000 AXPZ20 KNHC 070321 TWDEP Tropical Weather Discussion NWS National Hurricane Center Miami FL 0405 UTC Thu Jul 7 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 0000 UTC surface analysis and satellite imagery through 0300 UTC. ...SPECIAL FEATURES... Hurricane Blas is centered near 15.2N 125.4W at 0300 UTC Jul 07. moving west-northwest or 290 deg at 10 kt. The maximum sustained winds continue at 110 kt with gusts to 135 kt. Estimated minimum central pressure is 956 mb. Latest satellite imagery shows quite an impressive symmetric ring of very cold top convection surrounding the distinct eye of Blas. The measured eye diameter is 20-25 nm. Numerous strong convection is within 90 nm of the eye in the south quadrant. Scattered strong convection is noted elsewhere within 75 nm of the eye. Scattered moderate to isolated strong convection is noted elsewhere from 10N to 15N between 105W and 108W. Blas is still forecast to begin to weaken late tonight into Thursday morning as it moves across lowering sea surface temperatures. The trend as indicated by model guidance is for it to continue to gradually weaken over the next 48 hours. Refer to latest NHC public advisory under AWIPS/WMO headers MIATCPEP3/WTPZ33 KNHC and the full forecast advisory under AWIPS/WMO headers MIATCMEP3/WTPZ23 KNHC for additional details. Recently formed Tropical Depression Four-E is centered near 12.4N 109.9W at 0300 UTC Jul 07 moving west-northwest at 285 deg at 7 kt. The maximum sustained winds are 30 kt with gusts to 40 kt. Estimated minimum central pressure is 1006 mb. Latest satellite imagery shows the depression has a well-defined circulation, and convection is exhibiting more of a curved band pattern primarily in the northeast semicircle. The observed convection consists of scattered moderate to isolated strong within 120 nm of the center in the north quadrant, and also from 10N to 15N between 105W and 108W. Favorable upper level conditions are forecast to allow for the depression to strengthen to a tropical storm by early Thursday afternoon near 12.3N 111.4W, and continue to gradually strengthen through Friday as it moves in a westward direction. Refer to latest NHC public advisory under AWIPS/WMO headers MIATCPEP3/WTPZ33 KNHC and the full forecast advisory under AWIPS/WMO headers MIATCMEP4/WTPZ24 KNHC for additional details. ..INTERTROPICAL CONVERGENCE ZONE/MONSOON TROUGH... The monsoon trough axis extends from 08N78W to 09N95W to 11N106w. It resumes from southwest of Blas to 11N137W the continues as ITCZ axis to beyond 11N140W. Scattered moderate to strong convection is within 60 nm of the axis between 97W and 103W. Scattered moderate to isolated strong convection is within 120 nm s of the trough axis between 93W and 97W, and between 103W and 105W. ...DISCUSSION... North of 15N east of 120W: A ridge extending from the north central Pacific to S of the Baja California peninsula near 19N 110W will maintain gentle to moderate winds across the region north of 20N through late week. The Ascat pass from 1654Z from Wednesday afternoon captured strong southeast winds over the northern Gulf of California. These winds are forecast to diminish on Thursday as the pressure gradient between the Baja California thermal trough, and high pressure ridging west of Baja California slackens. Moderate southerly flow will continue across the central Gulf of California through early Thursday. On Thu winds and seas will increase N of 10N and west of 110W as the coverage of showers and thunderstorms increases in association with the intensifying Tropical Depression Four-E. South of 15N east of 120W: Aside from newly formed Tropical Depression Four-E mentioned above, the main issues will be scattered showers and thunderstorms along the monsoon trough and off the coast particularly at night. In addition, moderate to fresh gap wind flow will begin to pulse through the Gulf of Papagayo during overnight and early morning hours through early Sunday. West of 120W: The remnant low of Agatha is centered at 21N138W at 0000 UTC Jul 07, with a pressure of 1014 mb. Although there is currently no associated deep convection, fresh winds were suggested by the 1838 UTC Ascat to be within 120 nm of the low in the northern semicircle. The low is forecast to continue weakening into a trough through the next 36 to 48 hours as winds diminishing below 20 kt and seas subside below 8 ft through 72 hours as the remnants move west. See the special features section above for details on Hurricane Blas and on Tropical Depression Four-E. Tropical storm force and greater conditions will shift WNW across the central waters surrounded by a large area of seas 8 ft or greater that will expand outward across almost the entire area through Friday. $$ Aguirre