Wednesday, August 22, 2018

Hurricane Watch For Oahu, Warning For Hawaii As Lane Hits Cat 5

From Wunderground Category 6 :

Hurricane Watch for Oahu, Hurricane Warning for Big Island as Lane Hits Category 5 Strength
Growing ever more organized on Tuesday night, Hurricane Lane reached Category 5 strength as it continued rolling toward the Hawaiian Islands. A hurricane warning was issued at 5 pm HST (11 pm EDT) Tuesday for Hawaii’s Big Island, with watches extending from Maui to Oahu, including Honolulu and the islands of Lanai, Molokai, and Kahoolawe. Watches and warnings will continue to evolve on Wednesday and beyond. Governor David Ige declared a state of emergency on Tuesday to facilitate rapid state response to the threat posed by Lane.

The NOAA/NWS Central Pacific Hurricane Center upgraded Lane to Category 5 storm in a special advisory at 6:20 pm HST Tuesday (12:20 am EDT Wednesday), with top sustained winds near 160 mph and a minimum central pressure of 940 mb. As of 6:30 pm HST, Lane was located about 375 miles south-southeast of Kailua-Kona on the Big Island’s west coast, heading west-northwest at 9 mph.

Lane intensified steadily through the day Tuesday, with its central pressure dropping from 940 mb at 2 pm EDT to 929 mb by 11 pm EDT. Data from a reconnaissance flight on Tuesady night showed that Lane was strengthening even further, with an extrapolated central pressure of 922 mb and an SFMR surface wind estimate of 152 knots (175 mph) reported just before midnight EDT.

This remarkable bout of intensification won't go on forever, and fluctuations in Lane’s intensity can be expected on Wednesday, which could easily be enough to bring Lane back below the Category 5 threshold. Regardless, the key message is this: Lane is a formidable hurricane and should remain so through the day on Wednesday. The 0Z Wednesday run of the SHIPS model indicates that wind shear will not increase significantly over Lane until at least Thursday morning, and sea surface temperatures will remain in the 27-28°C range (81-82°F), so these should not induce any major weakening on Wednesday.

The timing of eyewall replacement cycles is difficult to predict, but if one happens to take place on Wednesday, which is quite possible, Lane’s strength could drop by roughly a Saffir-Simpson category for roughly a day. In this case, the hurricane might run out of time to return to its previous peak strength before drawing closer to the islands....MORE
Forecast track and “cone of uncertainty” for Lane as of 6 PM HST Tuesday, August 20, 2018
Figure 3. Forecast track and “cone of uncertainty” for Lane as of 6 PM HST Tuesday, August 20, 2018 (midnight Tuesday night EDT). The cones are constructed based on typical forecast errors over the past few years such that a hurricane can be expected to fall within the cone about two-thirds of the time. The cone suggests that Lane could remain well west of the Big Island—or could make landfall on the west coast. Image credit: NOAA/NWS/CPHC.