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![\"Hawaii](\"https:\/\/ialert.com\/blog\/wp-content\/uploads\/2026\/08\/ialert-hawaii-tropical-storm-ptc-one-c-august-13-2026.jpg\")
\n for Potential Tropical Cyclone One-C, valid 12:00 UTC August 13, 2026 (2 a.m. HST). The track carries the center from east-southeast
\n of the Big Island on Thursday to near or over the islands from Friday night through Sunday. The cone shows the likely range of the
\n center, not the extent of impacts, which reach well outside it. Source: NOAA Central Pacific Hurricane Center.<\/figcaption><\/figure>\n
A Hawaii tropical storm<\/strong> threat is now forecast to reach the islands late Friday. The NOAA Central Pacific The Central Pacific Hurricane Center’s own headline on the advisory is blunt: the system is forecast to bring heavy rainfall, high Key points:<\/strong><\/p>\n Get Lightning Detection Alerts for Your Location<\/p>\n When dangerous lightning is detected near your area, iAlert sends you an immediate notification by email, text message, or phone call, so you know when to seek shelter and when it is safe to head back outside.<\/p>\n Sign Up for Lightning Detection Alerts →<\/a>\n<\/div>\n At 11 p.m. HST Wednesday (0900 UTC Thursday), the disturbance was centered near latitude 14.8 North, longitude 144.5 West. That put By the 2 a.m. HST Thursday outlook the center of the developing Hawaii tropical storm had closed to about 750 miles east-southeast One detail matters more than the center position for anyone planning around this Hawaii tropical storm: tropical-storm-force winds The designation is often misread. A Potential Tropical Cyclone is a disturbance that is not yet<\/em> a tropical cyclone but In this case the disturbance already has 40 mph winds, but forecasters noted it still lacks the organized shower and thunderstorm That is a distinction of classification, not of consequence. The rainfall and surf forecasts do not wait for the naming.<\/p>\n Rainfall is the headline hazard of this Hawaii tropical storm.<\/strong> The Central Pacific Hurricane Center forecasts 5 to Timing for the Hawaii tropical storm runs west across the chain. Heavy rain begins on the Big Island Friday, then spreads westward Surf is the second Hawaii tropical storm hazard.<\/strong> Swells generated by the system are expected to reach east-facing Wind is the third.<\/strong> The advisory states there is an increasing risk of wind impacts in the Hawaiian Islands A large high pressure system north of the Hawaiian Islands is the steering feature here. It should push the disturbance generally Confidence in that track is lower than usual, and forecasters said so plainly. The guidance shifted somewhat south of the previous Intensity has a genuine tug-of-war in it. The environment over the next two days favors strengthening, but the system’s broad There is a caveat worth holding onto: if the system tracks farther south of Hawaii than forecast, it stays in more favorable For residents, the practical read on this Hawaii tropical storm is that the rainfall and surf forecasts are far more reliable right Because heavy rain and flooding lead this Hawaii tropical storm, preparation should start with water, not wind. Know whether your Clear gutters and drains now while conditions are calm. Move vehicles off low ground. Never drive through a flooded road. More than Secure anything outdoors that wind can lift, and stock at least 72 hours of water, non-perishable food, medications and important Stay out of the ocean once east-facing Hawaii tropical storm swells build Friday. Life-threatening surf and rip currents are Late Friday. The Central Pacific Hurricane Center forecasts heavy rainfall, high winds and dangerous surf beginning across the The Big Island. Heavy rainfall is forecast to begin affecting Hawaii Island on Friday and then spread westward across Maui County, 5 to 10 inches across much of the island chain, with maximum totals of 20 inches possible. Forecasters warn this may produce Not as of the 2 a.m. HST Thursday outlook. The Central Pacific Hurricane Center said a Hurricane or Tropical Storm Watch would Not as forecast. The system is expected to become a tropical storm by Thursday night and strengthen gradually, with shear, dry air That is Tropical Storm Hernan, unrelated to the Hawaii tropical storm threat, recently upgraded and located well west of the Sources:<\/strong><\/p>\n Get Severe Weather Alerts for Your Location<\/p>\n When any NWS watch, warning, or advisory is issued for your area, iAlert Sign Up for Severe Weather Alerts →<\/a>\n <\/div>\n","protected":false},"excerpt":{"rendered":"
\n Hurricane Center is issuing advisories on Potential Tropical Cyclone One-C, which its 11 p.m. HST Wednesday bulletin placed about 775
\n miles east-southeast of Hilo with maximum sustained winds of 40 mph. The system is expected to become a tropical storm by Thursday
\n night and to strengthen as it moves west-northwestward near or over the island chain into the weekend.<\/p>\n
\n winds and dangerous surf to the Hawaiian Islands starting late Friday.<\/p>\n\n
\n inches.<\/li>\nWhere Potential Tropical Cyclone One-C Is Now<\/h2>\n
\n it about 775 miles east-southeast of Hilo and about 985 miles east-southeast of Honolulu, moving west at 10 mph with a minimum
\n central pressure of 1002 millibars.<\/p>\n
\n of Hilo. Formation chance stood at 90% through both 48 hours and 7 days, the top of the Central Pacific Hurricane Center’s “high”
\n category.<\/p>\n
\n already extend outward up to 275 miles from the center, and almost all of that is on the northeast side. A system that broad can
\n deliver impacts to an island the center never reaches.<\/p>\nWhat Is a Potential Tropical Cyclone?<\/h2>\n
\n that poses the threat of tropical storm or hurricane conditions to land areas within 48 hours. The label exists for one reason: it
\n lets forecasters issue watches and warnings before the system formally organizes, instead of waiting and losing lead time.<\/p>\n
\n activity near a defined center that would make it a tropical storm. Satellite wind data showed the strongest winds sitting roughly 200
\n miles northeast of the center rather than wrapped around it.<\/p>\nThe Hazards Behind This Hawaii Tropical Storm Threat<\/h2>\n
\n 10 inches across much of the island chain, with maximum totals of 20 inches possible. Forecasters warn this rainfall may produce
\n life-threatening flooding and mudslides, especially in areas of steep terrain, which describes most of the populated windward slopes
\n in Hawaii.<\/p>\n
\n over Maui County, Oahu and Kauai during the weekend.<\/p>\n
\n shores of the state on Friday, then spread westward and build through the weekend. Forecasters expect life-threatening surf and rip
\n current conditions.<\/p>\n
\n regardless of the exact track. That phrase is deliberate: the wind threat does not hinge on a direct hit.<\/p>\nMeteorologist’s Take on the Hawaii Tropical Storm Forecast<\/h2>\n
\n west-northwestward for the next several days, which is what carries the track toward the chain rather than harmlessly south of it.<\/p>\n
\n cycle, and the track forecast will stay low confidence until a better-defined center forms. A sprawling system can relocate its center
\n as it organizes, which shifts the whole forecast with it.<\/p>\n
\n structure means that strengthening should be gradual. As it nears Hawaii, southwesterly wind shear, dry air being drawn in, and
\n interaction with the terrain of the Big Island should slow or stop intensification.<\/p>\n
\n conditions and would likely end up stronger than currently predicted. A track error south is not automatically good news.<\/p>\n
\n now than the exact center position. Prepare for water, not for a landfall point.<\/p>\nHow to Prepare for a Hawaii Tropical Storm<\/h2>\n
\n home sits in a flood-prone area, near a stream, or below a steep slope where mudslides are a risk. Those are the areas 20 inches of
\n rain will find first.<\/p>\n
\n half of all flood drownings happen when a vehicle is driven into water, because neither the depth nor whether the roadbed is still
\n there can be judged from behind the wheel.<\/p>\n
\n documents in a waterproof container. Fill your gas tank and pick up supplies before a watch is upgraded, since those resources go
\n quickly.<\/p>\n
\n forecast, and those conditions arrive ahead of the storm itself. Monitor active
\n weather alerts<\/a> and track the latest local forecast<\/a> as the system approaches.<\/p>\nHawaii Tropical Storm FAQ<\/h2>\n
When will Hawaii tropical storm conditions begin?<\/h3>\n
\n islands starting late Friday, with the center nearing the chain by that evening. Surf on east-facing shores builds beginning
\n Friday.<\/p>\nWhich island does the Hawaii tropical storm hit first?<\/h3>\n
\n Oahu and Kauai during the weekend, following the storm’s west-northwestward motion.<\/p>\nHow much rain is forecast with this Hawaii tropical storm?<\/h3>\n
\n life-threatening flooding and mudslides, particularly in areas of steep terrain.<\/p>\nHas a tropical storm watch been issued for Hawaii?<\/h3>\n
\n likely be required for a portion of the state by early Thursday, and advised that interests throughout the Hawaiian Islands closely
\n monitor the system.<\/p>\nWill it be a hurricane when it reaches the islands?<\/h3>\n
\n and terrain interaction expected to slow or halt that strengthening near the islands. A hurricane watch was still listed as a
\n possibility, so the forecast is not settled.<\/p>\nWhat about the other system in the Pacific?<\/h3>\n
\n southern tip of the Baja California Peninsula in the eastern Pacific. It is a separate system and is not a threat to Hawaii.<\/p>\n\n
\n Cyclone One-C Public Advisory Number 4, 11:00 PM HST August 12, 2026<\/a><\/li>\n
\n Cyclone One-C Forecast Discussion Number 4<\/a><\/li>\n
\n Weather Outlook, 2:00 AM HST August 13, 2026<\/a><\/li>\n<\/ul>\n
\n sends you an immediate notification by email, text message, or phone call, 24 hours a day, 7 days a week.<\/p>\n