000 AXPZ20 KNHC 092103 TWDEP Tropical Weather Discussion NWS National Hurricane Center Miami FL 2205 UTC Thu Jul 9 2020 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. ...SPECIAL FEATURES... Tropical Storm Cristina is centered near 17.9N 111.1W at 09/2100 UTC moving WNW at 11 kt. Estimated minimum central pressure is 993 mb. Maximum sustained wind speed is 60 kt with gusts to 75 kt. Numerous moderate and scattered strong convection is noted within 180 nm in the SE semicircle and 45 nm in the NW semicircle. Scattered moderate and isolated strong convection is noted elsewhere within 390 nm in the SE semicircle and 90 nm in the NW semicircle of Cristina. A far outer band has become less defined with still isolated to scattered moderate convection found between 450 nm and 720 nm in the E and S quadrants. Cristina is forecast to strengthen to a hurricane early Fri morning, then weaken back to a tropical storm early Sat, and continue to move WNW, well offshore of Mexico. Please read the latest NHC Public Advisory at: https://www.nhc.noaa.gov/text/MIATCPEP5.shtml and Forecast/ Advisory at https://www.nhc.noaa.gov/text/MIATCMEP5.shtml for more details. ...TROPICAL WAVES... A tropical wave is along 84W, N of 03N into western Panama and the western Caribbean Sea, moving W at 15 to 20 kt. Scattered moderate and isolated strong convection is noted from 06N to 11N between 83W and 91W. A tropical wave is along 96W, N of 04N into southern Mexico near the Tehuantepec region, moving W at 15 to 20 kt. Scattered moderate and isolated strong convection is noted from 05N to 12N between 93W and 101W. A tropical wave is along 123W from 03N to 19N, moving W at 10 to 15 kt. Scattered moderate convection is from 11N to 14N between 121W and 123W. ...INTERTROPICAL CONVERGENCE ZONE/MONSOON TROUGH... The monsoon trough axis extends from northern Colombia near 11N73W to 09N89W to 07N96W to 11N103W, then resumes W of Cristina near 16N116W to low pressure near 16N121.5W to 11N130W to 09N140W. Scattered moderate and isolated strong convection is noted from 11N to 13N between 123W and 129W, and within 120 nm either side of the axis between 130W and 140W. OFFSHORE WATERS WITHIN 250 NM OF MEXICO... Please see the Special Features section for information on Tropical Storm Cristina. Outer bands of convection associated with Cristina will pass through the offshore waters, with squalls and heavy rainfall. A ridge across the waters W of Baja California is retracting westward as Cristina moves into the area. The ridge will continue to support gentle to moderate NW-N winds. Expect periods of fresh southerly winds over the northern Gulf of California through Fri as the pressure gradient tightens across the area, then again early next week. Winds will increase to fresh to strong Tue and Tue night. Mainly gentle to moderate southerly winds are expected elsewhere across the Gulf of California. OFFSHORE WATERS WITHIN 250 NM OF CENTRAL AMERICA, COLOMBIA, AND WITHIN 750 NM OF ECUADOR... Moderate to fresh NE to E winds are expected in the Papagayo region during the next several days, briefly reaching fresh to strong this evening around sunset. Moderate to fresh SW winds will prevail over the waters S of 10N through Sat, and then again early next week. Seas will be mainly 4 to 7 ft in S-SW swell through Mon. REMAINDER OF THE AREA... Please see the Special Features section for information on Tropical Storm Cristina. A surface ridge dominates the northern waters, with moderate to fresh N-NE winds across the area. Earlier altimeter data indicated lingering 8 ft seas in mixed NE and SW swell, while an observation from ship D5QV7 this morning reported 8 ft seas across the W-central waters N of the monsoon trough. This area of seas will contract and decay through the next couple of days. A 1008 mb low pressure area is analyzed along the monsoon trough near 16N121.5W. Associated convection has decreased, however a lingering area of fresh winds and 8 ft seas are found on the SW and NW sides of the low. The low will dissipate on Fri as Cristina moves closer to it. Any remnant seas will merge into the broader SW monsoonal flow and fresh swell SE-S of Cristina. An area of low pressure is forecast to form south of the Gulf of Tehuantepec in a couple of days. Environmental conditions are expected to be conducive for development, and a tropical depression could form early next week while the system moves westward well south of the coast of Mexico. As Cristina moves W-NW into the ridge, the pressure gradient over the NW waters will tighten this weekend into early next week resulting in a large area of fresh to strong N-NE winds and building seas, even though Cristina will be weakening by then. $$ Lewitsky