TROPICAL STORM CARLOS ADVISORY NUMBER 4
WIKI-HURRICANES FORECAST CENTER
1000AM CDT THU JUN 11 2015
...TROPICAL STORM CARLOS BECOMES THE THIRD TROPICAL STORM OF THE 2015 PACIFIC HURRICANE SEASON... ...GRADUAL INTENSIFICATION ANTICIPATED...
SUMMARY OF 1000AM CDT...1500 UTC...INFORMATION
LOCATION... 13.5N 100.7W
ABOUT 240MI... 385KM SSW OF ACAPULCO, MEXICO
MAXIMUM SUSTAINED WINDS...35 KT...40 MPH...65 KM/H
MINIMUM BAROMETRIC PRESSURE... 1000 MB...29.53 INCHES
PRESENT MOVEMENT...WNW AT 6 KT...7 MPH...11 KM/H
DISCUSSION AND 48-HOUR OUTLOOK
At 1000 am CDT, the center of Tropical Storm Carlos was located at 13.5N, 100.7W, or about 240 miles (385 km) south-southwest of Acapulco, Mexico. Maximum sustained winds were 35 knots (40 mph, 65 km/h), with higher gusts. The minimum barometric pressure was 1000 millibars (hPa; 29.53 inHg), and the system was moving west-northwest at 6 knots (7 mph, 11 km/h). Conditions are expected to be favorable over the next two days for gradual intensification as the storm nears the Mexican coastline.
Next complete advisory at 400 pm CDT.
TROPICAL STORM CARLOS DISCUSSION NUMBER 4
WIKI-HURRICANES FORECAST CENTER
1000 AM CDT THU JUN 11 2015
Satellite imagery over the last six hours indicates increased organization of spiral banding about the center as well as a developing symmetric central dense overcast. Convection has become more concentrated around the center, with microwave imagery from the 0935z F15 satellite pass indicating improving internal structure, though the deepest convection remains displaced southwest of the center. At 12z, subjective satellite intensity estimates from SAB were T2.5/35kt and T3.0/45kt from TAFB. However, taking into account these estimates and given the lackluster readings from the 0416z ASCAT pass, the intensity for this advisory has been conservatively set to 35 kt... making Carlos the third named tropical cyclone of this Pacific hurricane season.
The current intensity forecast for Carlos is on the high end of model forecasts given the currently favorable atmospheric conditions and the recent organization of Carlos' core. Wind shear is expected to remain low throughout the next 120 hours, and despite being climatologically cool in some areas due to the recent passage of Hurricane Blanca, SSTs are expected to remain sufficient for strengthening. The SHIPS intensity forecast notes a 54% chance of a 25 knot rapid intensification phase as a result of these favorable conditions, though Carlos is not expected to undergo rapid intensification at least this morning and early afternoon as the displaced convection noted on microwave imagery is not a convective configuration conducive for rapid intensification. The proximity of Carlos to Mexico over the next few days will ultimately be the largest factor determining Carlos' intensity. Though conditions are favorable offshore, if Carlos traverses too close to Mexico, land interaction may disrupt the system's circulation. Furthermore, if Carlos' circulation is sufficiently large enough, the storm may pull dry air from the central mountains of Mexico, which may help to put a cap or weaken Carlos' intensity. The current forecast for Carlos depicts gradual strengthening out to 96 hours, after which the intensity is capped at 85 knots to take into account the proximity of land and lack of model support for anything stronger.
The current motion of Carlos is an uncertain 290/6, as Carlos appears to have slowed down over the last six hours due to the weak steering currents at play. Carlos appears to be beginning to make an anticipated northward turn which will allow for the ridge northwest of Carlos to strengthen later on. Models have been reaching a greater degree of consensus as to what the future track of Carlos will be, with models shifting away from a skid of the Mexican coastline to more of a close pass that should bring Carlos to about 150 miles of the Mexican coastline. The latest WHFC track forecast has been shifted further west and southward to reflect these changes. Some GFS ensembles continue to show a landfall, though this scenario is becoming less apparent, with the ECMWF, HWRF, and primary GFS model showing no landfall. Carlos should begin a slow northward crawl over the next two days before accelerating west-northwestward under the influence of an intensifying ridge after 48 hours. After 96 hours, Carlos may begin a slight curve northwestward along the southwestern periphery of the ridge, though climatology would favor a more westerly path. The current forecast guidance is near the track consensus.
INIT 11/1500Z 13.5N 100.7W 35KT 40MPH
12HR 12/0600Z 13.8N 100.9W 45KT 50MPH
24HR 12/1800Z 14.2N 100.8W 50KT 60MPH
36HR 13/0600Z 14.5N 100.7W 60KT 70MPH
48HR 13/1800Z 14.9N 100.7W 70KT 80MPH
72HR 14/1800Z 15.7N 101.3W 75KT 90MPH
96HR 15/1800Z 16.5N 103.8W 85KT 100MPH
120HR 16/1800Z 17.6N 106.2W 85KT 100MPH