ZCZC HFOTCDCP5 ALL TTAA00 PHFO DDHHMM HURRICANE MADELINE DISCUSSION NUMBER 17 NWS CENTRAL PACIFIC HURRICANE CENTER HONOLULU HI EP142016 1100 AM HST TUE AUG 30 2016 The satellite presentation of Madeline showed a brief improvement this morning but has since degraded in the presence of increasing vertical wind shear. An Air Force Reconnaissance aircraft has made several helpful passes through the hurricane this morning. Maximum flight level winds of 100 kt were recorded in the northeast quadrant, though a peak SFMR observation of 115 kt was reported. Meanwhile, Dvorak current intensity estimates ranged from 6.0/115 at HFO to 5.0/90 kt out of JTWC and SAB, while all agencies produced a Final T of 5.0/90 kt. Given the minimum pressure reports from the aircraft and the range of the data, the current intensity is lowered to 100 kt. The initial motion for this advisory is 270/09 kt. Madeline is moving westward along the southern edge of a low to mid level ridge, while a shallow upper level trough continues to dig toward the hurricane from the northwest. The ridge will keep Madeline on a westward-moving track today, followed by a gradual turn toward the west-southwest tonight and Wednesday as the ridge to the north builds and the upper level trough imparts northerly winds in the high levels of the cyclone. This track will take the center of Madeline dangerously close to the Big Island of Hawaii late Wednesday and Thursday. Given its close approach and uncertainty in the track forecast, a Hurricane Warning has been issued for the Big Island of Hawaii. Late Thursday and Friday Madeline is forecast to turn back toward the west-northwest as the upper level trough digs southward over Hawaii. The forecast track is essentially an update of the prior advisory and is slightly north of the middle of the guidance envelope. The notable northern outlier continues to be the GFDL. As the upper level trough digs southward, vertical wind shear is expected to induced slow weakening of Madeline through the next five days. UW CIMSS estimates current vertical wind shear from the west-southwest at 13 kt, and SHIPS forecasts shear to gradually increase during the next 24 to 36 hours. The intensity forecast is similar to the prior advisory package, and the rate of weakening is slightly slower than IVCN. It is worth noting that SHIPS weakens the system at a faster rate. Although it will be weakening, Madeline is expected to remain a dangerous hurricane as it passes near the Big Island of Hawaii late Wednesday into early Thursday. Users are reminded to not focus too closely on the exact forecast track, as small changes can lead to differences in impacts and that hazards associated with hurricanes can extend well away from the center. FORECAST POSITIONS AND MAX WINDS INIT 30/2100Z 19.3N 149.4W 100 KT 115 MPH 12H 31/0600Z 19.2N 150.9W 95 KT 110 MPH 24H 31/1800Z 18.9N 152.8W 90 KT 105 MPH 36H 01/0600Z 18.6N 154.9W 80 KT 90 MPH 48H 01/1800Z 18.2N 157.2W 70 KT 80 MPH 72H 02/1800Z 18.3N 161.3W 60 KT 70 MPH 96H 03/1800Z 18.8N 167.1W 55 KT 65 MPH 120H 04/1800Z 19.5N 172.8W 50 KT 60 MPH $$ Forecaster Wroe NNNN