000 WTPZ42 KNHC 041444 TCDEP2 HURRICANE BLANCA DISCUSSION NUMBER 16 NWS NATIONAL HURRICANE CENTER MIAMI FL EP022015 1000 AM CDT THU JUN 04 2015 It appears that the combination of upwelling and an eyewall replacement cycle has resulted in significant weakening of Blanca during the past 18 hours or so. The eye is not as clear as it was yesterday, and the deep convection is no longer symmetric around what is left of the eye. Based on decreasing subjective and objective T-numbers, the initial intensity has been adjusted down to 95 kt at this time. However, as soon as Blanca moves out of the area where the upwelling has occurred in 12 to 24 hours, another round of strengthening is anticipated, but not as much as indicated yesterday. The NHC forecast is consistent with the SHIPS intensity guidance, which still insists on forecasting restrengthening as the cyclone moves again over warm waters. Beyond 48 hours, increasing shear and cool waters should induce gradual weakening as Blanca approaches the Baja California peninsula. Satellite fixes indicate that Blanca has begun to move slowly toward the northwest or 325 degrees at 3 knots. The subtropical ridge which has been blocking the motion of the cyclone is forecast to shift eastward by most of the global models while a trough approaches the west coast of the United States. This steering pattern favors a general northwest to north-northwest track during the next 5 days. The NHC forecast is similar to the previous one and follows closely the consensus of the ECMWF and the GFS global models. FORECAST POSITIONS AND MAX WINDS INIT 04/1500Z 12.3N 105.1W 95 KT 110 MPH 12H 05/0000Z 13.2N 105.7W 95 KT 110 MPH 24H 05/1200Z 14.5N 107.0W 105 KT 120 MPH 36H 06/0000Z 16.0N 108.5W 105 KT 120 MPH 48H 06/1200Z 17.5N 109.5W 105 KT 120 MPH 72H 07/1200Z 20.0N 110.5W 90 KT 105 MPH 96H 08/1200Z 23.2N 111.5W 50 KT 60 MPH 120H 09/1200Z 26.0N 113.3W 25 KT 30 MPH $$ Forecaster Avila