ZCZC MIATCDEP3 ALL TTAA00 KNHC DDHHMM HURRICANE MARIE DISCUSSION NUMBER 18 NWS NATIONAL HURRICANE CENTER MIAMI FL EP132014 200 AM PDT TUE AUG 26 2014 Microwave images indicate that Marie still has a double eyewall structure, though the outer eyewall is open on the north side. The eye of the hurricane remains fairly distinct in satellite images, but deep convection is not as intense as it was earlier. The initial intensity is lowered to 90 kt, following the Dvorak CI-numbers from TAFB and SAB. An ASCAT pass around 0500 UTC indicated that despite the weakening, the wind field of Marie remains very large. The hurricane is moving across a sharp sea surface temperature gradient, and it is expected to cross the 26 degree C isotherm later today. These cold waters, combined with a drier and more stable air mass, should cause Marie to continue weakening at a steady pace. The NHC intensity forecast is an update of the previous one and shows Marie becoming a post-tropical cyclone by 72 hours when it is expected to be over water temperatures below 23 C. Marie is moving northwestward at 12 kt. A west-northwestward to northwestward motion at about the same forward speed is forecast during the next few days while the system remains steered by mid-level ridging to its northeast. A slow down and turn toward the north-northwest is expected by the end of the forecast period when the weak system is steered by the lighter low-level flow. The NHC track forecast is nudged to the south this cycle, toward the latest consensus aids. Very large southerly swells continue to affect much of the Baja California peninsula, and will soon reach the southern California coast. These swells are expected to persist for a couple of days, and could produce life-threatening surf and rip currents, as well as minor coastal flooding. FORECAST POSITIONS AND MAX WINDS INIT 26/0900Z 19.9N 117.8W 90 KT 105 MPH 12H 26/1800Z 20.9N 119.5W 75 KT 85 MPH 24H 27/0600Z 21.9N 121.8W 60 KT 70 MPH 36H 27/1800Z 22.9N 124.4W 50 KT 60 MPH 48H 28/0600Z 24.2N 126.8W 40 KT 45 MPH 72H 29/0600Z 27.3N 130.8W 35 KT 40 MPH...POST-TROPICAL 96H 30/0600Z 29.9N 132.6W 30 KT 35 MPH...POST-TROP/REMNT LOW 120H 31/0600Z 30.5N 133.2W 25 KT 30 MPH...POST-TROP/REMNT LOW $$ Forecaster Cangialosi NNNN