####018003856#### FXUS63 KIWX 160439 AFDIWX Area Forecast Discussion National Weather Service Northern Indiana 1239 AM EDT Fri May 16 2025 .KEY MESSAGES... - Strong to severe storms are likely this evening into the early overnight (8 pm through 2 am EDT). All hazards possible. - Another round of showers and storms is expected late Friday afternoon into Friday evening. A few storms could become severe. - Warm temperatures through Friday will give way to cooler and drier conditions this weekend. && .DISCUSSION... Issued at 218 PM EDT Thu May 15 2025 High end severe threat (all hazards) remains in play this evening into the early overnight (8p-2a EDT) as any convection along an incoming dryline will have 35-40 knots of deep layer shear and 2000- 3000 j/kg of MLCAPE to work with. The low level jet also increases this evening with 0-3 km storm-related helicity pushing 250-300 m2/s2 for a tornado threat. There will also be sufficient CAPE in the hail growth zone/EML with supercells for large hail, with any organization into segments supporting a wind damage threat mid-late evening. Expectations are still for convective initiation (scattered discrete supercells) in ne IL between 21-00z, likely congealing into quasi-linear segments or clusters with eastward progression into the local area thereafter. Capping at the base of an EML, and more favorable deep ascent and low level convergence lifting through WI and MI, brings into question storm evolution/chances for areas south of the US 30 corridor. Much higher confidence in strong to severe storms breaking through the cap and tracking east through northern zones as weak height falls/cooling aloft clips the lower Great Lakes. Drier air briefly filters in behind the front later tonight into most of the day Friday with highs once again well into the 80s. Moisture does return northward late Friday into Friday evening in advance of a secondary cold front and mid level shortwave (70-80 kt 500 mb jet) arriving from the Mid MS Valley. This should be enough to generate a round of showers and storms mainly Friday evening with deep forcing, moisture quality, and deep layer shear magnitudes favorable for scattered strong to severe storms. Instability magnitudes are lacking when compared to this evening however with the primary moisture/instability reservoir likely suppressed closer to the OH River. Dry air on leading edge with a sub-cloud inverted-V profile and high DCAPE values may support good downdraft potential and localized wind damage if more robust cells develop, along with a hail threat given lingering steep mid level rates. Dry and cooler weather will filter in behind Friday night's wave in time for the weekend, with Saturday also breezy. Rain chances eventually return toward the middle of as the next western CONUS upper trough slows or cut-off over the Midwest. && .AVIATION /06Z TAFS THROUGH 06Z SATURDAY/... Issued at 1228 AM EDT Fri May 16 2025 Storms have moved east of the SBN and FWA terminals; however, convection was trying to back-build toward both sites. Believe by 06Z, storms should be far enough east that they will not be impacting the terminals so left storms out of TAFs. Winds were dropping off (diminishing) rapidly behind the storms, so diminishing winds are reflected in the TAFs and also supported by the latest (01Z) HRRR run. There is a similar setup Friday with storms once again firing late in the afternoon and evening, so have another round of storms mentioned in the TAFs. && .IWX WATCHES/WARNINGS/ADVISORIES... IN...None. OH...None. MI...None. MARINE...None. && $$ DISCUSSION...Steinwedel AVIATION...Skipper ####018002772#### FXUS62 KMFL 160442 AFDMFL Area Forecast Discussion National Weather Service Miami FL 1242 AM EDT Fri May 16 2025 ...New AVIATION... .SHORT TERM... (This afternoon through Friday) Issued at 1126 AM EDT Thu May 15 2025 To wrap up the week, an upper-level ridge continues build and push it's way further eastward into the Gulf. Meanwhile, at the surface, a body of high pressure parks over the Florida Peninsula. With deep layer dry air and the building ridge, warm and benign conditions will remain in South Florida through the remainder of the week. Temperatures will continue on an upward trend with highs reaching the low-to-mid 90s across the interior and upper 80s along the coasts this afternoon and Friday. Overnight lows will remain in the 70s along the coasts with slightly cooler conditions in the interior falling into the mid-60s. && .LONG TERM... (Friday night through next Wednesday) Issued at 348 PM EDT Thu May 15 2025 Surface high and ridging will persist over the Florida peninsula through the extended period. As a result, dry conditions and a warming trend will continue through the weekend and early next week. High temperatures will climb to the mid-upper 90s across southwest Florida, where heat indices could reach 103-105 degrees each afternoon. Meanwhile, overnight lows will drop to the upper 60s. Along coastal areas, seabreezes will help temper conditions during the daytime, keeping highs in the upper 80s and lower 90s. Overnight lows will remain balmy in the mid- upper 70s. && .AVIATION... (06Z TAFS) Issued at 1241 AM EDT Fri May 16 2025 VFR conditions prevail through the period with no weather concerns. Light/variable flow overnight becomes southeasterly by late morning Friday. && .MARINE... Issued at 1126 AM EDT Thu May 15 2025 Light winds and low seas will prevail for the next several days as the calm center of high pressure sits overhead. && .PRELIMINARY POINT TEMPS/POPS... Miami 75 90 76 89 / 0 10 0 0 West Kendall 73 92 73 92 / 0 10 0 0 Opa-Locka 75 92 75 92 / 0 10 0 0 Homestead 75 90 75 89 / 0 10 0 0 Fort Lauderdale 75 89 75 88 / 0 10 0 0 N Ft Lauderdale 75 89 75 89 / 0 10 0 0 Pembroke Pines 77 94 78 94 / 0 10 0 0 West Palm Beach 73 92 74 90 / 0 0 0 10 Boca Raton 74 92 75 91 / 0 0 0 10 Naples 74 89 74 90 / 0 0 0 0 && .MFL WATCHES/WARNINGS/ADVISORIES... FL...None. AM...None. GM...None. && $$ SHORT TERM...Rizzuto LONG TERM....ATV AVIATION...Rizzuto ####018004878#### FXUS64 KLIX 160444 AFDLIX Area Forecast Discussion National Weather Service New Orleans LA 1144 PM CDT Thu May 15 2025 ...New AVIATION... .SHORT TERM... (This evening through Saturday night) Issued at 231 PM CDT Thu May 15 2025 The main change in thinking from yesterday is the removal of any convective risk for Saturday. Although a frontal boundary is still expected to drift toward the region, it now looks like the front will stall and dissipate well north of the area. With the low level forcing mechanism stalled to the north, and a strong mid- level capping inversion in place, any development will be very isolated. Probability of convective development is at most around 10 percent Saturday afternoon, and thus is not included in the forecast package. However, if a storm does punch through the capping inversion, it could produce some gusty winds. The end result will be continued warm and muggy conditions through Saturday night. Highs will rise into the upper 80s and lower 90s each day with the warmest readings further inland away from any coastal influences. Dewpoints will be in the low to mid 70s, and overnight lows will dip toward those dewpoints each night. Additionally, skies will turn mostly cloudy each night as the elevated inversion strengthens with the cooling overnight lows. These clouds will generally start forming after midnight and scatter out to a mostly sunny sky by the late morning hours. && .LONG TERM... (Sunday through Wednesday night) Issued at 231 PM CDT Thu May 15 2025 Sunday through Tuesday will be a persistence forecast as deep layer ridging dominates the Gulf South. Deep layer subsidence will keep temperatures warmer than average with highs climbing into the upper 80s and lower 90s each day and lows only dipping into the low to mid 70s. This subsidence and warming aloft will also keep the strong mid-level capping inversion in place, and this will keep convective chances near zero through Tuesday afternoon. The overnight cloud development will continue to occur as the inversion strengthens each night, but mostly sunny conditions will be the rule by the late morning and afternoon hours each day. Wednesday will see a slight change in the pattern take hold as a potent northern stream trough axis and associated cold front sweep through the Lower Mississippi Valley. This fast moving feature will break down the persistent ridge and allow for the mid-level capping inversion to weaken. The combination of increased deep layer forcing, more favorable mid-level lapse rates, and ample warmth and available moisture will support the development of scattered convection during the day on Wednesday. At this time, the convection looks to remain below severe limits with some locally gusty winds and brief heavy downpours being the main threats. Temperatures will remain above average in advance of the front with highs warming back into the upper 80s and lower 90s. However, in the wake of the front Wednesday night, slightly cooler and drier will advect into the region allowing lows to dip into the 60s. && .AVIATION... (06Z TAFS) Issued at 1137 PM CDT Thu May 15 2025 Cooling overnight temperatures and associated temperature inversion are bringing a low stratus deck into the area. Beginning about 06Z, ceilings will be in the MVFR range from 1000 to 2000 feet. These conditions will last through 14 to 15Z before the clouds begin to lift out and conditions improve to VFR. There is also a likelihood of light fog at MCB and HUM, but visibilities will remain greater than 4SM so impacts are expected to be negligible. /Schlotz/ && .MARINE... Issued at 231 PM CDT Thu May 15 2025 A gradually weakening pressure gradient across the coastal waters will keep winds slightly lower tonight than those observed last night. As a result, no small craft advisories are in place, but small craft exercise caution wording will be added to the forecast for the waters west of Port Fourchon. This will be the final night of stronger winds as the surface high over the eastern Gulf turns more dominant this weekend into early next week. The end result will be a persistent southerly flow of 10 to 15 knots from tomorrow through early next week. && .PRELIMINARY POINT TEMPS/POPS... MCB 72 92 73 92 / 0 0 0 10 BTR 74 91 75 92 / 0 0 0 10 ASD 73 90 74 91 / 0 0 0 0 MSY 75 89 75 90 / 0 0 0 0 GPT 74 85 75 86 / 0 0 0 0 PQL 73 85 74 86 / 0 0 0 0 && .LIX WATCHES/WARNINGS/ADVISORIES... LA...None. GM...None. MS...None. GM...None. && $$ SHORT TERM...PG LONG TERM....PG AVIATION...DS MARINE...PG