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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.

Securite

Pacific N of 30n and S of 67n E of a line from Bering Strait to 50n 160e

Synopsis valid 1200 UTC Aug 19. 24 hour forecast valid 1200 UTC Aug 20. 48 hour forecast valid 1200 UTC Aug 21.

.Warnings.

...Storm Warning... .Low 53n146w 976 mb moving se 15 kt. Front extends from 54n145w to 53n139w to 47n134w. Within 240 nm W and SW quadrants winds 35 to 50 kt. Seas 18 to 24 ft. Elsewhere over waters within 420 nm W semicircle...within 240 nm NE and E of the front...and from 36n to 47n between 137w and 165w winds 25 to 40 kt. Seas 12 to 18 ft. .24 hour forecast low 51n135w 985 mb. Within 420 nm S and 480 nm SW quadrants winds 30 to 40 kt. Seas 18 to 24 ft. Elsewhere within 480 nm S and 540 nm W and NW quadrants...and from 37n to 44n between 133w and 165w winds 20 to 30 kt. Seas 12 to 18 ft. .48 hour forecast low 49n128w 1004 mb. Within 480 nm S and SW quadrants winds to 25 kt. Seas 10 to 16 ft.

...Ashfall advisory... .Okmok Volcano about 65 nm SW of Dutch Harbor Alaska is erupting and emitting volcanic ash. Volcanic ash is falling and may be reaching the surface in the vicinity of Umnak Island and in an area within 215 nm S semicircle of Umnak Island.

.Synopsis and forecast.

.low 47n171w 1003 mb moving E 20 kt. Within 180 nm N semicircle and within 480 nm S of a line from 48n164w to 43n177e winds 20 to 30 kt. Seas 8 to 12 ft. .24 hour forecast low dissipated and associated conditions diminished.

.Low 43n176e 1007 mb moving NE 30 kt. Within 360 nm S and 540 nm SW quadrants winds 20 to 30 kt. Seas 8 to 13 ft. .24 hour forecast low 47n169w 1003 mb. Front to extend from low to 40n176e. Within 540 nm S quadrant and within 300 nm S of the front winds 20 to 30 kt. Seas 8 to 14 ft. .48 hour forecast low 49n151w 1000 mb. Front to extend from low to 42n171w. Within 240 nm NE semicircle...480 nm S quadrant... and within 360 nm S of the front winds 20 to 30 kt. Seas 8 to 14 ft.

.Low 37n161e 1006 mb moving NE 25 kt. Over forecast waters within 360 nm S quadrant winds 20 to 30 kt. Seas 8 to 13 ft. .24 hour forecast low 40n173e 1010 mb. Front to extend from low to 37n160e. Within 300 nm S quadrant and 240 nm S of the front winds 20 to 30 kt. Seas 8 to 14 ft. .48 hour forecast low 43n169w 1011 mb. Front to extend from low to 36n160e. Within 300 nm S quadrant and within 240 nm S of the front winds 20 to 30 kt. Seas 8 to 13 ft.

.Low W of area 55n164e 1000 mb moving se 15 kt. Within 240 nm NE of a line from 55n170e to 52n178e winds to 25 kt. Seas to 9 ft. .24 hour forecast low 54n173e 1002 mb. Within 360 nm NE quadrant winds to 25 kt. Seas to 9 ft. .48 hour forecast low 54n176w 1002 mb. Within 360 nm SW quadrant winds to 25 kt. Seas to 8 ft.

.24 hour forecast from 31n to 37n between 120w and 125w area of NW winds to 25 kt. Seas to 8 ft. .48 hour forecast little change.

.within 180 nm se of a line from 50n137w to 47n141w and within 480 nm S of a line from 48n152w to 48n172w and N of 52n and W of 175e areas of dense fog occasionally reducing visibility below 1 nm. .24 hour forecast from 37n to 44n E of 128w and from 41n to 47n between 150w and 175w and also from 50n to 54n between 180w and 170e areas of dense fog occasionally reducing visibility below 1 nm. .48 hour forecast from 32n to 42n E of 130w and from 42n to 49n between 148w and 165w areas of dense fog occasionally reducing visibility below 1 nm.

.High 33n163w 1026 mb nearly stationary. .24 hour forecast high 33n163w 1027 mb. .48 hour forecast high 33n164w 1027 mb.

.high 33n153w 1026 mb nearly stationary. .24 hour forecast high 33n154w 1025 mb. .48 hour forecast high merged with high 33n164w.

.24 hour forecast high 44n168e 1014 mb. .48 hour forecast high 47n175e 1015 mb.

.Forecaster nolt. Ocean prediction center.

Tropical Prediction Center Miami FL E Pacific from the Equator to 30n E of 140w

Synopsis valid 1200 UTC Tue Aug 19. 24 hour forecast valid 1200 UTC Wed Aug 20. 48 hour forecast valid 1200 UTC Thu Aug 21.

.Warnings.

None.

.Synopsis and forecast.

.remnant low of Iselle 18n119w 1011 mb moving SW 10 kt. Within 180 nm NW semicircle winds 20 kt. Seas 8 ft. .24 hour forecast low 16n121w 1010 mb. Within 240 nm NW quadrant winds 20 kt. Seas 8 ft. .48 hour forecast low 15n124w 1010 mb. Little change in winds or seas.

.06 hour forecast S of 05n from 95w to 120 winds less than 20 kt. Seas 8 ft in S swell. .24 hour forecast S of 06n from 92w to 125w S winds to 20 kt. Seas to 9 ft in S swell. .48 hour forecast S of 08n between 91w and 120w S winds to 20 kt. Seas 8 to 10 ft in S swell.

.Remainder of area winds less than 20 kt. Seas less than 8 ft.

.Convection valid 1500 UTC Tue Aug 19. .intertropical convergence zone...10n85w to 09n100w to 12n120w to 09n140w. Scattered moderate to strong from 4n to 08n between 79w and 102w. Scattered moderate isolated strong within 90 nm S of axis from 125w and 130w.

$$ .Forecaster dgs. Tropical Prediction Center.