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| #880400 (Received by flhurricane at: 9:51 PM 23.Nov.2016) TCDAT1 HURRICANE OTTO DISCUSSION NUMBER 13 NWS NATIONAL HURRICANE CENTER MIAMI FL AL162016 1000 PM EST WED NOV 23 2016 A strong convective burst occurred near the center of Otto as an Air Force Reserve Hurricane Hunter aircraft investigated the cyclone near 0000 UTC. This resulted in the aircraft reporting central pressures near 977-979 mb, 850-mb flight-level winds in excess of 100 kt, and dropsondes supporting surface winds of at least 80 kt. However, these winds may have been associated with a transient mesocyclone in the strong convection, as data from a subsequent penetration showed a central pressure near 981 mb and lower winds. The initial intensity is now 75 kt based on 700-mb flight-level winds from the last aircraft pass, and there is a larger than normal uncertainty about this value. Conditions appear favorable for additional strengthening before the hurricane makes landfall over Central America on Thursday, and the intensity forecast shows modest strengthening for the first 12 hours. Otto should weaken significantly while crossing southern Nicaragua and northern Costa Rica, and it is expected to emerge into the Pacific as a tropical storm between 24 and 36 hours. Strong easterly vertical shear should prevent re-intensification, and the new intensity forecast follows the trend of the previous forecast in showing a slow decay to a remnant low by 120 hours. However, it should be noted that the Pacific portion of the intensity forecast lies near the low end of the intensity guidance. Otto is moving a little faster with the initial motion now 275/8. The hurricane should make landfall over southern Nicaragua or northern Costa Rica sometime on Thursday. After landfall, a strong low- to mid-level ridge to the north should steer the cyclone westward to west-southwestward through 96 hours. Near the end of the forecast period, Otto or its remnants should approach the western end of the ridge and turn west-northwestward. The track guidance remains in good agreement, and the new forecast track is a slightly faster version of the previous track. FORECAST POSITIONS AND MAX WINDS INIT 24/0300Z 11.2N 82.2W 75 KT 85 MPH 12H 24/1200Z 11.2N 83.3W 80 KT 90 MPH 24H 25/0000Z 10.9N 85.2W 60 KT 70 MPH...INLAND 36H 25/1200Z 10.5N 87.4W 45 KT 50 MPH...OVER WATER 48H 26/0000Z 10.0N 89.5W 40 KT 45 MPH 72H 27/0000Z 9.5N 94.5W 40 KT 45 MPH 96H 28/0000Z 9.5N 99.0W 35 KT 40 MPH 120H 29/0000Z 11.0N 103.0W 25 KT 30 MPH...POST-TROP/REMNT LOW $$ Forecaster Beven |
