


Area Forecast Discussion
Issued by NWS Newport/Morehead, NC
Issued by NWS Newport/Morehead, NC
202 FXUS62 KMHX 061130 AFDMHX Area Forecast Discussion National Weather Service Newport/Morehead City NC 730 AM EDT Sun Jul 6 2025 .SYNOPSIS... Newly named Tropical Storm Chantal will make landfall early this morning along the coast of the Carolinas bringing an increased chance of showers and thunderstorms, including the risk of locally heavy rainfall, through early next week. && .NEAR TERM /THROUGH TONIGHT/... As of 3 AM Sun... Key Messages: - Shower and thunderstorm threat continues through the day as Chantal nears the coast of the Carolinas. - Torrential rainfall and flash flooding remain the main risk, but an isolated tornado remains possible especially through midday. Dominant weather maker across the Carolinas remains Tropical Storm Chantal, currently 75 miles east-northeast of Charleston SC and continuing to drift northward at near 10 mph. The outer rain bands of the cyclone continue to quickly race across eastern NC, bringing periods of brief but torrential rainfall as PWATs surge north of 2-2.25". CAMs show good continuity in the forecast this morning, showing bands continuing to cross the FA in waves as the cyclone eventually makes landfall in extreme northeastern SC in the next hour or so. The primary threat from this system remains heavy rain through this morning and into the afternoon given forecast PWATs staying above 2" through the period. With a modest increase in instability this afternoon as highs climb into the upper 80s, more organized convection are favored to be highly efficient rainfall makers and produce a quick 1-2 inches of rainfall. HREF LPMM guidance suggests in a worst case scenario, amounts in excess of 4" are possible. Given the flash flood risk posed by the rainfall, WPC has left all of the area in a Marginal Risk of excessive rain. In addition to rain, there is also a low tornado threat as is to be expected on the northeastern quadrant of a TC. The most favorable window for tornadic activity is now through around midday as 0-1km SRH peaks at around 100-150 m2/s2. Locations most favored are south of Highway 264 and west of Highway 17, closest to the core of Chantal. All of the FA is at some risk, however, as rainbands displaced from the TC have already shown a history of brief spin-ups in the past couple of hours. Rainfall activity becomes more scattered in the afternoon as TC Chantal gradually loses tropical characteristics and a dry slot noses into the FA. Where sun peaks through, highs are likely to reach into the mid to upper 80s. && .SHORT TERM /MONDAY THROUGH 6 AM MONDAY/... As of 315 AM Sun... Key Messages: - Isolated showers and storms inland, and scattered to numerous along and just offshore will continue to pose a risk of flash flooding threat overnight. - Tornado risk wanes through the nighttime hours. Core of Chantal will likely be lifting across central NC by evening and through the overnight hours. Expanding dry slot suggests a mostly dry evening across the coastal plain with only isolated showers or stray thunderstorm, but with PWATs still near 2" heavy rainfall remains a threat. Along the sounds and coastal waters, nocturnal maximum of convection is likely to rapidly blossom. Any robust activity that makes it onshore could add another 1-2" (locally higher) onto daytime totals, enhancing the flash flood risk. Tornado threat will be waning overnight as core of highest SRH is displaced to our north and west. Expansive cloud cover keeps lows a couple degrees warmer, in the mid 70s to near 80 along the coast. && .LONG TERM /MONDAY THROUGH SATURDAY/... As of 315 AM Sun... Key Messages - Multiple rounds of moderate to heavy rainfall possible this week TS Chantal will weaken across the NC coastal plain Monday and slowly lift northward Monday night and Tuesday. Periods of heavy rainfall will continue to be possible on Monday with PW values around 2" or greater. Weak ridging builds across the area Monday night and Tuesday but could see isolated to scattered showers bringing locally heavy rainfall. A series of shortwave trough will push across the region mid to late week continuing to bring an unsettled weather across the region. With high PW values, the greatest threat from the storms will be heavy rainfall. At this time, instability and shear parameters do not look overly impressive for severe storms to develop but could see a few storms producing strong wind gusts. The warmest temps of the long term look to be Tuesday and Wednesday with highs in the low 90s inland from the coast and heat index values around 100-105, otherwise temps expected to be near or a couple of degrees below climo. && .AVIATION /12Z SUNDAY THROUGH THURSDAY/... SHORT TERM /through 12z Mon/... As of 730 AM Sun...TC Chantel moved inland a few hours ago, now sitting over the NC/SC border. Mix of rain bands and scattered showers continue to migrate from south to north across area terminals. Cigs have bounced around considerably since 06z but trend is more predominant MVFR across the south while VFR prevails farther north. As rainbands traverse terminals, expect temporary drops to IFR in torrential rainfall and occasionally gusty cells gusting up to 30 kt at times. As Chantal lifts north, expecting a dry slot to work in across eastern NC bringing a likely lull in precip starting from 16z onward, especially across the coastal plain with precip activity becoming much more isolated. This should also help scatter out cigs and bring a brief return to VFR for the afternoon. After sunset, TAF forecast closely follows the LAMP showing cigs descending back to MVFR as mixing layer lowers. However, given LAMPs recent trends to bring sub-VFR cigs in too fast, this portion of the forecast is of lower than usual confidence. In addition to showers, winds will be gusting up to 20 kt inland and 25 kt across OBX in association with the gradient associated with the TC. LONG TERM /Monday through Thursday/... As of 325 AM Sun...TS Chantal will lift into the coastal plain and gradually dissipate as it slowly lifts northward bringing periods of showers and thunderstorms bringing sub-VFR flight cats. A series of mid- level systems will push across the region mid to late week continuing to bring the threat of showers and storms with reduced flight cats. Late night and early morning fog and stratus will also be possible most mornings. && .MARINE... As of 4 PM Saturday... SHORT TERM /through Sunday/... As of 325 AM Sun...TC Chantal continues to drift northward towards the coast of the Carolinas this morning with rainbands quickly progressing across area waters from south to north. Regional observations show east to southeasterly winds ranging from 10-20 kt and seas ranging from 3-5 feet north of Cape Lookout to 8-10 feet across the outer portions of Onslow Bay. Dangerous boating conditions are expected to prevail through the day as swell from the TC continues to bleed northward, impacting primarily Onslow and Raleigh Bay but seas reaching up to 6 feet north of Oregon Inlet. The wind field associated with Chantal will expand through tonight as it decays inland, and this required further expansion of existing SCAs into the Croatan and Roanoke sounds, as well as the waters north of Oregon Inlet. All SCAs, with the exception of the far northern waters, are in effect for all of Sunday. Peak winds across area waters reach to around 25 kt through today. LONG TERM /Tuesday through Thursday/... As of 330 AM Sun...High pressure remains centered over the western Atlantic next week with a series of systems pushing across the area. This will keep gradients somewhat pinched with SW winds around 10-20 kt and seas around 2-4 ft currently forecast during the long term period. However, some guidance is suggesting low end SCA could occur at times during the middle of next week, especially in gusts. && .HYDROLOGY... As of 335 AM Sun...Bands of heavy rain and thunderstorms already brought 2-3 inches of rainfall to portions of ENC yesterday as the outer bands of TS Chantal tracked across the region. Latest forecast calls for additional rounds of heavy rain and thunderstorm activity through today as TS Chantal makes it closest point of approach to ENC this morning into the afternoon. Latest guidance suggests and additional 1-2 inches of rain with localized amounts in excess of 3 inches will be possible across portions of ENC this morning and afternoon, bringing at least a low end flash flooding threat which would be maximized in our more urban areas, as well as locales that saw the heaviest rainfall yesterday. We will also have to watch areas along the sounds and Atlantic overnight as offshore precipitation increases in coverage. Although most activity will remain over the ocean, any cells that drift onshore could also dump an additional inch or two of rainfall. Expect the rainfall and flooding threat to gradually lower on Monday through the day as the last of the tropical moisture from Chantal makes its way to the north and east away from ENC. && .MHX WATCHES/WARNINGS/ADVISORIES... NC...Beach Hazards Statement through this evening for NCZ195-196- 199-203>205. MARINE...Small Craft Advisory until 11 PM EDT Monday for AMZ135-231. Small Craft Advisory from 2 PM this afternoon to 11 PM EDT this evening for AMZ150. Small Craft Advisory from noon today to 6 PM EDT Monday for AMZ152. Small Craft Advisory until 6 PM EDT Monday for AMZ154. Small Craft Advisory until noon EDT Monday for AMZ156-158. && $$ SYNOPSIS...MHX NEAR TERM...MS SHORT TERM...MS LONG TERM...CEB AVIATION...MS/CEB MARINE...MS/CEB HYDROLOGY...MHX