Tropical Storm Jova Forecast Discussion Number 1

By Newsroom America Feeds at 11 Aug 2017

Issued at 900 PM MDT Fri Aug 11 2017 000 WTPZ42 KNHC 120234 TCDEP2 Tropical Storm Jova Discussion Number 1 NWS National Hurricane Center Miami FL EP122017 900 PM MDT Fri Aug 11 2017 The mid-level remnants of Atlantic Hurricane Franklin moved across Mexico during the past day or so and induced a surface circulation early this morning near the southwest coast of Mexico. While earlier it was difficult to see a well-defined center, satellite images suggest that the multiple swirls seen in visible imagery during midday have consolidated, with enough convection remaining to classify the system as a tropical cyclone. The initial wind speed is 35 kt based on data from ship WDF4764 and a central pressure estimate of 1003 mb, making this system the tenth tropical storm of the season. Although this is the first tropical storm to form in the basin in about 3 weeks, the eastern Pacific is still way ahead of schedule since the average tenth tropical storm forms on August 31. Jova is over very warm water but is moderately sheared from the northeast due to the large high over Mexico. The storm has about a day to potentially intensify before a combination of cooler waters and increasing northeasterly shear likely start a weakening trend. Most of guidance respond to this environment by showing little change tomorrow, and a slow weakening starting by Sunday. Jova is forecast to become a remnant low by Monday due to marginal water temperatures and continued entrainment of dry stable air. The official forecast is close to a blend of SHIPS/LGEM in the short term, and the intensity consensus in the long term. The initial motion is 285/12. A mid-level ridge building westward across the eastern Pacific should cause Jova to turn westward by late tomorrow, and continue that general motion until dissipation. Model guidance is in pretty good agreement for a first advisory, so the official forecast is close to the model consensus. Note that since advisories were not continuous from the Atlantic basin to the Pacific basin, the cyclone is given a new eastern Pacific name, per WMO RA-IV operational protocols. FORECAST POSITIONS AND MAX WINDS INIT 12/0300Z 19.3N 109.8W 35 KT 40 MPH 12H 12/1200Z 19.7N 111.6W 40 KT 45 MPH 24H 13/0000Z 19.9N 113.9W 40 KT 45 MPH 36H 13/1200Z 20.1N 116.2W 35 KT 40 MPH 48H 14/0000Z 20.3N 118.6W 30 KT 35 MPH...POST-TROP/REMNT LOW 72H 15/0000Z 20.5N 123.5W 20 KT 25 MPH...POST-TROP/REMNT LOW 96H 16/0000Z...DISSIPATED $$ Forecaster Blake


[D] [Digg] [FB] [R] [SU] [Tweet] [G]