je.st
news
Tropical Storm ESTELLE Forecast Discussion Number 8
2016-07-17 10:47:48| National Hurricane Center (East Pacific)
Issued at 300 AM MDT SUN JUL 17 2016 000 WTPZ41 KNHC 170847 TCDEP1 TROPICAL STORM ESTELLE DISCUSSION NUMBER 8 NWS NATIONAL HURRICANE CENTER MIAMI FL EP062016 300 AM MDT SUN JUL 17 2016 A large increase in both the areal coverage and depth of the central convective cloud mass has occurred since the previous advisory due to the development of a irregularly shaped CDO. Cloud tops near the alleged center have been -80C and colder during the past couple of hours. Recent SSMI/S and AMSU microwave passes indicate that the low-level circulation center has become better defined, and has also moved closer to the strongest convection and farther into the CDO. As a result, satellite intensity estimates from TAFB and SAB have increased to a consensus T3.5/55 kt. However, UW-CIMSS ADT and NHC objective Dvorak estimates are only T2.8/41 kt and T3.0/45 kt, respectively. Given that the aforementioned microwave images still indicated some southward tilt to the mid-level center due to modest northerly vertical shear, the initial intensity has only been increased to 50 kt for this advisory. The initial motion estimate is westward or 280/08 kt. A motion between west and west-northwest is expected for the next 96 hours as Estelle moves along the southern periphery of a strong deep-layer to its north. After that time, a strong mid-latitude upper-level trough/low currently located near 25N/119W is forecast to dig southwestward and erode the ridge, allowing Estelle to turn northwestward into the developing weakness in the subtropical high. The new NHC model guidance remains tightly packed, and the official forecast track is just an update of the previous advisory track, and follows a blend of the GFS, ECMWF, and Florida State Superensemble (FSSE) models. Moderate northerly to northwesterly shear is forecast to affect Estelle for the next 36 hours, so only modest intensification is expected. After that, however, the vertical shear is forecast to decrease to around 5 kt through the end of the period, resulting in more substantial strengthening through 72 h while the cyclone remains over favorable SSTs. By 96 h, gradual weakening is forecast to ensue as Estelle begins to move over sub-25C ocean temperatures. The NHC intensity forecast is similar to the previous advisory, and remains above the model consensus IVCN and the SHIPS/LGEM models, but close to the FSSE intensity forecast. FORECAST POSITIONS AND MAX WINDS INIT 17/0900Z 16.2N 111.1W 50 KT 60 MPH 12H 17/1800Z 16.6N 112.2W 60 KT 70 MPH 24H 18/0600Z 17.1N 113.7W 65 KT 75 MPH 36H 18/1800Z 17.6N 115.3W 70 KT 80 MPH 48H 19/0600Z 17.8N 117.1W 75 KT 85 MPH 72H 20/0600Z 18.3N 121.1W 85 KT 100 MPH 96H 21/0600Z 18.9N 125.8W 70 KT 80 MPH 120H 22/0600Z 20.7N 131.1W 50 KT 60 MPH $$ Forecaster Stewart
Tags: number
discussion
storm
tropical
Category:Transportation and Logistics
Latest from this category |
All news |
||||||||||||||||||
|
|||||||||||||||||||