The High Seas Forecast for the South Pacific

Severe Weather and Heavy Rainfall Potential for the Plains; Coastal Low Across the mid-Atlantic

An upper trough and frontal boundary will focus showers and thunderstorms across portions of the Plains through early Monday; A few severe thunderstorms along with heavy rainfall are expected. Meanwhile, low pressure off the Southeast Coast will bring inclement weather across the mid-Atlantic coast through Monday. This system is forecast to meander off the coast then track inland early this week. Read More >

565 FZPS40 PHFO 201533 HSFSP HIGH SEAS FORECAST NATIONAL WEATHER SERVICE HONOLULU HI 1730 UTC SAT SEP 20 2025 SUPERSEDED BY NEXT ISSUANCE IN 6 HOURS SEAS GIVEN AS SIGNIFICANT WAVE HEIGHT...WHICH IS THE AVERAGE HEIGHT OF THE HIGHEST 1/3 OF THE WAVES. INDIVIDUAL WAVES MAY BE MORE THAN TWICE THE SIGNIFICANT WAVE HEIGHT. THIS HIGH SEAS FORECAST USES 1-MINUTE AVERAGE WINDS WHICH MAY BE HIGHER THAN 10-MINUTE AVERAGE WINDS. SECURITE SOUTH PACIFIC EQUATOR TO 25S BETWEEN 120W AND 160E SYNOPSIS VALID 1200 UTC SEP 20 2025. 24 HOUR FORECAST VALID 1200 UTC SEP 21 2025. 48 HOUR FORECAST VALID 1200 UTC SEP 22 2025. .WARNINGS. .NONE. .SYNOPSIS AND FORECAST. .FRONT 25S156W 22S156W 13S161W THENCE TROUGH 07S171W 05S175E. TROUGH AND FRONT MOVING ESE SLOWLY. WINDS 20 TO 30 KT S OF 22S BETWEEN 161W AND 147W. SCATTERED MODERATE TSTMS WITHIN 240 NM E OF FRONT S OF 18S. ISOLATED MODERATE TSTMS ELSEWHERE FROM 07S TO 03S BETWEEN 172E AND 177E. .24 HOUR FORECAST FRONT 25S157W 19S158W THENCE TROUGH 13S160W 06S174W. ASSOCIATED WINDS MOVED S OF AREA. .48 HOUR FORECAST FRONT 25S151W 20S155W THENCE TROUGH 12S159W 06S170W. .FRONT 20S120W 17S127W 16S138W NEARLY STATIONARY. .24 HOUR FORECAST WEAK FRONT 16S120W 14S134W 15S145W. .48 HOUR FORECAST FRONT WEAKENED TO TROUGH 17S120W 12S140W. .TROUGH 09S168E 07S160E MOVING SW SLOWLY. ISOLATED MODERATE TSTMS FROM 10S TO 04S W OF 172E. .24 HOUR FORECAST TROUGH 13S163E 08S160E. .48 HOUR FORECAST TROUGH 14S163E 11S160E. .24 HOUR FORECAST NEW TROUGH 25S165E 17S160E. .48 HOUR FORECAST TROUGH 25S167E 17S167E. .24 HOUR FORECAST WINDS 20 TO 25 KT S OF 13S BETWEEN 171E AND 171W. .48 HOUR FORECAST WINDS 20 TO 25 KT S OF 12S BETWEEN 171E AND 167W. .WINDS 20 KT OR LESS OVER REMAINDER OF FORECAST AREA. .SEAS 2.5 TO 4 M S OF 16S E OF 178W. .24 HOUR FORECAST SEAS 2.5 TO 3 M S OF 14S BETWEEN 172E AND 166W...AND S OF 14S E OF 146W. .48 HOUR FORECAST SEAS 2.5 TO 4 M S OF LINE 25S171E 13S172E 12S167W 25S154W. .SEAS 2.5 M OR LOWER OVER REMAINDER OF FORECAST AREA. $$ .FORECASTER TROTTER. HONOLULU HI.