000
AXPZ20 KNHC 240302
TWDEP

Tropical Weather Discussion
NWS National Hurricane Center Miami FL
0236 UTC Mon Jul 24 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 0000 UTC surface analysis and satellite imagery through
0130 UTC.

...SPECIAL FEATURES... 

The Eastern Pacific region remains very active with three
tropical cyclones: from east to west, Hilary, Irwin and Greg. 
Irwin and Hilary are forecast to become hurricanes, and Hilary a 
major hurricane. So far in July, five named storms have 
developed.

Tropical Storm Hilary is centered near 13.6N 103.5W, or about 330
nm SSE of Manzanillo, Mexico at 24/0300 UTC, moving WNW at 8 kt.
Estimated minimum central pressure is 999 mb. Maximum sustained 
winds have increased to 60 kt with gusts to 75 kt. Numerous 
moderate scattered strong convection are in a band 120 nm W 
semicircle of center. Scattered moderate isolated strong 
convection are elsewhere from 10N to 16N between 98W and 105W. 
Conditions are favorable for significant strengthening during the
next 24 to 48 hours, and Hilary will likely become a hurricane 
on Monday, and a major hurricane on Tuesday as it continues on a 
WNW track for the next couple of days. See the latest NHC 
forecast/advisory under AWIPS/WMO headers MIATCMEP4 WTPZ24 for 
more details.

Tropical Storm Irwin is centered near 14.9N 117.3W, or about 640
nm SW of the southern tip of Baja California at 24/0300 UTC, 
moving W at 7 kt with minimum central pressure of 1001 mb. 
Maximum sustained winds are 45 kt with gusts to 55 kt. Scattered 
moderate isolated strong convection are from 12N to 16N between 
113W and 118W. Irwin will remain in relatively close proximity to
Hilary the next few days. Gradual strengthening is expected 
during the next 48 hours, and Irwin is forecast to become a 
minimal hurricane on Tuesday. See the latest NHC 
forecast/advisory under AWIPS/WMO headers MIATCMEP5 WTPZ25 for 
more details.

Tropical Storm Greg is centered near 14.4N 131.4W at 24/0300 
UTC, moving W at 10 kt. Estimated minimum central pressure is 
1001 mb. Maximum sustained winds are 45 kt with gusts to 55 kt. 
Numerous moderate isolated strong convection are noted within 120
nm of the center. Greg is forecast to maintain its intensity for
another 24 hours, followed by gradual weakening due to the dry 
air, increasing shear, and cooler sea surface temperatures. Greg
is expected to weaken to a tropical depression on Wednesday, and
to a remnant low by Thursday. See the latest NHC 
forecast/advisory under AWIPS/WMO headers MIATCMEP2 WTPZ22 for 
more details.

...INTERTROPICAL CONVERGENCE ZONE/MONSOON TROUGH... 

The monsoon trough is analyzed E of the tropical cyclone activity
from 09N76W to 09N89W to 10N98W. The ITCZ extends from 10N134W 
to beyond 07N140W. Scattered moderate and isolated strong 
convection are noted from 05N to 10N E of 92W.

...DISCUSSION...

OFFSHORE WATERS WITHIN 250 NM OF MEXICO...

Gentle to moderate NW winds off the Baja California peninsula 
are expected to continue through mid-week, as high pressure 
remains centered N of the area. Seas will remain 4 to 7 ft in a 
mix of long period north and southwesterly swell. Gentle 
southerly flow will generally prevail in the Gulf of California, 
except for moderate southerly flow over the northern Gulf. 

Moderate E to SE winds are expected across most of the area 
between just west of Tehuantepec and Acapulco through early Mon.
Nocturnal fresh northerly winds are forecast over the Gulf of 
Tehuantepec Tuesday through Thursday nights. T.S. Hilary is 
expected to impact the offshore waters within 250 nm of the coast
of the Mexican States of Chiapas and Oaxaca through tonight, 
then the offshore waters of Guerrero, Michoacan and Jalisco 
through Tue. Hilary is forecast to cross south of the 
Revillagigedo Islands on Wednesday as a major hurricane.

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 through the week, 
occasionally building max seas to near 8 ft in a mix of east wind
waves and long period southwest swell.

Gentle to moderate S to SW winds are expected across the forecast
zones. Long period cross-equatorial SW swell creating 5-7 ft 
seas will continue to propagate into the forecast waters through
mid week. Another set of cross-equatorial long period SW swell of
6 to 9 ft will reach the waters between Ecuador and the 
Galapagos Islands late Wednesday, and the coast of Central 
America on Thursday. 

REMAINDER OF THE AREA... 

High pressure is located north of area with a ridge axis that extends
across the forecast waters north of 20N. The pressure gradient 
between this system and an active zone of tropical cyclones between
12N and 20N will maintain fresh N to NE winds mainly west of 
125W through mid-week. Seas of 8 to 10 ft associated with T.S. 
Greg are already propagating across the waters N of 20N W of 
130W. Northerly swell in the form of 7-8 ft seas will propagate S
of 32N between 125W and 135W the next two days. By Thursday
night, cross equatorial southwesterly swell of 8 to 9 ft will
spread over the waters south of 10N and east of 110W, persisting
into next weekend. 

$$
Latto