000 WTPZ45 KNHC 230531 TCDEP5 HURRICANE PATRICIA SPECIAL DISCUSSION NUMBER 13 NWS NATIONAL HURRICANE CENTER MIAMI FL EP202015 1230 AM CDT FRI OCT 23 2015 The purpose of this special advisory is to update for a significant increase in the intensity of the hurricane. Reports from the Air Force Hurricane Hunters indicate that Patricia has intensified at an incredible rate since yesterday. The plane measured peak 700-mb flight level winds of 179 kt in the northeastern eyewall, and this may be an unprecedented value for a tropical cyclone. Using the 90 percent adjustment value to convert this to a surface wind speed yields an intensity estimate of 160 kt, which is tied with eastern north Pacific Hurricane Linda of 1997 for the strongest on record. A dropsonde released into the eye measured a sea-level pressure of 894 mb with 25 kt of wind. Adjusting this pressure for the surface winds (i.e. the drop did not land into the actual center of the eye) gives an estimated minimum central pressure of 892 mb, which breaks the record for the lowest pressure of an east Pacific hurricane. Some fluctuations in intensity are likely today due to eyewall replacements, but Patricia should maintain category 5 status through landfall this afternoon or evening. No changes are made to the track forecast from the previous advisory. This special advisory replaces the 0600 UTC intermediate advisory for Patricia. KEY MESSAGES: 1. Confidence is high that Patricia will make landfall in the hurricane warning area along the coast of Mexico as an extremely dangerous major hurricane this afternoon or evening. Preparations to protect life and property in the hurricane warning area should be completed as tropical storm conditions are beginning to affect the area. 2. In addition to the coastal impacts, very heavy rainfall is likely to cause life-threatening flash floods and mud slides in the Mexican states of Jalisco, Colima, Michoacan and Guerrero continuing into Saturday. FORECAST POSITIONS AND MAX WINDS INIT 23/0530Z 16.5N 105.3W 160 KT 185 MPH 12H 23/1200Z 17.4N 105.7W 160 KT 185 MPH 24H 24/0000Z 19.7N 105.3W 160 KT 185 MPH...INLAND 36H 24/1200Z 22.5N 103.5W 60 KT 70 MPH...INLAND 48H 25/0000Z...DISSIPATED $$ Forecaster Pasch