Winds will veer to the east-southeast and strengthen as Hurricane Lowell approaches. The center of Lowell is forecast to pass west of of Kauai tonight, but close enough that a Hurricane Warning is in effect for Kauai and Niihau and a Tropical Storm Warning is in now place for Oahu. High surf and heavy rain will impact all islands with strong winds mainly impacting the western end of the state.
Hurricane Lowell is about 325 statute miles southwest of Kauai this morning moving north northeastward. Lowell's track has shifted eastward closer to Kauai and Niihau with advisory updates this morning, and the core of Lowell is expected to pass west of the Kauai. This has again has raised the possibility of hurricane force winds reaching Kauai and Niihau and Tropical Storm force winds reaching Oahu, as a result a Hurricane Warning has been issued for Kauai and Niihau. A Tropical Storm warning is also in place for Oahu due to this eastward shift. On satellite imagery this morning, a band of heavy rain with some embedded thunder is approaching south of the Big Island's southeast slopes. We will be monitoring the progression of this rain band among many other things.
Additional impacts from Lowell are expected statewide, and a few headlines are in effect as a result. A High Surf Warning for south facing shores for the south swell generated by Lowell for all islands, along with the west facing shores of the Big Island. A High Surf Advisory remains in effect for the east swell generated by former Tropical Storm Karina, which has weakened to a post tropical low. For surf and other marine impacts, please see the marine section of the discussion below.
The Flood Watch for the state continues through Tuesday due to heavy rain brought in by Lowell and associated rain and thunderstorm bands. Terrain influence will play a big factor with isolated areas receiving significant amounts through the event. Stay alert for the issuance of any future flood advisories or warnings across the state. See hydrology section for additional information.
The threat of short-lived, fast-moving tornados/waterspouts will be present mainly near Kauai and Niihau as Lowell makes its closest approach to the islands. These would likely be embedded in rainbands. The threat for tornadoes is lower near the remaining islands, but not zero. The threat for tornadoes should decrease quickly early Tuesday morning.
Any deviation in track or intensity could also change how these hazards effect the islands.
High pressure is forecast to build back in Thursday through Saturday, bringing in a more typical trade wind pattern. Moisture may take a bit longer to exit the area as well, so conditions are expected to dry out more gradually into the weekend.
Hurricane Lowell continues its track northward, advecting unstable deep tropical moisture northward into the islands. Shower activity will continue to trend higher into Tuesday. MVFR conditions with low cloud ceilings and showers are expected statewide. Heavier showers will produce periods of IFR conditions. Surface winds will strengthen today over the western half of the state, as Hurricane Lowell continues on a northern track.
AIRMET Sierra for mountain obscuration continues for Kauai Oahu Molokai Maui and the Big Island. This AIRMET will likely continue into Tuesday.
AIRMET Tango was issued for moderate low level turbulence affecting the island of Kauai over and SW thru NW of island mountains. A strong surface wind AIRMET will likely be issued for Kauai and Niihau later today for wind speeds greater than 30 knots due to Hurricane Lowell approaching the islands.
Light icing continues in a layer between 160 and FL220 due to strengthening low level wind speeds as Lowell approaches the island.
Hurricane Lowell, located southwest of the islands, continues to move north-northeast this morning. As it approaches the island chain wind speeds will increase. A Hurricane Warning remains in effect for waters west of Kauai County, while a Tropical Storm Warning remains in effect for Kauai Channel and Kauai Windward Waters through Tuesday afternoon. A slight eastward shift in the track has also prompted the issuance of Tropical Storm Warnings for Oahu Leeward and Windward Waters. The Small Craft Advisory remains in effect for all remaining coastal waters for a combination of winds and seas through Tuesday. Winds are expected to increasingly veer to the southeast to south as Lowell approaches and the strongest winds and highest seas are expected for the western end of the state.
Hurricane conditions are expected in the western offshore waters as Lowell through Tuesday as the center of the storm tracks just west of Niihau. Any slight deviation in the track to the west or east in the next 24 hours will have significant differences in impact for the coastal waters around Kauai County. Post-Tropical Cyclone Karina to the northeast of the islands will continue to weaken and dissipate later today.
South-southwest swell from Hurricane Lowell will rapidly build today. As a result, surf along south facing shores will begin to rise from advisory levels this morning to warning levels by this afternoon and peak overnight. The swell will increasingly shift out of the southwest tonight. Due to the track of Lowell west of the main islands, a sharp gradient in swell is expected from west to east. This will bring damaging surf to portions of Kauai County and possibly Oahu. Coinciding also with the peak monthly afternoon high tides, this could bring the potential for significant damage to coastal properties and infrastructure, including roadways to portions of Kauai and possibly Oahu. Swell energy is expected to rapidly decline on Tuesday.
A moderate, long-period south swell also arrives today and peaks overnight into Tuesday, but will be overwhelmed by the larger swell from Hurricane Lowell. Although it begins to fade on Tuesday, it will keep south shore surf somewhat elevated through Thursday. A large, medium-period east swell from former Tropical Storm Karina will combine with increasing east to southeast wind wave generated by Hurricane Lowell to keep advisory level surf along east facing shores through Tuesday. Surf along north facing shores will also experience a small increase on Tuesday as Lowell lifts north of the island chain and then fade through the week.
Flood Watch through Tuesday afternoon for all Hawaii islands-
High Surf Warning until 6 PM HST Tuesday for Niihau-Kauai Leeward-Waianae Coast-Kahoolawe-Maui Leeward West-Kona-Kohala- Kauai South-East Honolulu-Honolulu Metro-Ewa Plain-Molokai Southeast-Molokai West-Molokai Leeward South-Lanai Leeward-Lanai South-Maui Central Valley South-Kipahulu-South Maui/Upcountry- South Haleakala-Big Island South-Big Island Southeast.
Hurricane Warning for Niihau-Kauai-
Tropical Storm Warning for Oahu-
High Surf Advisory until 6 PM HST Tuesday for Olomana-Kauai East- Koolau Windward-Molokai Windward-Windward Haleakala-Big Island East-Big Island North.
Hurricane Warning for Kauai Northwest Waters-Kauai Leeward Waters.
Tropical Storm Warning for Kauai Windward Waters-Kauai Channel- Oahu Windward Waters-Oahu Leeward Waters.
Small Craft Advisory until 6 PM HST Tuesday for Kaiwi Channel- Maui County Windward Waters-Maui County Leeward Waters-Maalaea Bay-Pailolo Channel-Alenuihaha Channel-Big Island Windward Waters-Big Island Leeward Waters-Big Island Southeast Waters.
