####018008163#### FXUS62 KJAX 182355 AFDJAX Area Forecast Discussion National Weather Service Jacksonville FL 755 PM EDT Sat Jul 18 2026 .KEY MESSAGES... For the latest NE FL and SE GA Daily Key Messages please visit: https:/www.weather.gov/media/jax/briefings/nws-jax-briefing.pdf - Daily Afternoon & Evening Thunderstorms. Today: Drier with Best Storm Chances West of Highway 301. Sunday Tuesday: Increased Rain Chances, especially the I-75 Corridor - Medium Chance (50%) of Tropical Development over NE Gulf of America - Moderate Rip Current Risk through the Weekend - Heat Advisory Conditions Possible Towards the Middle of Next Week && .NEAR TERM /THROUGH SUNDAY/... Main Highlights This afternoon and Tonight: - Seasonably Hot and Humid Summertime Weather Continues. - Scattered thunderstorms with isolated strong storms possible for Suwannee River Valley and inland Southeast GA. Low level steering flow will trend southerly and then southwesterly through the afternoon as the Bermuda high extends an axis across southern FL and the mid/upper low off the west coast of FL migrates north-northwestward. Generally southerly flow will keep the Atlantic sea breeze from pushing as far inland this afternoon. Overall, convective coverage will be limited across most of NE FL this afternoon into evening as a dry pocket of air (PWATs 1.5-1.7 in) wraps around the base of the upper low and advects northward into NE FL generally east of I-75 and up to the SE GA coast. Though the dry pocket will curtail instability, there should be sufficient moisture (PWATs ~2 in) across interior areas of SE GA and the northern tier of the Suwannee River valley to support scattered thunderstorm development this afternoon into evening. A few showers and possibly an isolated thunderstorm may develop this evening along outflow produced by convection across central FL into the north-central FL zones. A few showers may linger over the Altamaha/Ocmulgee river basins tonight as some shortwave energy associated with the upper low rotate through southern GA. With the Atlantic sea breeze being pinned, temperatures will be hotter for communities closer to the coast today with highs into the mid 90s. The beaches should still feel the cooling sea breeze, limiting highs to the low 90s. Heat index values will generally peak in the 100-107 degree range once again. Overnight lows will be in the 70s. Additionally, satellite images and surface observations indicate that a broad surface low is forming in the northeastern Gulf beneath the mid/upper low. This low remains a potential candidate for tropical/subtropical development with a 30% chance of developing in the next 48 hours. Please continue to monitor for updates on this system. && .SHORT TERM /SUNDAY NIGHT THROUGH MONDAY NIGHT/... Main Highlights This Period: - Bouts of Showers and Storms & Heavy Rainfall, Especially for Western Areas The main focus for the forecast period continues to be the evolution and movement of an upper level low currently located over the eastern Gulf, in which the National Hurricane Center (NHC) currently gives a 20% chance of developing tropical characteristics through Monday. Model guidance has mostly continued to trend further north and west with the movement of the disturbance regardless of development, resulting the the highest forecast rainfall totals and therefore more elevated concerns for localized flooding to be areas furthest west, such as near and west of the I-75 corridor and the Upper Suwannee River Valley, with more of an influence of drier air closer to the east coast. Still expecting enough of a sea breeze influence and just high enough layer moisture for chances for convection further east, however the heaviest rainfall potential and highest coverage is expected to be over western areas each day, especially as the east coast sea breeze makes progress inland. High temperature variance will be a bit different than usual with the system skirting the area, as highs will be mainly in the low 90s with some mid 90s likely over inland north/central FL and southeast GA. && .LONG TERM /TUESDAY THROUGH SATURDAY/... Main Highlights This Period: - Scattered to Numerous Afternoon Thunderstorms - Potential heat advisory conditions by the middle of next week The upper level disturbance in the Gulf is expected to weaken while drifting northwestward Tuesday and into mid week, with low to mid level ridging building over the FL peninsula by Wednesday. A frontal boundary is forecast to drop southward towards the area Wednesday Night and Thursday before likely slowing an stalling, bringing plenty of moisture with it and therefore more numerous convective chances for much of the long term period. Temperatures overall trend near to slightly above normal for Tuesday - Friday. && .AVIATION /00Z SUNDAY THROUGH 00Z MONDAY/... Lower chances for showers tonight for TAF sites due to drier air, with a possibility of light showers passing over SGJ prior to 03z. Mild winds will be in place overnight and building in from out of the south and southeast by around 14z-16z with a potential for convection reaching sites near the end of the forecast period on Sunday by around 20z-22z. && .MARINE... Bermuda high pressure will extend a ridge axis across southern Florida today, shifting winds southerly across the local waters today. As winds shift they will strengthen to Exercise Caution levels between a trough over the southeastern US and the ridge axis to the south. Drier air moving into the coastal waters will limit thunderstorm potential through the weekend and possibly into next week. There's greater uncertainty in the forecast next week regarding the potential for tropical development in the northeastern Gulf. That system is now more likely to drift northwest through the first half of next week. For the second half of next week, a prolonged offshore flow is likely to remain in place with nocturnal southerly wind surges as a cold front approaches from the northwest. Rip Currents: There will be a moderate risk for rip currents this afternoon as surf elevates to 2-3 feet and flow shifts to SSE. Surf heights will relax some Sunday but a moderate risk is still expected during the afternoon. && .FIRE WEATHER... An increase in moisture and southerly winds is expected over the next several days as an upper level low spins in the eastern Gulf, slowly drifting north and west through early next week. The National Hurricane Center gives this low a 20% chance of developing tropical characteristics over the next 48 hours, though impacts to our area area expected to be limited outside of bands of showers and thunderstorms affecting the area at times during daytime heating. Otherwise, the increase in flow will result in good dispersions for most, with the main exceptions being near the immediate coast and west of about I-75 in northeast FL where dispersions will be slightly lower thanks to more cloud cover. The low weakens by mid next week, with a frontal boundary dropping southward towards the region. Fog Potential and Other Remarks: Significant fog development is not expected for the next several nights. Gusty and erratic winds will be possible in and near thunderstorms, with occasional outflow boundaries capable of producing sudden wind shifts well away from ongoing convection. && .PRELIMINARY POINT TEMPS/POPS... AMG 74 94 74 93 / 30 20 10 50 SSI 79 93 80 92 / 10 10 10 40 JAX 76 94 77 93 / 10 20 10 50 SGJ 76 92 77 92 / 10 20 10 50 GNV 74 92 74 91 / 10 30 30 60 OCF 74 91 75 91 / 20 40 40 60 && .JAX WATCHES/WARNINGS/ADVISORIES... FL...None. GA...None. MARINE...None. && $$ ####018004079#### FXUS63 KIWX 182356 AFDIWX Area Forecast Discussion National Weather Service Northern Indiana 756 PM EDT Sat Jul 18 2026 .KEY MESSAGES... - Smoke from Canadian wildfires will continue to bring periods of poor air quality and reduced visibility through at least Monday. - High swim risk conditions are expected along Lake MI beaches in Berrien County, MI and La Porte County, IN this evening into late tonight. Dangerous waves and currents are expected. - Additional chances for showers and thunderstorms return Monday night into Tuesday. && .DISCUSSION... Issued at 1241 PM EDT Sat Jul 18 2026 Main focus of forecast remains on arrival of a cold front, set to bring a round of strong to severe storms this afternoon and early evening. In the wake of the front, northerly winds which will bring cooler and less humid air as well a High swim risk for the SE Lake Michigan beaches. Initiation has occurred a few hours ahead of schedule with a broken line of non-severe showers and storms from Cass county, MI west to Chicago. SPC recently issued a mesoscale discussion highlighting the concerns and trends for the next several hours. To sum it up, sufficient instability (over 2000 J/KG of SBCAPE and a narrow band of around 1000 J/KG of DCAPE) is already in place to allow continued organization over the next several hours as they move SSE with primarily a damaging wind threat with the stronger storms. Sufficient low and mid level lapse rates will allow for hail production, but freezing levels AOA 15,000 ft may lead to increased wet microburst potential with embedded smaller hail. Movement will be somewhat faster than yesterday, but PWATs above 1.75" will allow for some isolated hydro concerns, especially in isolated areas that received 2 to 7 inches of rain over the past 24 hours. Maintaining a period of high likely pops along and ahead of the front. The front will clear the area this evening with increasing NW winds to bring a peak to dangerous swim conditions for all beaches along SE Lake Michigan. Beach Hazard Statements remain in effect into Sunday. Winds will shift more NE with time and slowly reduce the risk Sunday night. Cooler and slightly less humid conditions arrive behind the front as the heat dome shifts west and we end up in a NW flow aloft which persists through the remainder of the period. As is often the case with these NW flow setups, one or more convective complexes are likely to develop upstream and may move across portions of the region. The main potential right now look to reside with a stronger trough arriving later Monday into Tuesday which will likely bring some showers and storms and maybe a risk of severe weather, depending on the timing of the feature. && .AVIATION /00Z TAFS THROUGH 00Z MONDAY/... Issued at 752 PM EDT Sat Jul 18 2026 Predominantly VFR conditions outside of HZ/FU from Wildfires filtering back in. Uncertain as to how low the visibility will drop later at night, guidance suggests an initial drop to 4-6SM (currently happening at KSBN) and then improvement back to 6SM or greater later tonight. Expect KFWA to drop to 5-6SM at some point (closer to 3z), based on the immediate upstream obs from the N-NW. Otherwise, decreasing lower-mid level cloud cover tonight, then high clouds return later on (SCT-BKN). && .IWX WATCHES/WARNINGS/ADVISORIES... IN...Air Quality Alert until midnight EDT /11 PM CDT/ Sunday night for INZ005>009-012>015-017-018-020-022>027-032>034-103- 104-116-203-204-216. Beach Hazards Statement until 4 AM CDT Sunday for INZ103. OH...None. MI...Air Quality Alert from midnight tonight to midnight EDT Sunday night for MIZ078>081-177-277. Beach Hazards Statement until 5 AM EDT Sunday for MIZ177-277. MARINE...Small Craft Advisory until 5 AM EDT Sunday for LMZ043-046. && $$ DISCUSSION...Fisher AVIATION...MCD ####018009509#### FXUS63 KDMX 182356 AFDDMX Area Forecast Discussion National Weather Service Des Moines IA 656 PM CDT Sat Jul 18 2026 ...Updated for the 00z Aviation Discussion... .KEY MESSAGES... - Hot and humid through the rest of the weekend, with heat peaking on Monday. - Scattered thunderstorms across south central to southern Iowa this afternoon and evening. The severe potential is low, though an isolated severe storm cannot be ruled out in SE Iowa. - More widespread thunderstorms are expected into Monday morning, and again into late Monday afternoon through the evening. Strong to severe storms are possible. && .SHORT TERM /THROUGH MONDAY/... Issued at 243 PM CDT Sat Jul 18 2026 A look at surface features today shows an area of low pressure over the northeastern CONUS, while an area of weaker high pressure sits over the Northern Plains. Over Iowa, a boundary is draped generally from west to east across central Iowa, near the I-80 corridor, which did produce weak showers and storms through about mid-morning over northern to northeastern Iowa before tapering off. Much of northeastern Iowa received around a quarter to half inch of rain, with localized three-quarter inch values from this earlier activity. Thanks to this passing boundary to the north, temperatures so far are slightly cooler with values in the low to mid 80s, which may only increase a few more degrees this afternoon yet. Ahead of the boundary, temperatures are still expected to warm up to similar values as have been observed the last several days, with highs in the low to mid 90s. This boundary will also be the focus for the expected development of showers and thunderstorms into the late afternoon through the evening. Moisture convergence along the boundary will aid to lift parcels through a favorable environment characterized by instability values around 2500-3000 J/kg, though weak shear values around 10-15 knots and poor lapse rates will largely be working against storms from becoming strong/severe. There is a low possibility that a storm could produce a sub-severe and possible isolated severe gust over southeast Iowa where DCAPE values over 1000 J/kg are noted. Besides the potential for wind, efficient rainfall is possible during the extent of storms as they go up and quickly come down, given PWATS around 2 inches and warm cloud depths over 15 kts that could lead to rainfall amounts up to an inch or slightly higher. Outside of localized heavy rainfall with this activity, flooding is not a concern at this time. While the aforementioned area of low pressure departs further east late tonight, the surface high will pass southeast into the Great Lakes, with the boundary moving into northern Missouri. A gradual decrease in instability and continued weak flow will lead to the waning of storm development and the overall return of dry conditions across the state. Overnight conditions will feature more comfortable temperatures in the 60s, paired with mostly clear skies. Cannot rule out localized patchy fog in low lying areas through sunrise. As the previously mentioned area of high pressure tracks southeast across the Midwest, the area of subsidence associated with it will cover the greater majority of Iowa, keeping much of the area dry with light southeast winds as highs reach into the upper 80s to low 90s, with similar heat indices given slightly lower dewpoints than yesterday in the mid to upper 60s. Wildfire smoke that has impacted areas further north and east of Iowa over the past several days will make it's way into portions of eastern Iowa through the day due to this shift in winds, before decreasing into Monday. However, the thicker smoke should generally remain east of the forecast area. Over southwestern Iowa, a lingering boundary and instability axis is indicated to be overhead, which could result in some development of isolated showers and storms into the afternoon to early evening timeframe, though the bulk of activity looks to generally occur over Missouri. Into the start of the upcoming work week, a rather potent shortwave trough over Alberta/Saskatchewan Canada is progged to gradually shift southeastward across the Upper Midwest through Monday, which will shove the ridge westward of Iowa and therefore place the Central Plains into an upper level northwest flow regime. At this same time, low level west/southwest flow will increase into the area, resulting in the advection of warmer and more humid air into Iowa. In the morning, a boundary is expected to pass east/southeastward across Minnesota and into Wisconsin, where a decaying MCS is indicated to gradually track. There is a potential that this system passes through some portion of northern and northeast portion of Iowa during this period, with the main concern being damaging wind gusts as storms organize into a bowing segment, though small hail cannot be ruled out given the elevated nature of these storms. There is still uncertainty on the exact track of this system, so will have to keep an eye on later model runs and adjust per latest trends. Dry conditions are expected to return later in the morning through the afternoon, with the push of warmer and more humid air into Iowa leading to the hottest day in the forecast as highs are expected to push through the mid to upper 90s and dewpoints surge into the low to mid 70s across the forecast area. These conditions will result in widespread heat index values over 100 degrees, with heat headlines likely issued later this weekend as confidence continues to grow, so stay tuned. Those spending time outdoors should take frequent breaks in the shade and stay hydrated. && .LONG TERM /MONDAY NIGHT THROUGH SATURDAY/... Issued at 243 PM CDT Sat Jul 18 2026 As the deepening shortwave arrives into the Upper Midwest into Monday evening, a cold front is expected to push into northern Iowa and gradually track southeast over the state. Stronger forcing for ascent and moisture availability will be present overhead, paired with aforementioned hot and humid conditions. This environment will feature high instability values over 4000+ J/kg and strong shear values over 50 knots, which will be more than favorable to produce organized convection capable of becoming strong to severe, where all hazards would be in play. As storms evolve into late Monday to early Tuesday morning, the development of another MCS is indicated that looks per model guidance to move across northern into eastern Iowa, with additional concerns for potential severe winds and heavy rainfall given very favorable PWATS around 2+ inches and warm cloud depths around 16 kft. More specific details will become more clear in the coming days, but planning for potential severe weather can start now by monitoring the forecast, having multiple ways to receive warnings, and altering plans as needed. Showers and storms are expected to taper off after sunrise Tuesday, with surface winds shifting northwest as the mid-level trough and associated deepening low pressure system departs the region. A tightened pressure gradient on the backside of this system will bring breezy conditions through the day, with gusts up to 20-30 mph. Highs as a result will also be ''cooler'' with values in the 80s, and dewpoints in the upper 50s to low 60s. The pattern through midweek generally remains the same as the ridge remains west of the region and upper level northwest flow continues to bring slightly cooler and less humid conditions overhead, as highs generally top out in the 80s and dewpoints reach into the upper 50s to low 60s. Subtle waves riding the larger scale flow with periods of some level of moisture return though could bring additional chances of showers and possible storms to Iowa later Wednesday through Friday, though details are not as clear on exact timing and coverage details of this activity and will be refined in the coming days. More summer like conditions are expected to return near the end of the work week as temperatures gradually return into at least the low 90s as the ridge strengthens once again. && .AVIATION /00Z TAFS THROUGH 00Z MONDAY/... Issued at 643 PM CDT Sat Jul 18 2026 Few storms are ongoing across portions of southern Iowa but activity will start to wane after sunset. Main terminal impacted is KOTM, with a brief drop in visibility possible over the next hour or so. Then, VFR conditions largely expected to continue through the rest of the TAF period. Main exception to this would be wildfire smoke that starts to move into portions of eastern Iowa into Sunday afternoon. Confidence in impacts at the surface is not high enough to drop visibility/add a FU (smoke) addition to KALO/KOTM, but will continue to monitor trends and may include in future issuances if confidence in impacts increase. Winds out of the north to northeast this evening become light and variable overnight before settling out of the east to southeast on Sunday. && .DMX WATCHES/WARNINGS/ADVISORIES... None. && $$ SHORT TERM...Bury LONG TERM...Bury AVIATION...05 ####018006083#### FXUS61 KBGM 182358 AFDBGM Area Forecast Discussion National Weather Service Binghamton NY 758 PM EDT Sat Jul 18 2026 .WHAT HAS CHANGED... The severe thunderstorm watch has been cancelled. The severe threat has ended from this event. A few heavier rain showers and rumbles of thunder will still be possible into the evening hours. && .KEY MESSAGES... 1) Smoke across the region today gets swept out of the area tonight. 2) There is an Enhanced Risk (level 3 of 5) for severe thunderstorms with damaging winds, hail and isolated tornadoes this afternoon and early evening across the entire forecast area. 3) Pleasant, dry and mostly sunny weather looks to return for Sunday and Monday across the area. Cool and refreshing overnight lows. 4) Shower and thunderstorm chances increase Tuesday and Wednesday as the next frontal system pushes east into Central NY and Northeast PA. && .DISCUSSION... KEY MESSAGE 1... Latest runs of the HRRR model smoke guidance show high concentrations of near-surface smoke currently in place. Smoke appears as though it will linger well into the afternoon hours before a cold front sweeps through the region this evening into tonight. Disruption of the airmass due to showers and frontal passages should keep the smoke a little thinner than previous days. Air Quality Alerts remain in effect for Central NY through this evening. KEY MESSAGE 2... The initial warm front has pushed through the area this morning and early afternoon with the first round of showers and elevated thunderstorms. Partial clearing will now take place into the afternoon hours, along with dew points surging into the lower or mid 70s and temperatures reaching the upper 70s and 80s for highs. This set up will allow surface base CAPE to rise between 1500-3000 J/kg over the region, with the highest values expected over the Central Southern Tier and Wyoming Valley region by mid to late afternoon. Effective layer shear will be pushing 40-55kts over the entire forecast area by late afternoon as well, creating a favorable environment for super cell development and potential bowing segments. A corridor of DCAPE values above 800 J/kg is also expected to develop just ahead of the incoming storms, so this will set the stage for potential damaging winds and microbursts as storms strengthen. 0-1 km bulk shear is also increase, upwards of 30 kts, and SRH values are up to 300 m2/s2 along the warm front. With low LCLs between 500-750m we cannot rule out an isolated tornado or two this afternoon, either out ahead of the line of storms or embedded within any line segments as they develop and move east- southeast. The timing looks to be mainly between 2PM to 8 PM for the area, starting up across the Finger Lakes, then pushing into the I-81 Twin Tiers by late afternoon and Northeast PA/Wyoming Valley mainly 4-8 PM. SPC has maintained the Enhanced, level 3 of 5, risk across our entire forecast area today. The storms look to drop south and east, out of the area by 8-9 PM as the cold front passes through. After that, the flow turns north- northwest and a few upslope showers/clouds develop over Central NY overnight into Sunday morning. KEY MESSAGE 3... Lingering gust NW flow Sunday, between 10-20 mph may keep some stratus or strato-cu broken clouds around Sunday morning. As high pressure builds in from the west, it will become mostly sunny and pleasant Sunday afternoon. Humidity will be much lower, with dew points in the low to mid-50s and high temperatures in the upper 60s to mid 70s expected. Sunday night a 1017mb surface high moves directly overhead. This will bring clear skies, light winds and allow temperatures to drop between 45-55F overnight. Widespread valley fog is likely to form over the region as well, especially near rivers and creeks. The HRRR keeps the smoke away from our area despite the NW flow on Sunday, and the light overall flow Monday. Therefore, Monday is looking sunny and nice with low humidity and highs in the mid 70s to low 80s. Will continue to monitor the latest guidance for any changes in the smoke aloft forecasts. KEY MESSAGE 4... The next front and trough approaches the area later in the day on Tuesday, Tuesday night and into Wednesday. This will bring increasing moisture and instability in the southerly flow on Tuesday. Dew points will rise back around 70F and high temperatures are expected to reach into the lower 80s. This will all depend on the timing of the incoming front thought. SPC does have a portion of the forecast area in a 15% day 4 risk, so we will need to monitor the timing of this incoming system closely for potential organized convection. Showers and possible thunderstorms continue Tuesday night and even into Wednesday at the mid and upper level trough slowly pulls east. Conditions then look to dry out with seasonal temperatures for the end of the work week. && .AVIATION /00Z SUNDAY THROUGH THURSDAY/... Showers and isolated thunderstorms will continue to move through NEPA and CNY through the evening hours. Kept a few TEMPO groups around for the scattered coverage. Some patchy smoke is still possible as well. Still fairly good confidence that a MVFR deck forms later this evening into the overnight for all CNY terminals. This deck should burn off by mid to late morning Sunday. Outlook: The rest of Sunday and Monday...Mainly VFR. Tuesday and Wednesday...A chance of showers and thunderstorms along with associated restrictions. Thursday... Mainly VFR. && .BGM WATCHES/WARNINGS/ADVISORIES... PA...None. NY...Air Quality Alert until midnight EDT Sunday night for NYZ009- 015>018-022>025-036-037-044>046-055>057. Air Quality Alert until midnight EDT tonight for NYZ062. && $$ DISCUSSION...MJM AVIATION...MWG