High Surf Advisory 6, NWS Honolulu, HI

543 
WHHW40 PHFO 170148
CFWHFO

Coastal Hazard Message
National Weather Service Honolulu HI
348 PM HST Sat Jan 16 2021

...HIGH SURF WARNING FOR NORTH AND WEST FACING SHORES OF NIIHAU
KAUAI OAHU MOLOKAI AND NORTH FACING SHORES OF MAUI... 

...HIGH SURF ADVISORY FOR NORTH AND WEST FACING SHORES OF THE BIG
ISLAND...

.A giant northwest will continue to move down the island chain 
peaking on Oahu late this afternoon to early this evening, and 
this evening on Maui. Some of the swell's energy is expected to 
reach portions of the Big Island later in the day, peaking 
overnight. A gradual decrease in wave heights is expected on 
Sunday, but another large swell is expected to arrive by Monday.

HIZ001>003-006>009-012-013-017-019-020-171500-
/O.EXT.PHFO.SU.W.0003.000000T0000Z-210118T0400Z/
Niihau-Kauai Windward-Kauai Leeward-Waianae Coast-
Oahu North Shore-Oahu Koolau-Olomana-Molokai Windward-
Molokai Leeward-Maui Windward West-Maui Central Valley-
Windward Haleakala-
348 PM HST Sat Jan 16 2021

...HIGH SURF WARNING NOW IN EFFECT UNTIL 6 PM HST SUNDAY...

* WHAT...Surf 40 to 50 feet along north facing shores, and 25 to 
  35 feet along west facing shores.

* WHERE...North and west facing shores of Niihau, Kauai, Oahu 
  and Molokai, and north facing shores of Maui.

* WHEN...Until 6 PM HST Sunday.

* IMPACTS...Very High...Expect ocean water surging and sweeping 
  across beaches, coastal benches, and lava flows creating the 
  potential for impacts to coastal properties and 
  infrastructure, including roadways. Powerful longshore and rip 
  currents will be present at most beaches. Large breaking waves 
  and strong currents may impact harbor entrances and channels 
  causing challenging boat handling.


PRECAUTIONARY/PREPAREDNESS ACTIONS...

Large, breaking surf, significant shorebreak, and dangerous
currents make entering the water very hazardous.

Anyone entering the water could face significant injury or death.


&&

$$

HIZ023-025-026-171500-
/O.CON.PHFO.SU.Y.0006.000000T0000Z-210118T0400Z/
Kona-Big Island North and East-Kohala-
348 PM HST Sat Jan 16 2021

...HIGH SURF ADVISORY REMAINS IN EFFECT UNTIL 6 PM HST SUNDAY...

* WHAT...Surf of 12 to 16 feet.

* WHERE...North facing shores of the Big Island.

* WHEN...From noon today to 6 PM HST Sunday.

* IMPACTS...Moderate. Expect strong breaking waves, shore break, 
  and strong longshore and rip currents making swimming 
  difficult and dangerous.


PRECAUTIONARY/PREPAREDNESS ACTIONS...

Beachgoers, swimmers, and surfers should heed all advice given by
ocean safety officials and exercise caution.

Boaters should expect recreational surfers and body boarders
utilizing harbor channels to access surfing areas.

&&

$$

671 
WHHW40 PHFO 170528
CFWHFO

Coastal Hazard Message
National Weather Service Honolulu HI
728 PM HST Sat Jan 16 2021

...HIGH SURF WARNING FOR NORTH AND WEST FACING SHORES OF NIIHAU
KAUAI OAHU MOLOKAI AND NORTH FACING SHORES OF MAUI...
...HIGH SURF ADVISORY FOR NORTH AND WEST FACING SHORES OF THE BIG
ISLAND...

.A giant northwest swell will gradually diminish in Kauai and 
Oahu waters overnight, while peaking in Maui County and Big Island
waters. Surf will drop on Sunday, and will briefly diminish below
warning levels statewide by Sunday evening. However, another 
giant swell will follow Sunday night and Monday, once again 
producing warning-level surf along most north and west facing 
shores. 

HIZ001>003-006>009-012-013-017-019-020-171830-
/O.CON.PHFO.SU.W.0003.000000T0000Z-210118T0400Z/
Niihau-Kauai Windward-Kauai Leeward-Waianae Coast-
Oahu North Shore-Oahu Koolau-Olomana-Molokai Windward-
Molokai Leeward-Maui Windward West-Maui Central Valley-
Windward Haleakala-
728 PM HST Sat Jan 16 2021

...HIGH SURF WARNING REMAINS IN EFFECT UNTIL 6 PM HST SUNDAY...

* WHAT...Peak surf heights of 40 to 50 feet along north facing
  shores of Maui County through early Sunday, then diminishing.
  Surf 30 to 45 feet along north facing shores of Kauai County and
  Oahu overnight. Surf 20 to 30 feet along west facing shores of
  Kauai County, Oahu and Molokai overnight. Surf will gradually
  diminish on Sunday, but still remain dangerously large. 

* WHERE...North and west facing shores of Niihau, Kauai, Oahu 
  and Molokai, and north facing shores of Maui.

* WHEN...Until 6 PM HST Sunday.

* IMPACTS...Very High...Expect ocean water surging and sweeping 
  across beaches, coastal benches, and lava flows creating the 
  potential for impacts to coastal properties and 
  infrastructure, including roadways. Powerful longshore and rip 
  currents will be present at most beaches. Large breaking waves 
  and strong currents may impact harbor entrances and channels 
  causing challenging boat handling.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

Large, breaking surf, significant shorebreak, and dangerous
currents make entering the water very hazardous.

Anyone entering the water could face significant injury or death.

&&

$$

HIZ023-025-026-171830-
/O.CON.PHFO.SU.Y.0006.000000T0000Z-210118T0400Z/
Kona-Big Island North and East-Kohala-
728 PM HST Sat Jan 16 2021

...HIGH SURF ADVISORY REMAINS IN EFFECT UNTIL 6 PM HST SUNDAY...

* WHAT...Along north facing shores of the Big Island, surf 12 to
  16 feet. Along west facing shores of the Big Island, surf 7 to 
  10 feet. 

* WHERE...North and west facing shores of the Big Island.

* WHEN...Until 6 PM HST Sunday.

* IMPACTS...Moderate. Expect strong breaking waves, shore break,
  and strong longshore and rip currents making swimming difficult
  and dangerous.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

Beachgoers, swimmers, and surfers should heed all advice given by
ocean safety officials and exercise caution. Know your limits and
seek ocean recreation areas best suited for your abilities. 

&&

$$

Birchard

961 
WHHW40 PHFO 171324
CFWHFO

Coastal Hazard Message
National Weather Service Honolulu HI
324 AM HST Sun Jan 17 2021

...HIGH SURF WARNING FOR NORTH AND WEST FACING SHORES OF NIIHAU
KAUAI OAHU MOLOKAI AND NORTH FACING SHORES OF MAUI... 
...HIGH SURF ADVISORY FOR NORTH AND WEST FACING SHORES OF THE BIG
ISLAND...

.Northwest swell will gradually diminish statewide through the day
today, with surf likely falling below warning levels by this
afternoon. However, another powerful northwest swell will arrive 
tonight and Monday, once again producing warning-level surf along 
exposed north and west facing shores.

HIZ001>003-006>009-012-013-017-019-020-180230-
/O.EXT.PHFO.SU.W.0003.000000T0000Z-210119T1600Z/
Niihau-Kauai Windward-Kauai Leeward-Waianae Coast-
Oahu North Shore-Oahu Koolau-Olomana-Molokai Windward-
Molokai Leeward-Maui Windward West-Maui Central Valley-
Windward Haleakala-
324 AM HST Sun Jan 17 2021

...HIGH SURF WARNING NOW IN EFFECT UNTIL 6 AM HST TUESDAY...

* WHAT...Surf 20 to 30 feet along north facing shores of Oahu,
  Molokai and Maui, and surf 15 to 20 feet along west facing
  shores of Oahu and Molokai through this morning. Surf will
  likely diminish below warning levels statewide by this
  afternoon, but surf will build to 30 to 45 feet along north 
  facing shores of Kauai tonight and early Monday as a new swell 
  arrives. This large swell will spread to Oahu and Maui through 
  the day Monday, producing warning-level surf heights. 

* WHERE...North and west facing shores of Niihau, Kauai, Oahu 
  and Molokai, and north facing shores of Maui.

* WHEN...Until 6 AM HST Tuesday.

* IMPACTS...High to Very high. Expect ocean water occasionally
  sweeping across portions of beaches, very strong breaking waves,
  and strong longshore and rip currents. 

PRECAUTIONARY/PREPAREDNESS ACTIONS...

Large, breaking surf, significant shorebreak, and dangerous
currents make entering the water very hazardous. Anyone entering 
the water could face significant injury or death.

&&

$$

HIZ023-025-026-180230-
/O.EXT.PHFO.SU.Y.0006.000000T0000Z-210119T1600Z/
Kona-Big Island North and East-Kohala-
324 AM HST Sun Jan 17 2021

...HIGH SURF ADVISORY NOW IN EFFECT UNTIL 6 AM HST TUESDAY...

* WHAT...Along north facing shores of the Big Island, surf 12 to
  16 feet. Along west facing shores of the Big Island, surf 7 to
  10 feet. Surf will gradually diminish later today and tonight,
  but another swell arriving on Monday will bring advisory-level
  surf again.

* WHERE...North and west facing shores of the Big Island.

* WHEN...Until 6 AM HST Tuesday.

* IMPACTS...Moderate. Expect strong breaking waves, shore break, 
  and strong longshore and rip currents making swimming 
  difficult and dangerous.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

Beachgoers, swimmers, and surfers should heed all advice given by
ocean safety officials and exercise caution. Know your limits; 
when in doubt, don't go out.

&&

$$

Birchard

504 
WHHW40 PHFO 180153
CFWHFO

Coastal Hazard Message
National Weather Service Honolulu HI
353 PM HST Sun Jan 17 2021

...HIGH SURF WARNING FOR NORTH AND WEST FACING SHORES OF NIIHAU
KAUAI OAHU MOLOKAI AND NORTH FACING SHORES OF MAUI... 

...HIGH SURF ADVISORY FOR NORTH AND WEST FACING SHORES OF THE BIG
ISLAND...

.A large northwest swell will arrive overnight Monday morning that
will once again produce warning level surf along exposed the
northern and western exposed shorelines of the smaller islands.
Surf will peak at advisory levels along the Big Island's north and
west facing shorelines Monday.

HIZ001>003-006>009-012-013-017-019-020-181500-
/O.CON.PHFO.SU.W.0003.000000T0000Z-210119T1600Z/
Niihau-Kauai Windward-Kauai Leeward-Waianae Coast-
Oahu North Shore-Oahu Koolau-Olomana-Molokai Windward-
Molokai Leeward-Maui Windward West-Maui Central Valley-
Windward Haleakala-
353 PM HST Sun Jan 17 2021

...HIGH SURF WARNING REMAINS IN EFFECT UNTIL 6 AM HST TUESDAY...

* WHAT...Surf 30 to 40 feet along the north-facing shores of
  Niihau, Kauai, Oahu, Molokai and Maui, with 15 to 20 foot surf
  along the west-facing shores of Niihau, Kauai, Oahu and 
  Molokai. Large northwest swells will spread across Oahu and Maui
  through the day Monday, producing warning level surf heights.

* WHERE...North and west-facing shores of Niihau, Kauai, Oahu and
  Molokai, and north-facing shores of Maui.

* WHEN...Until 6 AM HST Tuesday.

* IMPACTS...High to Very high. Expect ocean water occasionally 
  sweeping across portions of beaches, very strong breaking 
  waves, and strong longshore and rip currents.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

Large, breaking surf, significant shorebreak, and dangerous
currents make entering the water very hazardous.

Anyone entering the water could face significant injury or death.

Boaters should be aware of an increased number of surfers and
body boarders utilizing the harbor channel to access surfing
areas.

&&

$$

HIZ023-025-026-181500-
/O.CON.PHFO.SU.Y.0006.000000T0000Z-210119T1600Z/
Kona-Big Island North and East-Kohala-
353 PM HST Sun Jan 17 2021

...HIGH SURF ADVISORY REMAINS IN EFFECT UNTIL 6 AM HST TUESDAY...

* WHAT...Along north-facing shores of the Big Island, surf 12 to
  16 feet. Along west-facing shores of the Big Island, surf 8 to 
  12 feet. Surf will gradually diminish through tonight, but large
  northwest swells will arrive Monday will and introduce advisory
  level surf.

* WHERE...North and west-facing shores of the Big Island.

* WHEN...Until 6 AM HST Tuesday.

* IMPACTS...Moderate. Expect strong breaking waves, shore break, 
  and strong longshore and rip currents making swimming 
  difficult and dangerous.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

Beachgoers, swimmers, and surfers should heed all advice given by
ocean safety officials and exercise caution.

Boaters should expect recreational surfers and body boarders
utilizing harbor channels to access surfing areas.

&&

$$

599 
WHHW40 PHFO 181313
CFWHFO

Coastal Hazard Message
National Weather Service Honolulu HI
313 AM HST Mon Jan 18 2021

...HIGH SURF WARNING FOR NORTH AND WEST FACING SHORES OF NIIHAU
KAUAI OAHU MOLOKAI AND NORTH FACING SHORES OF MAUI...

...HIGH SURF ADVISORY FOR NORTH AND WEST FACING SHORES OF THE BIG
ISLAND...

.A large northwest swell will be spreading down the island chain
today and tonight, producing another round of warning level surf 
for the exposed north and west shorelines of most of the smaller 
islands. Advisory level surf will reach the Big Island's north and
west facing shores this afternoon.


HIZ001>003-006>009-012-013-017-019-020-190215-
/O.CON.PHFO.SU.W.0003.000000T0000Z-210119T1600Z/
Niihau-Kauai Windward-Kauai Leeward-Waianae Coast-
Oahu North Shore-Oahu Koolau-Olomana-Molokai Windward-
Molokai Leeward-Maui Windward West-Maui Central Valley-
Windward Haleakala-
313 AM HST Mon Jan 18 2021

...HIGH SURF WARNING REMAINS IN EFFECT UNTIL 6 AM HST TUESDAY...

* WHAT...At its peak, surf will be 35 to 45 feet along the north-
  facing shores of Niihau, Kauai, and 30 to 40 feet along the
  north facing shores of Oahu, Molokai and Maui. Expect surf along
  the west facing shores of Niihau and Kauai of 28 to 36 feet, and
  20 to 30 feet along the west facing shores of Oahu and Molokai.
 
* WHERE...North and west-facing shores of Niihau, Kauai, Oahu 
  and Molokai, and north-facing shores of Maui.

* WHEN...Until 6 AM HST Tuesday.

* IMPACTS...High to Very high. Expect ocean water occasionally 
  sweeping across portions of beaches, very strong breaking 
  waves, and strong longshore and rip currents.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

Large, breaking surf, significant shorebreak, and dangerous
currents make entering the water very hazardous.

Anyone entering the water could face significant injury or death.

Boaters should be aware of an increased number of surfers and
body boarders utilizing the harbor channel to access surfing
areas.

&&

$$

HIZ023-025-026-190215-
/O.CON.PHFO.SU.Y.0006.000000T0000Z-210119T1600Z/
Kona-Big Island North and East-Kohala-
313 AM HST Mon Jan 18 2021

...HIGH SURF ADVISORY REMAINS IN EFFECT UNTIL 6 AM HST TUESDAY...

* WHAT...Along north-facing shores of the Big Island, surf 12 to 
  16 feet. Along west-facing shores of the Big Island, surf 8 to 
  12 feet. Surf will gradually diminish through tonight, but 
  large northwest swells will arrive Monday will and introduce 
  advisory level surf.

* WHERE...North and west-facing shores of the Big Island.

* WHEN...Until 6 AM HST Tuesday.

* IMPACTS...Moderate. Expect strong breaking waves, shore break, 
  and strong longshore and rip currents making swimming 
  difficult and dangerous.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

Beachgoers, swimmers, and surfers should heed all advice given by
ocean safety officials and exercise caution.

Boaters should expect recreational surfers and body boarders
utilizing harbor channels to access surfing areas.

&&

$$

180 
WHHW40 PHFO 190219
CFWHFO

Coastal Hazard Message
National Weather Service Honolulu HI
419 PM HST Mon Jan 18 2021

...HIGH SURF WARNING FOR NORTH AND WEST FACING SHORES OF NIIHAU
KAUAI OAHU MOLOKAI AND NORTH FACING SHORES OF MAUI...

...HIGH SURF ADVISORY FOR NORTH AND WEST FACING SHORES OF THE BIG
ISLAND...

.An extra large northwest swell is spreading down the island 
chain and will produce another round of warning level surf for 
the majority of the smaller island exposed northern and western 
shorelines. Surf will achieve advisory levels along the Big 
Island's north and west facing shores.

HIZ001>003-006>009-012-013-017-019-020-191530-
/O.CON.PHFO.SU.W.0003.000000T0000Z-210119T1600Z/
Niihau-Kauai Windward-Kauai Leeward-Waianae Coast-
Oahu North Shore-Oahu Koolau-Olomana-Molokai Windward-
Molokai Leeward-Maui Windward West-Maui Central Valley-
Windward Haleakala-
419 PM HST Mon Jan 18 2021

...HIGH SURF WARNING REMAINS IN EFFECT UNTIL 6 AM HST TUESDAY...

* WHAT...25 to near 40 foot surf along the north facing shores of
  Niihau, Kauai, Oahu, Molokai and Maui through early Tuesday
  morning. Surf along the west facing shores of Niihau and Kauai
  will peak in the 17 to 28 foot range, 17 to 25 feet along the
  west facing shores of Oahu and Molokai. Surf will gradually 
  diminish through Tuesday.

* WHERE...North and west facing shores of Niihau, Kauai, Oahu and
  Molokai, and north facing shores of Maui.

* WHEN...Until 6 AM HST Tuesday.

* IMPACTS...Very high. Expect ocean water occasionally sweeping 
  across portions of beaches, very strong breaking waves, and 
  strong longshore and rip currents.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

Large, breaking surf, significant shorebreak, and dangerous
currents make entering the water very hazardous.

Anyone entering the water could face significant injury or death.

Boaters should be aware of an increased number of surfers and
body boarders utilizing the harbor channel to access surfing
areas.

&&

$$

HIZ023-025-026-191530-
/O.CON.PHFO.SU.Y.0006.000000T0000Z-210119T1600Z/
Kona-Big Island North and East-Kohala-
419 PM HST Mon Jan 18 2021

...HIGH SURF ADVISORY REMAINS IN EFFECT UNTIL 6 AM HST TUESDAY...

* WHAT...Surf 12 to 18 feet along the north facing shores of the
  Big Island. Surf 6 to 10 feet along the west facing shores of
  the Big Island. Surf will gradually diminish through Tuesday 
  morning.

* WHERE...North and west facing shores of the Big Island.

* WHEN...Until 6 AM HST Tuesday.

* IMPACTS...Moderate. Expect strong breaking waves, shore break, 
  and strong longshore and rip currents making swimming 
  difficult and dangerous.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

Beachgoers, swimmers, and surfers should heed all advice given by
ocean safety officials and exercise caution.

Boaters should expect recreational surfers and body boarders
utilizing harbor channels to access surfing areas.

&&

$$

960 
WHHW40 PHFO 191332
CFWHFO

Coastal Hazard Message
National Weather Service Honolulu HI
332 AM HST Tue Jan 19 2021

...HIGH SURF WARNING FOR NORTH AND WEST FACING SHORES OF KAUAI
NIIHAU OAHU AND MOLOKAI AND FOR NORTH FACING SHORES OF MAUI...
...HIGH SURF ADVISORY FOR NORTH AND WEST FACING SHORES OF THE BIG
ISLAND...

.Very large and rough surf will continue this morning along most 
north and west facing shores of the smaller islands due to a 
large northwest swell and strong northeast winds. Therefore, the 
High Surf Warning has been extended through noon HST today. 
Elsewhere, surf is expected to remain near the High Surf Advisory
threshold along north and west facing shores of the Big Island. 
By this afternoon, expect most of the shorelines in the High Surf
Warning to require a High Surf Advisory due to continued 
elevated, rough surf conditions. 

HIZ001>003-006>009-012-013-017-019-020-192200-
/O.EXT.PHFO.SU.W.0003.000000T0000Z-210119T2200Z/
Niihau-Kauai Windward-Kauai Leeward-Waianae Coast-
Oahu North Shore-Oahu Koolau-Olomana-Molokai Windward-
Molokai Leeward-Maui Windward West-Maui Central Valley-
Windward Haleakala-
332 AM HST Tue Jan 19 2021

...HIGH SURF WARNING NOW IN EFFECT UNTIL NOON HST TODAY...

* WHAT...Large breaking waves of 20 to 25 feet along north facing
  shores of Kauai, Niihau, Oahu, Molokai and Maui. Surf will be 15
  to 20 feet along west facing shores of Kauai, Niihau, Oahu, and
  Molokai.

* WHERE...North and west facing shores of Kauai, Niihau, Oahu, 
  and Molokai, and for north facing shores of Maui.

* WHEN...Through this morning.

* IMPACTS...High. Expect ocean water occasionally sweeping across
  portions of beaches, very strong breaking waves, and strong 
  longshore and rip currents. 

PRECAUTIONARY/PREPAREDNESS ACTIONS...

Large, breaking surf, significant shorebreak, and dangerous
currents make entering the water very hazardous.

&&

$$

HIZ023-025-026-192200-
/O.EXT.PHFO.SU.Y.0006.000000T0000Z-210119T2200Z/
Kona-Big Island North and East-Kohala-
332 AM HST Tue Jan 19 2021

...HIGH SURF ADVISORY NOW IN EFFECT UNTIL NOON HST TODAY...

* WHAT...Surf heights of 10 to 15 feet along north facing shores
  of the Big Island, and 5 to 8 feet along west facing shores of 
  the Big island.

* WHERE...North and west facing shores of the Big Island.

* WHEN...Through this morning.

* IMPACTS...Moderate. Expect strong breaking waves, shore break, 
  and strong longshore and rip currents making swimming 
  difficult and dangerous.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

Beachgoers, swimmers, and surfers should heed all advice given by
ocean safety officials and exercise caution.

&&

$$

Houston

360 
WHHW40 PHFO 191929
CFWHFO

Coastal Hazard Message
National Weather Service Honolulu HI
929 AM HST Tue Jan 19 2021

...HIGH SURF ADVISORY FOR NORTH AND WEST FACING SHORES OF KAUAI 
NIIHAU OAHU MOLOKAI BIG ISLAND AND FOR NORTH FACING SHORES OF 
MAUI... 

.Rough surf along exposed north and west facing shores will 
slowly diminish through tonight. 

HIZ001>003-006>009-012-013-017-019-020-200830-
/O.CAN.PHFO.SU.W.0003.000000T0000Z-210119T2200Z/
/O.EXB.PHFO.SU.Y.0006.000000T0000Z-210120T1600Z/
Niihau-Kauai Windward-Kauai Leeward-Waianae Coast-
Oahu North Shore-Oahu Koolau-Olomana-Molokai Windward-
Molokai Leeward-Maui Windward West-Maui Central Valley-
Windward Haleakala-
929 AM HST Tue Jan 19 2021

...HIGH SURF ADVISORY IN EFFECT UNTIL 6 AM HST WEDNESDAY...
...HIGH SURF WARNING IS CANCELLED...

* WHAT...Surf 18 to 24 feet along north facing shores, lowering to
  15 to 20 feet tonight. Surf 12 to 18 feet along west facing 
  shores, lowering to 8 to 12 feet tonight.

* WHERE...North and west facing shores of Kauai, Niihau, Oahu, and
  Molokai, and for north facing shores of Maui. 

* WHEN...Until 6 AM HST Wednesday.

* IMPACTS...Moderate. Expect strong breaking waves, shore break,
  and strong longshore and rip currents making swimming difficult
  and dangerous.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

Beachgoers, swimmers, and surfers should heed all advice given by
ocean safety officials and exercise caution. Know your limits; 
when in doubt, do not go out.

&&

$$

HIZ023-025-026-200830-
/O.EXT.PHFO.SU.Y.0006.000000T0000Z-210120T1600Z/
Kona-Big Island North and East-Kohala-
929 AM HST Tue Jan 19 2021

...HIGH SURF ADVISORY NOW IN EFFECT UNTIL 6 AM HST WEDNESDAY...

* WHAT...Surf 10 to 15 feet along north facing shores, and 5 to 8
  feet along west facing shores. Surf will gradually diminish
  through tonight.

* WHERE...North and west facing shores of the Big Island.

* WHEN...Until 6 AM HST Wednesday.

* IMPACTS...Moderate. Expect strong breaking waves, shore break,
  and strong longshore and rip currents making swimming  
  difficult and dangerous.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

Beachgoers, swimmers, and surfers should heed all advice given by
ocean safety officials and exercise caution. Know your limits; 
when in doubt, do not go out.

&&

$$

Birchard

047 
WHHW40 PHFO 200116
CFWHFO

Coastal Hazard Message
National Weather Service Honolulu HI
316 PM HST Tue Jan 19 2021

...HIGH SURF ADVISORY THROUGH 6 AM HST WEDNESDAY FOR NORTH AND 
WEST FACING SHORES OF KAUAI NIIHAU OAHU MOLOKAI BIG ISLAND AND 
FOR NORTH FACING SHORES OF MAUI...

.Rough surf along exposed north and west facing shores will
slowly diminish through Wednesday.

HIZ001>003-006>009-012-013-017-019-020-023-025-026-201430-
/O.CON.PHFO.SU.Y.0006.000000T0000Z-210120T1600Z/
Niihau-Kauai Windward-Kauai Leeward-Waianae Coast-
Oahu North Shore-Oahu Koolau-Olomana-Molokai Windward-
Molokai Leeward-Maui Windward West-Maui Central Valley-
Windward Haleakala-Kona-Big Island North and East-Kohala-
316 PM HST Tue Jan 19 2021

...HIGH SURF ADVISORY REMAINS IN EFFECT UNTIL 6 AM HST
WEDNESDAY...

* WHAT...On the smaller islands, surf 16 to 20 feet along north
  facing shores, and 12 to 16 feet along west facing shores. On
  the Big Island, surf 10 to 15 feet along north facing shores,
  and 5 to 8 feet along west facing shores.

* WHERE...North and west facing shores of Kauai, Niihau, Oahu,
  Molokai and the Big Island, and north facing shores of Maui.

* WHEN...Until 6 AM HST Wednesday.

* IMPACTS...Moderate. Expect strong breaking waves, shore break, 
  and strong longshore and rip currents making swimming 
  difficult and dangerous.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

Beachgoers, swimmers, and surfers should heed all advice given by
ocean safety officials and exercise caution. Know your limits;
when in doubt, do not go out.

&&

$$

Birchard

093 
WHHW40 PHFO 201354
CFWHFO

Coastal Hazard Message
National Weather Service Honolulu HI
354 AM HST Wed Jan 20 2021

...HIGH SURF ADVISORY IS CANCELLED...

.Subsiding north swells have lowering surf to below high surf 
advisory levels.

HIZ001>003-006>009-012-013-017-019-020-023-025-026-201500-
/O.CAN.PHFO.SU.Y.0006.000000T0000Z-210120T1600Z/
Niihau-Kauai Windward-Kauai Leeward-Waianae Coast-
Oahu North Shore-Oahu Koolau-Olomana-Molokai Windward-
Molokai Leeward-Maui Windward West-Maui Central Valley-
Windward Haleakala-Kona-Big Island North and East-Kohala-
354 AM HST Wed Jan 20 2021

...HIGH SURF ADVISORY IS CANCELLED...

Subsiding north swells have lowering surf to below high surf 
advisory levels.

$$

Area Forecast Discussion
National Weather Service Honolulu HI
328 AM HST Sat Jan 16 2021

.SYNOPSIS...
Light to moderate trade winds will continue today with clouds and
showers favoring windward and mountain areas. Rainfall chances
will quickly rise through the day Sunday as the winds shift out of
the south to southwest ahead of a strong cold front approaching.
This front will quickly advance down the island chain Sunday
night, then stall around the Big Island Monday through Tuesday.
Heavy showers and a few thunderstorms will be possible along ahead
of this front. Cool and gusty northerly winds are expected
following the frontal passage over the western end of the state
early next week. Trade winds may return late next week.

&&

.DISCUSSION...
Short-term guidance has initialized well with the current pattern
and depicts mostly dry conditions with light to moderate trade
winds continuing across much of the area today. The exception
will be over and around Kauai where showery conditions will remain
possible due to a trough nearby.

A transition period is expected tonight through Sunday as a cold
front associated with a gale currently north of Midway approaches.
Low-level winds will quickly shift out of the south and southwest
ahead of this approaching boundary - potentially increasing to
moderate levels over and around Kauai/Oahu later Sunday.
Increasing instability and lift out ahead of this front and its
attendant shortwave trough aloft will be enough to trigger spotty
pre-frontal showers Sunday afternoon over Kauai and Oahu.

The cold front is forecast to reach Kauai late Sunday, then move
down the island chain Sunday night through Monday. Model
reflectivities are in decent agreement and depict the leading edge
of the main line of showers along the front reaching Kauai late
Sunday afternoon, then to Oahu and Maui County Sunday night.
Lowering upper heights combined with 40-50 kt 0-6 km shear ahead
of this upper trough will support a few thunderstorms Sunday night
into Monday. The one limiting factor with regard to the strength
of these storms could be the phasing between the upper trough and
deep moisture axis along the front (appears to be a lag in the
latest model cycle). If these were to align, a few strong storms
can't be ruled out - especially over the coastal waters Sunday
night.

Gusty northerly winds (potentially reaching advisory levels
beginning Sunday night) and cool conditions will follow the
frontal passage across the western end of the state early next
week. Guidance reflects this and depicts dewpoints dipping into
the 50s for Kauai and Oahu.

There remains subtle differences in the global models on how far
east the front will progress before stalling. The GFS moves the
front to just east of the Big Island on Tuesday while the ECMWF
has the front stalling over the Big Island. Either way, the Big
Island and possibly east Maui will remain rather wet on into
Wednesday, which could result in localized flooding concerns.

Winter weather conditions can't be ruled out over the Big Island
summits Monday night into midweek due to a combination of the deep
moisture axis associated with the front hanging up or stalling and
cold temperatures aloft arriving with the shortwave trough.

As we head on into Thursday, high pressure will build in northeast
of the area resulting in strengthening trade winds. Moisture
associated with the frontal boundary is then forecast to move back
westward likely providing for a wet trade wind pattern to set up
across the state. With the differences in the long range models
continuing, changes to the forecast our possible next week.

&&

.AVIATION...
A weak surface trough has stalled northwest of Kauai, and its
influence on the weather over Hawaii is diminishing early this
morning. Light to moderate low-level trade winds appear to be
filling in across most of the state, including Kauai. The trade
winds will deliver low clouds and isolated showers along some of
the windward coasts and slopes of the islands this morning. The
trade winds are expected to remain weak enough to allow local
afternoon sea breezes to become established over most islands.
These sea breezes may cause low clouds and a chance of showers to
develop over the interior sections of some of the islands later
today. Brief periods of MVFR conditions may occur along some
windward sections of the state this morning, and across the
interior terrain of some of the islands this afternoon.
Otherwise, expect primarily VFR conditions to prevail across the
state today.

As we head into this evening, local nighttime land breezes may
again develop over most islands. However, later tonight and
Sunday, the winds will begin to shift out of the southwest, and
gradually strengthen as a strong cold front approaches the region
from the northwest. The strengthening southwesterly winds may
start to bring increasing cloud cover and showers up toward Kauai
by early Sunday.

No AIRMETs are currently in effect, and none are anticipated
through this evening.

&&

.MARINE...
In summary, an active winter pattern this holiday weekend, with
giant surf today and tonight, and a potent cold front moving down
the island chain late Sunday into Monday.

The largest NW swell of the winter season so far will rapidly
build through the day, with peak surf heights of 40 to 50 feet
(with locally higher waves) expected along exposed shores, where
a High Surf Warning is in effect. Based on overnight observations
from offshore NDBC buoys 51001/51101 NW of Kauai (now at 19 feet
19 seconds), the expectation is that the peak of the swell will
occur on Kauai around late morning, on Oahu shortly after mid-
day, and mid- to late-afternoon on Maui. A High Surf Advisory has
been issued for exposed N and W facing shores of the Big Island
for surf building this afternoon, and peaking overnight. The
swell will gradually diminish from NW to SE on Sunday and Sunday
night, but a new NW swell arriving into Monday will likely push
surf to warning levels once again, with peak surf heights lower
than today's swell.

The giant NW swell, and today's increased E/SE winds, have prompted
a Small Craft Advisory for all waters as seas build rapidly, and
a Marine Weather Statement due to the potential for surges and
significant wave action in and near exposed harbors. Due to the
period and size of the NW swell, some (much reduced) swell may
wrap into select S and E facing shores.

A surface ridge N of Kauai has strengthened overnight, while a
trough NW of Kauai has all but dissipated, leading to increased E
to SE winds, with locally strong winds expected through this
afternoon over some Maui and Big Island waters. The ridge will
move back S (and over the islands) tonight as what is expected to
be a vigorous cold front rapidly approaches from the NW. This
front will force the ridge to move SE of the Big Island Sunday and
Sunday night, leading to a brief period of light to moderate S to
SW winds, until the front's passage ushers in near gale force N
winds Sunday night. A strong high to the NW of the islands will
continue to support strong to near-gale force NE winds over most
waters into Monday as the front stalls over the eastern islands.
As the front stalls, it will continue to act as a focus for shower
development as it transitions to a trough, and then moves back
toward the smaller islands as trade winds gradually return Tuesday
and Wednesday.

The front will initially bring the potential for locally heavy
showers and maybe a thunderstorm as it moves relatively quickly
through Kauai and Oahu, and then slows over Maui County and the
Big Island. A strong trough aloft is expected Monday and Tuesday,
maintaining (and maybe even increasing) the potential for heavy
showers and thunderstorms along the boundary.

&&

.HFO WATCHES/WARNINGS/ADVISORIES...
High Surf Warning until 6 AM HST Sunday for Niihau-Kauai
Windward-Kauai Leeward-Waianae Coast-Oahu North Shore-Oahu
Koolau-Olomana-Molokai-Maui Windward West-Maui Central Valley-
Windward Haleakala.

High Surf Advisory from noon today to 6 PM HST Sunday for Kona-
Big Island North and East-Kohala.

Small Craft Advisory until 6 PM HST Sunday for all Hawaiian
waters except Maalaea Bay-

Small Craft Advisory until 6 PM HST this evening for Maalaea Bay.

&&

DISCUSSION...Gibbs
AVIATION...Houston
MARINE...Birchard