Flhurricane.com - Central Florida Hurricane Center - Tracking Storms since 1995Hurricanes Without the Hype! Since 1995
There is currently nothing on the horizon tropically in the Atlantic before Hurricane Season starts on June 1st.
|
Show Area Forecast Discussion - Key West, FL (Florida Keys) Selection: |
| #1181070 (Received by flhurricane at: 7:48 PM 20.May.2024) AFDKEY Area Forecast Discussion National Weather Service Key West FL 341 PM EDT Mon May 20 2024 ...New DISCUSSION, MARINE, AVIATION... .DISCUSSION... Issued at 241 PM EDT Mon May 20 2024 Water vapor imagery highlights a mid to upper-level low exiting the Atlantic Bight. Mean-layer ridging is well to our west, placing the Keys in the dry and sinking western flank of the upper trough axis. Nevertheless, isolated thunderstorms continue to capitalize on the steep mid-level lapse rates. The thunderstorm behavior has changed though. From early this morning through the early afternoon, lines of storms aligned with the mean layer shear propagated both up and down shear, leading to astronomical rainfall totals. Radar derived and gauge totals suggest maxima near 5" in Lower Matecumbe, close to 10" across portions of western Vaca Key, and 5 to 7" for areas between Big Coppitt to Sugarloaf. Everybody got more than an inch except areas east of Key Largo. It is remarkable how quickly things can change given nearly three rain-free weeks. Marathon has not measured rain since April 30th and just set its all time monthly rainfall record (7.08" as of 300 PM). .FORECAST... The upper-level trough will sharpen tonight through Wednesday with the axis dipping south across central Cuba. More or less at the same time, a mid-level vort lobe noted on water vapor imagery nearing the FL/GA line will pivot into the eastern Gulf and round into the base of the upper-level trough. Typically the back side of these anticyclonic wave breaks are dry and stable. This may not be the case through the short term. Low-level steering will remain weakly confluent and variable at times. Forecast soundings suggest lower tropospheric moisture will be adequate through 700 mb to support rain and thunder chances, and sort of an ideal scenario for a mesoscale feast of outflows and triggers. We advertise 30% chances through the short term, well above the MOS consensus. There will be a short window Wednesday night through Thursday night when drier air invades the profile before the easterlies resume. We advertise near-normal (20%) rain chances through the extended with meager low-level moisture and a rather non-descript pattern of undulation in the easterlies. Good news in the heat department, the oppressive heat/humidity of the last week will not make a return over the next week. && .MARINE... Issued at 241 PM EDT Mon May 20 2024 Thunderstorms will decrease in coverage as breezes veer to the northwest and increase. Tuesday through Wednesday, breezes will gradually shift to the east as high pressure in the western North Atlantic builds back in across the region. Gentle east to southeast breezes will resume Friday through Saturday. && .AVIATION... (18Z TAFS) Issued at 241 PM EDT Mon May 20 2024 Earlier convection that moved through both terminals has finally waned with KBYX radar showing any thunderstorm activity now well off to the south and west. With the atmosphere largely worked over for the time being, we expect the next few to several hours to largely remain quiet outside of a brief isolated shower. Therefore, expect VFR conditions to continue through the remainder of the afternoon and into the evening hours. Hi-res guidance is showing another potential round of convection overnight into Tuesday morning. However, this will largely depend on how much the atmosphere is able to destabilize after being worked over today. Due to the uncertainty, have opted to leave mention of VCSH or VCTS out of TAF for now. Winds will continue to be influenced bu the convective environment for at least the next few hours before becoming westerly to northwesterly tonight. && .CLIMATE... So far today, Marathon has recorded 7.08 inches as of the 253 pm observation. The previous record for the date was 1.68 inches set back in 1991. Rainfall records for MTH date back to 1950. && .PRELIMINARY POINT TEMPS/POPS... Key West 79 89 79 89 / 30 30 30 20 Marathon 80 89 80 89 / 30 30 30 30 && .KEY WATCHES/WARNINGS/ADVISORIES... FL...None. GM...None. && $$ |
| #1181039 (Received by flhurricane at: 3:42 PM 20.May.2024) AFDKEY Area Forecast Discussion National Weather Service Key West FL 1141 AM EDT Mon May 20 2024 ...New DISCUSSION, MARINE, AVIATION... .DISCUSSION... Issued at 1118 AM EDT Mon May 20 2024 The main stories this morning are the training thunderstorms and heavy rainfall. Before dawn the Lower Matecumbe area was the first focus, then Vaca Key near and after dawn, and now the Lower Keys. The profile sampled by the 12Z was juiced (PW ~2"), contained moderate ML instability and minimal inhibition, and EFF deep layer shear roughly oriented (WSW-ENE) parallel to a weak convergence zone, hence the heavy rainfall. Training cells have steadily back built and new updrafts have been favored on both the up and down shear vectors. The highest radar derived totals so far are 5 to 10", with some believable gauges approaching 7". Until we can get the northwest steering flow in here later this afternoon, likely more of the same for those areas that can recharge. When it rains, it pours. && .MARINE... Issued at 1118 AM EDT Mon May 20 2024 Scattered thunderstorms accompanied by heavy rainfall, frequent lightning, and small hail will persist across the coastal waters of the Florida Keys into the afternoon. By later this afternoon or this evening, thunderstorms will decrease in coverage as breezes veer to the northwest and increase. Tuesday through Wednesday, breezes will gradually shift to the east as high pressure in the western North Atlantic builds back in across the region. && .AVIATION... (15Z TAFS) Issued at 1118 AM EDT Mon May 20 2024 KBYX radar shows convection ongoing across the Middle and Lower Keys. This activity is being driven by an outflow boundary propagating slowly to the west. This activity will continue to lower CIGs to MVFR conditions with IFR possible. LIFR and IFR conditions are possible for VIS as thunderstorms continue to impact the area, especially MTH. For now, EYW remains quiet but we are watching thunderstorms off to the east that may backbuild towards the terminal over the next couple hours. Winds will be influenced by the convective environment with the strongest gusts occurring in and around thunderstorms. && .CLIMATE... So far today, Marathon has recorded 5.95 inches as of the 953 am observation. The previous record for the date was 1.68 inches set back in 1991. Rainfall records for MTH date back to 1950. && .PRELIMINARY POINT TEMPS/POPS... Key West 90 79 89 79 / 60 30 30 30 Marathon 89 80 89 80 / 60 30 30 30 && .KEY WATCHES/WARNINGS/ADVISORIES... FL...None. GM...None. && $$ |
| #1181006 (Received by flhurricane at: 8:57 AM 20.May.2024) AFDKEY Area Forecast Discussion National Weather Service Key West FL 451 AM EDT Mon May 20 2024 ...New DISCUSSION, MARINE, AVIATION... .DISCUSSION... Issued at 451 AM EDT Mon May 20 2024 This morning has felt like summertime in terms of convection across the Florida Keys. Mesoscale boundaries have been the main trigger mechanism for convection, with multiple outflow boundaries still present on radar. KBYX is currently detecting scattered convection within the forecast area, with most of the storms aligning with or being adjacent to the island chain. The strongest activity is currently located near the Upper and Middle Keys. Good upper- level support has been very evident across most of the region, with radar derived hail hedging close to 2" inches in the waters across the Bahamas and even in a storm that plowed through the distant Straits earlier. The activity closer to home has not been able to fire up as well until just recently, which may be due in part to drier air in the mid- levels sampled by last night`s 00Z sounding. The storms that have been able to overcome this drier air have been able to tap into the fat CAPE profiles and have gone nuts. Panning out from the Keys, a trough is extending across the western North Atlantic, dragging a frontal boundary in its wake. This front has made it almost to Central Florida. A good environment will remain in place for scattered showers and isolated thunderstorms today. Winds will continue to shift to the north ahead of the aforementioned frontal boundary, which will continue to usher in lower dew points. Dew points have already dropped roughly 3-5 degrees over the past few hours, which has made quite an impressive difference in the level of comfort when walking outdoors. These lowered dew points and temperatures will keep the Keys below the threshold for Heat Advisories through the remainder of the week. Winds will remain generally from the northwest to north through Tuesday night, briefing becoming variable on Tuesday. Decent moisture will remain in place through Wednesday, which could help spur on mesoscale processes such as cloud lines during this timeframe. Guidance has trended downwards on the higher rain chances through Wednesday, so have capped PoPs at 30%. Forecast rain chances may continue to decrease, depending on how much dry air can invade into the mid-levels. Easterly flow will return by mid-week as high pressure really builds back in, which will allow for dew points to gradually rise back into the mid 70s. As of now, MOS guidance does not hint at any of the oppressive dew points we have been tormented with over the past few days returning through the extended forecast luckily. && .MARINE... Issued at 451 AM EDT Mon May 20 2024 There are no watches, warnings, or advisories in effect for the Florida Keys coastal waters. From synopsis, a frontal boundary currently draped across north Central Florida has helped the wind field across the Florida Keys become somewhat nebulous this morning. Breezes have begun to shift to the west to northwest in the western waters. By this afternoon, breezes will veer to the northwest and increase. Tuesday through Wednesday, breezes will gradually shift to the east as high pressure in the western North Atlantic builds back in across the region. && .AVIATION... (06Z TAFS) Issued at 451 AM EDT Mon May 20 2024 Widely scattered showers with a few isolated thunderstorms will wax and wane in the vicinity of the island chain early this morning. After sunrise, this activity will diminish with slight rain chances persisting throughout the rest of the day. VCTS is included at both terminals until we expect this activity to die down, though any shower passing over a terminal may result in MVFR CIGs or VIS and will be TEMPO`ed as needed. Near surface winds will start out light of the southwest, becoming northwest at 5 to 10 knots this afternoon. && .CLIMATE... On this day in 1932, the daily record rainfall of 3.83" was recorded in Key West. Rainfall records date back to 1871. && .PRELIMINARY POINT TEMPS/POPS... Key West 90 79 89 79 / 20 30 30 30 Marathon 89 80 89 80 / 30 30 30 30 && .KEY WATCHES/WARNINGS/ADVISORIES... FL...None. GM...None. && $$ |
| #1180970 (Received by flhurricane at: 2:57 AM 20.May.2024) AFDKEY Area Forecast Discussion National Weather Service Key West FL 1054 PM EDT Sun May 19 2024 ...New DISCUSSION, MARINE, AVIATION... .DISCUSSION... Issued at 1054 PM EDT Sun May 19 2024 Winds are on a downward trend after a surge developed in the late afternoon and early evening hours. Winds quickly clocked around from the southwest, becoming west to northwest and reaching sustained speeds of around 15 knots. Within the last hour these winds are quickly coming down and boxing around the compass again. Convection that was out across the southeast Gulf of Mexico dissipated well before it got to our waters. Meanwhile, convection is blossoming along an outflow boundary from prior showers and thunderstorms that develop along the north coast of Cuba. These showers and thunderstorms have entered the Straits of Florida between the Marathon Humps and Cay Sal Bank. This current activity is trekking north to northeast. Going through the overnight, additional convection is possible given how many ghost boundaries are out there. Where and which ones will light up remains questionable. Hi-res CAMs suggest that an outflow boundary moving northwest from the convection centered near Cay Sal Bank will have the "best" potential of triggering new convection. It remains to be seen how far northwest it will get and if it will stall across the island chain overnight. For now will maintain 40 percent PoPs given the uncertainties listed above. Nonetheless, tonight through Tuesday morning will be the best period to see accumulating rain in the past 2 weeks. && .MARINE... Issued at 1054 PM EDT Sun May 19 2024 The western extent of a low-level ridge axis that extends west-northwest has begun to loosen its grip across the Florida Keys. At the same time a frontal boundary is sliding south across the Florida Peninsula, which has shifted breezes from the northwest. These breezes will briefly go light and variable overnight before becoming south to southwest by Monday morning. Lastly, there may be a break in the rain-free conditions tonight through Tuesday, followed by variable breezes turning to the east Wednesday through Thursday. && .AVIATION... (00Z TAFS) Issued at 1054 PM EDT Sun May 19 2024 VFR conditions will prevail for now. Watching for the potential for showers and thunderstorms to develop along remnant boundaries. Given uncertainty on the placement of individual boundaries and which boundaries will trigger convection, will at least maintain mentions of VCSH but have omitted TS for a later update. && .KEY WATCHES/WARNINGS/ADVISORIES... FL...None. GM...None. && $$ |
