je.st
news
Tropical Storm Lorena Forecast Discussion Number 4
2019-09-18 10:57:26| National Hurricane Center (East Pacific)
Issued at 400 AM CDT Wed Sep 18 2019 ZCZC MIATCDEP5 ALL TTAA00 KNHC DDHHMM Tropical Storm Lorena Discussion Number 4 NWS National Hurricane Center Miami FL EP152019 400 AM CDT Wed Sep 18 2019 Satellite imagery and a 0352 UTC ASCAT-B scatterometer pass indicate that Lorena has strengthened this morning. Subjective and objective intensity estimates as well as the scatterometer overpass support increasing the initial intensity to 50 kt for this advisory. Although the cloud pattern has improved a bit during the past several hours, moderate northeasterly shear still appears to be impinging on the northern portion of the cyclone. The statistical-dynamical GFS and ECMWF Decay SHIPS intensity models both indicate that this upper wind pattern will linger the next couple of days. Consequently, gradual strengthening is expected which is consistent with the aforementioned DSHPS and the NOAA HFIP HCCA intensity consensus model, and Lorena is forecast to become a hurricane in 48 hours. Beyond that period, weakening should commence as the cyclone traverses decreasing oceanic sea surface temperatures and moves within increasing westerly shear. An alternative intensity forecast is for Lorena to dissipate if the center moves onshore in southwestern Mexico which the ECMWF is showing. The initial motion is estimated to be northwestward, or 310/12 kt. A deep-layer ridge extending westward over Mexico from the western Gulf of Mexico is forecast to steer Lorena toward the northwest with a slight reduction in forward speed through day 5. This persistent synoptic steering flow should bring the cyclone near the southwestern coast of Mexico Thursday and Friday. The NHC forecast is a little faster than the previous one and follows the NOAA HFIP HCCA consensus which keeps the cyclone offshore. Key Messages: 1. Lorena is forecast to cause heavy rain over portions of the Mexican states of Guerrero, Michoacan, Colima, and Jalisco during the next few days. This rainfall may produce life-threatening flash flooding and mudslides. 2. Tropical storm conditions are expected along a portion of the southwestern coast of Mexico by late Wednesday. FORECAST POSITIONS AND MAX WINDS INIT 18/0900Z 16.1N 103.0W 50 KT 60 MPH 12H 18/1800Z 17.4N 104.1W 55 KT 65 MPH 24H 19/0600Z 18.5N 104.9W 60 KT 70 MPH 36H 19/1800Z 19.4N 105.5W 60 KT 70 MPH 48H 20/0600Z 20.1N 106.4W 65 KT 75 MPH 72H 21/0600Z 21.5N 108.7W 65 KT 75 MPH 96H 22/0600Z 23.2N 111.1W 55 KT 65 MPH 120H 23/0600Z 25.6N 112.9W 45 KT 50 MPH $$ Forecaster Roberts NNNN
Tags: number
discussion
storm
tropical
Category:Transportation and Logistics
Latest from this category |
All news |
||||||||||||||||||
|
|||||||||||||||||||