Tropical Storm Nolo will intensity to a hurricane as it drifts northward toward Big Island through Friday night. Deepening moisture along the northern edge of the system will gradually increase rainfall across the Big Island and Maui, leading to the potential for significant flash flooding on windward and southeast Big Island. Big Island remains under a Hurricane Watch with the potential for damaging winds Friday and Saturday, and locally windy trade winds will develop across the rest of the island chain Friday. Nolo is expected to move westward on Sunday, but all interests in Hawaii should monitor the progress of the system as impacts could persist through the weekend.
Breezy and gusty trades through the next 24 hours. Tropical Storm Nolo is quasi-stationary about 290 miles south of the Big Island. As Nolo approaches, expect winds to increase especially across the eastern end of the state. Showers will increase and be heavy at times, particularly over windward Big Island. TSTMs are possible but confidence is low on exactly where as such elected not to include those in the TAFs at this time. Conditions will deteriorate as Nolo nears, potentially bringing LIFR to MVFR across the Big Island. MVFR/VFR is expected for the rest of the state. Maui could also see deteriorating conditions later this week.
AIRMET Sierra is in effect for mountain obscurations for Oahu, Maui, and the Big Island. Expect this to expand as Tropical Storm Nolo gets closer.
AIRMET Tango is in effect for low level turbulence downwind of terrain.
TC SIGMET Series Oscar covers Tropical Storm Nolo.
Tropical Storm Nolo continues to strengthen this morning as the storm system is forecast to slowly drift northward towards the Big Island. Impacts with Nolo include increasing south and east swell, winds, and rainfall lasting through the weekend. Marine impacts will highly depend upon the final track and intensity as Nolo continues to approach the Big Island from the south. Nolo is currently expected to continue on a slow northward trend through Friday with increasing waves along exposed south facing shores of the Big Island, before a forecast turn to the west this weekend with potential wind, weather and wave impacts to all coastal waters through the weekend.
The Hurricane Watch continues for waters surrounding the Big Island this morning, including the Alenuihaha Channel. A Small Craft Advisory remains in effect for the rest of the coastal waters and channels. A Gale Watch continues for Friday for the Pailolo Channel and Maalaea Bay due to strengthening trade winds.
The current small south swell continue to fade, as another small overlapping southwest swell builds in from Friday into the weekend. Tropical Storm Nolo is expected to strengthen into a hurricane later today, and will likely produce a southerly swell into at least High Surf Advisory thresholds for exposed south facing shorelines, initially for the Big Island and then a brief period of higher surf expanding westward across the state later this weekend as the center of Nolo drifts westward and passes just south of the Hawaiian Islands.
A new small, long period, northwest swell will fill in this weekend keeping surf slightly elevated along north and west facing shores into early next week. East facing shores will maintain rough, short period wind waves generated from the strengthening trade winds. Surf along east facing shores could reach advisory levels as the trades strengthen on Friday.
Flood Watch through Saturday afternoon for Big Island East-Big Island Interior-Big Island North-Big Island South-Big Island Southeast-Big Island Summits-Haleakala Summit-Kahoolawe-Kipahulu- Kohala-Kona-Lanai Leeward-Lanai Mauka-Lanai South-Lanai Windward- Maui Central Valley North-Maui Central Valley South-Maui Leeward West-Maui Windward West-Molokai Leeward South-Molokai North- Molokai Southeast-Molokai West-Molokai Windward-South Haleakala- South Maui/Upcountry-Windward Haleakala.
Hurricane Watch for Big Island East-Big Island Interior-Big Island North-Big Island South-Big Island Southeast-Big Island Summits-Kohala-Kona.
Hurricane Watch for Alenuihaha Channel-Big Island Leeward Waters- Big Island Southeast Waters-Big Island Windward Waters.
Small Craft Advisory from 6 AM Friday to 6 PM HST Saturday for Kauai Leeward Waters-Kauai Northwest Waters-Kauai Windward Waters.
Small Craft Advisory until 6 PM HST Saturday for Kaiwi Channel- Kauai Channel-Maui County Leeward Waters-Maui County Windward Waters-Oahu Leeward Waters-Oahu Windward Waters.
Small Craft Advisory until 6 AM HST Friday for Alenuihaha Channel-Big Island Leeward Waters-Big Island Southeast Waters- Big Island Windward Waters-Maalaea Bay-Pailolo Channel.
Gale Watch from Friday morning through Saturday afternoon for Maalaea Bay-Pailolo Channel.
