AXPZ20 KNHC 262132

Tropical Weather Discussion
NWS National Hurricane Center Miami FL
2205 UTC Wed Jul 26 2017

Tropical Weather Discussion for the eastern Pacific Ocean from the Equator to 32N, east of 140W. The following information is based on satellite imagery, weather observations, radar, and meteorological analysis.

Based on 1800 UTC surface analysis and satellite imagery through 2100 UTC.


Hurricane Hilary is centered near 16.7N 113.2W at 26/2100 UTC or about 415 nm SSW of the southern tip of Baja California moving W at 11 kt. Estimated minimum central pressure is 972 mb. Maximum sustained wind speed is 90 kt with gusts to 110 kt. Some slow weakening is forecast during the next 48 hours. Numerous moderate and scattered strong convection is within 90 nm of center. Scattered moderate convection is elsewhere within 210 nm of center. See latest NHC forecast/advisory under AWIPS/WMO headers MIATCMEP4/WTPZ24 for more details.

Tropical Storm Irwin is centered near 15.1N 122.8W at 26/2100 UTC or about 865 nm WSW of the southern tip of Baja California moving WSW at 6 kt. Estimated minimum central pressure is 996 mb. Maximum sustained wind speed is 45 kt with gusts to 55 kt. Irwin is forecast to move slowly with little change in strength during the next 48 hours. Numrerous moderate and isolated strong convection is from 15N to 18N between 122W and 125W. See latest NHC forecast/advisory under AWIPS/WMO headers MIATCMEP5/WTPZ25 for more details.


A tropical wave is along 102W/103W from 05N to 14N moving W at 10-15 kt. Isolated to scattered showers are near the wave axis.


The monsoon trough extends from to 09N84W to 08N95W to 09N102W to 12N108W. Scattered moderate isolated strong convection is N of 06N between 80W and 84W. Similar convection is from 07N to 09N between 90W and 93W, and from 08N to 10N between 90W and 95W. Scattered moderate convection is 08N to 11N between 104W and 110W.


OFFSHORE WATERS WITHIN 250 NM OF MEXICO... Gentle to moderate NW winds are expected to continue within 120 nm of the Baja California peninsula through Friday. Seas will maintain 6 to 8 ft as southerly swell associated with Hurricane Hilary will continue impacting the forecast zones offshore of Baja California through Friday then remain W of the area during the weekend. Gentle southerly flow will prevail in the Gulf of California, and moderate southerly flow across the northern Gulf of California.

Nocturnal fresh northerly winds are forecast across the Gulf of Tehuantepec through Friday morning with seas peaking at 8 ft briefly during the period of strongest winds. Hilary is currently south and midway between Revillagigedo Islands and Clarion Island. Fresh to strong winds and seas of at least 12- 13 ft are reaching those islands.

OFFSHORE WATERS WITHIN 250 NM OF CENTRAL AMERICA, COLOMBIA, AND WITHIN 750 NM OF ECUADOR... Across the Gulf of Papagayo, expect fresh winds each night with the assistance of the nocturnal drainage flow the next few days, occasionally building maximum seas to 7 ft in a mix of E wind waves and long period SW swell.

Gentle to moderate S to SW winds are expected the next few days. Long period cross-equatorial SW swell will continue to propagate into the forecast waters through Saturday, reaching the waters between Ecuador and the Galapagos Islands on Thursday with building seas of 8-9 ft.

REMAINDER OF THE AREA... High pressure is located N of the area with a ridge axis extending across the forecast waters N of 22N. The pressure gradient between this system and the active zone of tropical cyclone activity will maintain moderate to fresh N to NE winds W of 120W through Saturday. An altimeter pass indicated seas up to 9 ft associated with post-tropical cyclone Greg across the west- central waters from 17N to 21N W of 138W. At 26/2100 UTC...The Central Pacific Hurricane Center issued the last advisory on Greg. Long period cross equatorial 8-9 ft SW swell will spread across the waters S of 10N and E of 110W, persisting into the weekend.

$$ GR