000 AXPZ20 KNHC 021602 TWDEP Tropical Weather Discussion NWS National Hurricane Center Miami FL 1354 UTC Sun Jul 2 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 1200 UTC surface analysis and satellite imagery through 1600 UTC. ...TROPICAL Lows and WAVES... A tropical wave extends N from 09N89W to 18N88W. The wave has been moving W around 15 kt over the past 24 hours. The wave has been triggering convection over Central America, but currently possesses no significant convection. A tropical wave is analyzed from 05N104W to 16N105W with a 1008 mb surface low in phase with the wave near 11N105W. The wave and low have been moving W at 10 to 15 kt during the past 24 hours. Scattered moderate isolated strong convection is currently observed within 360 nm of the center. Although the convection occasionally organizes in bands, the bands have not been persistent. The low is forecast to move W-NW at around 10 kt during the next few days. A 1009 mb low pressure center is analyzed along the monsoon trough at 10N120W. Scattered moderate and isolated strong convection is present within 120 nm of a line from 07N120W and 10N118W. ...INTERTROPICAL CONVERGENCE ZONE/MONSOON TROUGH... The monsoon trough reaches from 08N81W to 10N90W to 13N98W to 1008 mb low pressure centered near 11N105W to 12N114W to 1009 mb low pressure centered near 10N120W to 08N123W. The ITCZ continues from 08N123W to 09N135W, then resumes from 08N137W to beyond 07N140W. Except as mentioned with the surface lows and tropical waves, numerous moderate and scattered strong convection is present within 120 nm of 14N96W, from 06N to 09N between 126W and 131W and from 02N to 07N between 78W and 84W. Scattered moderate and isolated strong convection is taking place within 90 nm of a line from 04N89W to 10N94W. A surface trough extends from 06N137W to 13N134W. Scattered moderate and isolated strong convection is found from 10N to 13N between 130W and 134W. Scattered moderate convection is seen from 03N to 07N between 136W and 140W. ...DISCUSSION... OFFSHORE WATERS WITHIN 250 NM OF MEXICO... A WNW to ESE oriented ridge axis extends into the area from 21N120W to 20N112W. Moderate to locally fresh NW winds and 4 to 7 ft seas, are forecast W of the Baja Peninsula this morning, except for a round of long period NW swell that will bring 7 to 9 ft seas to the waters N of 27N between 117W and 127W. The pressure gradient will relax as the high to the NW weakens during the next few days. Gentle to moderate NW breezes and 3 to 6 ft seas are forecast W of Baja for the remainder of this week. Moderate cyclonic flow is expected across the waters between 98W and 108W through early Mon in association with a surface low passing to the S of the offshore waters. Gulf of Tehuantepec...Strong north to northeast nocturnal drainage flow will continue southward into the gulf to as far S as 14N between 95W and 97W each night this week. Gulf of California...A surface low is currently located over SE California in the thermal trough extending N from Baja California Norte. Fresh to locally strong SE to S winds are expected to the N of 30.5N today with seas building to 6 ft in the open fetch waters. Gentle to moderate southerly flow is expected elsewhere. The low and through will weaken later today and tonight and allow winds and seas to abate. Otherwise, light to gentle winds are forecasted over the Gulf of California through mid week. OFFSHORE WATERS WITHIN 250 NM OF CENTRAL AMERICA, COLOMBIA, AND WITHIN 750 NM OF ECUADOR... Gulf of Papagayo...Strong NE to E flow and seas to 7 ft are expected today and tonight, then fresh nocturnal NE-E winds are forecast this week with seas building to 6 ft. Gentle to moderate S to SW winds are forecast elsewhere this week with 3 to 6 ft seas prevailing through Wednesday, primarily due to cross-equatorial SW swell. The long period SW swell will cause seas W of Ecuador to build to above 8 ft by Thursday night. REMAINDER OF THE AREA... See tropical low and waves paragraph above for details on these features. A NW to SE oriented ridge extends across the area from 32N136W to 20N112W. Fresh NW to N winds are expected to the N of 30N and E of 125W today with 7-9 ft seas prevailing. Moderate anticyclonic flow is forecast elsewhere to the W of 120W, with 4-6 ft seas expected. Long period SW swell, in the form of 7-9 ft seas, are currently present across the tropical waters from 04N to 08N between 102W and 115W. Seas will subside to below 8 ft tonight as the swell decay. $$ CAM