Hawaii eyes unprecedented twin hurricanes

Hawaii is bracing for high surf and impacts from not one, but two hurricanes curing westward toward the Big Island.

Madeline and Lester may both make close calls to the Big Island of Hawaii in the next week. The Big Island has not recorded a hurricane landfall since records began in 1949. Some perspective here from two of the nation's premiere hurricane experts, Jeff Masters and Bob Henson from Weather Underground.

Only five tropical storms or hurricanes have made landfall on a Hawaiian island since records began in 1949, and two of those have been in the last three years (see our Monday post for details). Given Hawaii’s limited experience with tropical cyclones, both Madeline and Lester need to be taken very seriously. An unprecedented deployment of hurricane hunter resources to Hawaii kicked off on Monday afternoon, when three Air Force Hurricane Hunter aircraft were sent to the islands. Beginning on Tuesday afternoon, these aircraft will provide regular fixes every 12 hours on Madeline, and will also begin flying into Lester when it draws closer to Hawaii.

Here's the latest track on Hurricane Madeline. A close brush with the southern end of the Big Island looks likely early tomorrow.

Here's further analysis on Madeline from Weather Underground.

Madeline’s area of hurricane-force winds is quite small, only about 25 miles in radius, but tropical storm force winds (sustained winds of 39 mph or greater) extend out to 125 miles. Thus, whether or not Madeline makes landfall as a hurricane, we can expect much or most of the Big Island—and perhaps parts of neighboring islands—to experience tropical storm conditions from late Wednesday into early Thursday, with very high winds, torrential rain (up to 15” in localized parts of the Big Island, with up to 4” in Maui County), and the potential for flooding and landslides. On the Big Island, some winds could be strong enough to produce considerable damage to trees, power lines, and roofs. Surf there is expected to reach at least 15 to 25 feet on east-facing shores by Wednesday, with significant damage to roads and coastal properties possible. For more details, refer to the local statements that are compiled on a CPHC website; these will be updated as Madeline approaches.

Hurricane Lester is forecast to approach the Big Island from the east this weekend.

Here's the analysis on Lester from Weather Underground.

Lester’s current westward track is expected to bend to the west-northwest as it approaches Hawaii, which should produce a track over the weekend roughly parallel to the island chain. The official NHC outlook continues to keep Lester 100-200 miles north of the islands on Saturday and Sunday. However, there is an increased note of uncertainty in the latest (12Z Tuesday) model guidance on Lester’s track. The UKMET and the averaged GFS ensemble runs (GEFS) bring Lester across the islands over the weekend, while the Euro’s path runs just north of Oahu and Kauai. Other models keep Lester farther north by various margins. The increased spread among model solutions is a reminder that paths can change by a large amount over a 4- or 5-day period. An upper-level high to the north of Lester will become quite strong later this week, implying that a southward track closer to the islands is certainly plausible. Tropical storm-force winds are predicted to extend outwards 90 miles to the southwest of Lester this weekend, putting most of the island chain at at the edge of getting sustained 40-mph winds should Lester follow the path predicted by CPHC.

'Hermine' forming in Gulf of Mexico?

We may have Tropical Storm Hermine in the Gulf of Mexico today. Convection flared west of the developing center overnight, and I'd put the chances at 70% we'll have a tropical storm today as the system organizes further.

NOAA's national Hurricane center has upped the forecast winds to near 70 mph with Hermine as it makes a likely landfall in the Big Bend area on Florida's Gulf Coast Thursday night. 'Hermine' may then go on to strafe the Carolina Coast Saturday.

Biggest threat: Heavy rainfall

Heavy rains of 6" to 12"+ remain the biggest threat in Florida over the next 72 hours.

Threat to the east coast later?

One aspect of the storm that hasn't been discussed much; the potential for a possible east coast impact by Sunday. A few of the spaghetti models on the western end of the envelope suggest a close call for New Jersey and possibly Long Island.

NOAA's GFS model suggests a close call with the Jersey coast Sunday.

Stay tuned. It's going to get interesting in the next 48 hours.