ZCZC MIATCDEP3 ALL TTAA00 KNHC DDHHMM HURRICANE CARLOS DISCUSSION NUMBER 13 NWS NATIONAL HURRICANE CENTER MIAMI FL EP032015 400 PM CDT SAT JUN 13 2015 Satellite images show that Carlos is becoming stronger. The eye is becoming better defined, with a more symmetric appearance on the latest infrared pictures. Radar data also shows a more complete eyewall, although it is still open on the north side at times. Dvorak estimates from TAFB/SAB support an intensity of 75 kt for the initial wind speed. Over the past 24 hours, Carlos has drifted northeastward toward a weakness in the mid-level ridge over Mexico related to a trough over the Gulf of Mexico. All models continue to insist that the ridge will strengthen soon, forcing Carlos more toward the west-northwest or northwest over the next couple of days. The ridge is expected to weaken again due to a trough over northwestern Mexico, which should cause Carlos to turn more to northwest by late Monday. However, since any significant westward motion has yet to materialize, the guidance continues to show a greater threat to Mexico, with many models now having a landfall within a few days time. Thus, the NHC forecast is moved to the right in agreement with the model consensus. Although the center is still offshore of Mexico through 36 hours, the hurricane-force wind radii are too close for comfort, and therefore the government of Mexico has issued a Hurricane Warning for a portion of the southwestern coast. Microwave data show that the low- and mid-level circulations of Carlos remain a little displaced from one another due to northeasterly shear. However, this shear is forecast to get rather light over the next 24 hours while the hurricane moves over waters near 30C. It appears that the environment overall is becoming more supportive of significant strengthening than earlier anticipated, assuming that Carlos moves as forecast and does not suffer from its own cold wake. This favorable environment is also reflected in the SHIPS rapid intensification index showing a 30 percent chance of a 30 kt increase over the next 24 hours. Thus, the NHC forecast is raised from the previous one, above most of the guidance, and is closest to the LGEM model. The intensity forecast at 72 hours and beyond is quite uncertain since it depends on exactly how much land interaction occurs with Carlos. FORECAST POSITIONS AND MAX WINDS INIT 13/2100Z 15.2N 100.0W 75 KT 85 MPH 12H 14/0600Z 15.6N 100.4W 80 KT 90 MPH 24H 14/1800Z 16.1N 101.1W 90 KT 105 MPH 36H 15/0600Z 16.7N 102.0W 95 KT 110 MPH 48H 15/1800Z 17.3N 103.0W 90 KT 105 MPH 72H 16/1800Z 19.4N 104.9W 65 KT 75 MPH...INLAND 96H 17/1800Z 21.0N 106.0W 45 KT 50 MPH...OVER WATER 120H 18/1800Z 23.0N 106.5W 35 KT 40 MPH $$ Forecaster Blake NNNN