000 AXPZ20 KNHC 231004 TWDEP Tropical Weather Discussion NWS National Hurricane Center Miami FL 1005 UTC Tue Aug 23 2016 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 0600 UTC surface analysis and satellite imagery through 0900 UTC. ...SPECIAL FEATURES... The center of Tropical Depression Kay at 23/0900 UTC is near 22.0N 119.3, or about 525 nm to the west of the southern tip of Baja California. Kay is moving westward, or 275 degrees, 7 knots. The estimated minimum central pressure is 1006 mb. The maximum sustained wind speeds are 30 knots with gusts to 40 knots. The latest satellite imagery shows that the overall cloud pattern and convective structure of Kay continue to weaken. The cold cloud tops continue on the warming trend. Only scattered moderate convection is within 90 nm of the center in the northwestern quadrant. Kay is forecast to weaken to a post- tropical remnant low in 24 hours on Wednesday, and then to dissipate early on Friday. Please read the latest NHC forecast/ advisory under AWIPS/WMO headers MIATCMEP2/ WTPZ22 KNHC for more details, and the latest public advisory MIATCPEP2/WTPZ32 KNHC, for more details. A tropical wave is along 99W from 18N southward, and moving westward 10 to 15 knots. A 1009 mb low pressure center is along the wave near 11N. Each feature is part of a broad area of low pressure. A second tropical wave is along 94W from 21N southward. Convective precipitation: scattered moderate to isolated strong from 09N to 16N between 94W and 107W. Global model guidance indicates that atmospheric conditions are favorable for development of this system through the next 48 hours. ...TROPICAL WAVES... .TROPICAL WAVE ALONG 94W S OF 21N AND TROPICAL WAVE ALONG 99W S OF 18N. LOW PRES NEAR 11N99W 1009 MB. SCATTERED MODERATE ISOLATED STRONG FROM 09N TO 16N BETWEEN 94W AND 107W. .LOW PRES NEAR 09N114W 1008 MB AND TROPICAL WAVE ALONG 119W S OF 14N...SCATTERED MODERATE ISOLATED STRONG FROM 07N TO 14N BETWEEN 116W AND 122W. ...INTERTROPICAL CONVERGENCE ZONE/MONSOON TROUGH... Monsoon trough extends from 07N78W to 09N94W to low pressure near 09N114W 1008 mb to 08N121W to 10N131W. The ITCZ continues from 10N131W beyond 08N140W. Convective precipitation: scattered moderate to isolated strong within 90 nm to the north of the monsoon trough from 79W eastward, WITHIN 90 NM N OF MONSOON TROUGH E OF 79W...WITHIN 180 NM N OF MONSOON TROUGH AND WITHIN 120 NM S OF MONSOON TROUGH BETWEEN 108W AND 113W...AND WITHIN 60 NM S OF MONSOON TROUGH BETWEEN 124W AND 127W. ...DISCUSSION... OFFSHORE WATERS WITHIN 250 NM OF MEXICO... Tropical Storm Kay has moved west of the forecast area. Light to moderate winds prevail over much of the area in a relatively weak pressure pattern, which will persist into early next week. Combined seas of 4 to 6 feet will subside gradually during the next few days. The Gulf of Tehuantepec: The tight gradient behind the tropical wave along 98W in combination with nocturnal drainage flow into the Gulf will bring north to northeast winds of 20 to 25 knots into the Gulf with seas building to 8 ft beginning on Tuesday morning. These winds will briefly diminish to 15 to 20 kt on Tuesday afternoon, then start up again late Tuesday night into Wednesday with seas building to 10 ft Wednesday morning. OFFSHORE WATERS WITHIN 250 NM OF CENTRAL AMERICA, COLOMBIA, AND WITHIN 750 NM OF ECUADOR... Winds will pulse into the Gulf of Papagayo during the next few nights...peaking near 25 kt during the late night and early morning hours and weakening to 20 kt during the late afternoon and early evening hours. Elsewhere, Light to moderate winds will prevail on either side of the monsoon trough with seas in the 4 to 6 foot range. ELSEWHERE... Low pressure of 1008 mb along the monsoon trough near 10N112W. Latest satellite imagery shows scattered moderate isolated strong convection is within 60 nm of the low in the southeast quadrant. The Ascat pass from 1728Z Monday afternoon showed a swath of strong south to southwest winds south of the low, and within the monsoon trough region from 07N to 09N between 110W and 115W. Seas of 6 to 8 ft are associated with these winds. This low is forecast to move in a general west-northwest direction to near 10N115W by early Tuesday evening, and to near 11N121W by early Wednesday evening with some potential for gradual development. The strong south to southwest winds to its south will expand westward as the low with seas possibly reaching near 10 ft late Tuesday night or on Wednesday. Elsewhere, weak high pressure of 1018 mb is centered near 32N126W. The resulting weak pressure gradient is maintaining generally light to gentle winds with sea heights in the range of 4 to 6 feet, except near the vicinity of Kay where the gradient between the cyclone and the ridge is keeping winds of higher speeds, in the moderate to fresh range with seas of 5 to 8 ft there. These winds and seas will shift westward as near the cyclone as it weakens to a remnant low over the next couple of days. $$ mt