the island chain triggered an extensive line of showers and thunderstorms. As that line started to deteriorate, new outflow boundaries caused some showers to cross over a few island communities. Automated surface observations reported a wide range of rainfall amounts from just a few hundredths of an inch up to half of an inch where the heaviest showers occurred. The cells that looked like they were the strongest remained over the water, but radar derived estimates suggest that our local marine life may have seen roughly 1 to 3 inches of rain. Almost surprisingly, virtually all of this activity has diminished, and we are only left with some ghost boundaries. CIMSS MIMIC PWAT shows values of roughly 1.5 to 2 across most of the forecast area, but there are a few pockets of values around 1.3 advecting into the area. Opted to bring PoPs down to 30 percent for today due to both the reduced moisture, and the fact that this is an environment that has been worked over to some degree. Today, ridging will gradually build in as Tropical Storm Chantal continues to lift to the north and northwest. As this occurs, breezes will slowly turn from south and southwesterly to southeasterly. While any flow with a southerly component isnt necessarily efficient with respect to moisture advection, dew points during the day will likely be in the upper 70s again, making for a sticky afternoon. The light to gentle nature of our breeze wont offer much relief. Over the start of the new work week, weather conditions will remain hot, but benign, as the ridge axis extends across Florida and into the Gulf. Wednesday through Friday is the timeframe that is still causing some raised eyebrows. A weak mid to upper level wave looks like itll pass across the region, and could lead to some unsettled weather. The hesitancy here stems from a lack of confidence regarding the direct impact this will have on our sensible weather. The impact will depend on the strength of the wave, how close (or far) it tracks from us, how fast (or slow) it moves, etc. For now, well continue to advertise PoPs just a little bit higher than normal while monitoring model trends, and we encourage everyone to stay tuned for updates as this forecast becomes clearer. && .MARINE... Issued at 516 AM EDT Sun Jul 6 2025 Weak ridging will gradually build across the area today, causing light to gentle breezes to back from south to southeast, and eventually assuming an easterly direction by tonight. These light to gentle easterly breezes will prevail through most of the week. Chances for showers and thunderstorms are close to normal through the start of the week, but an easterly wave may result in some unsettled weather sometime Wednesday and Thursday. && .AVIATION... (06Z TAFS) Issued at 516 AM EDT Sun Jul 6 2025 VFR conditions are expected to prevail at the terminals through the TAF period, though brief transient episodes of MVFR CIGs and visibilities are possible as sky coverage waxes and wanes. A passing shower or thunderstorm remains possible through the TAF period, but timing and coverage is too uncertain for TAF inclusion, so amendments and later routine TAFs will cover activity that does occur. Winds are expected to be from the south to southwest at 5 to 10 knots, becoming southeast to south this afternoon. Higher gusts are possible with passing showers. && .CLIMATE... On this day in 1957, the daily record warm low temperature of 86F was recorded at Marathon. This is also the warmest low temperature ever recorded at Marathon during the month of July. Temperature records for Marathon date back to 1950. && .PRELIMINARY POINT TEMPS/POPS... Key West 91 81 91 81 / 30 20 20 20 Marathon 88 82 89 81 / 30 20 20 20 && .KEY WATCHES/WARNINGS/ADVISORIES... FL...None. GM...None. && $$ Public/Marine/Fire...DP Aviation/Nowcasts....MC Data Acquisition.....MC Visit us on the web at weather.gov/key Follow us on Facebook and Twitter at: www.facebook.com/nwskeywest www.twitter.com/nwskeywest