000 WTPZ41 KNHC 251458 TCDEP1 HURRICANE AMANDA DISCUSSION NUMBER 12 NWS NATIONAL HURRICANE CENTER MIAMI FL EP012014 800 AM PDT SUN MAY 25 2014 Amanda has continued to rapidly strengthen this morning, although the hurricane is likely near its peak intensity. The 15 n mi diameter eye remains quite distinct in infrared and first-light visible satellite imagery, and a solid ring of cloud tops as cold as -75C surround the eye. Subjective classifications at 1200 UTC from TAFB and SAB were T7.0/140 kt and T6.5/127 kt, respectively. The ADT estimate from UW-CIMSS was T6.6/130 kt, and those values have continued to steadily increase to T6.8/135 kt as of 1330 UTC. A blend of these intensity estimates easily support increasing the intensity to 135 kt, which is just below category 5 strength on the Saffir-Simpson Hurricane Wind Scale. Amanda appears to have stalled during the past few hours and is now drifting slowly northward or north-northwestward at around 2 kt, a motion that has been well forecast in previous advisories over the past 2 days. Amanda is expected to maintain a general northward motion over the next 72 hours as the hurricane moves into a combined southerly steering between a mid-/upper-level trough to its west and a mid-level ridge to its east. By days 4 and 5, Amanda is expected to be a significantly weakened and more shallow cyclone that is forecast to slow down and turn westward under the influence of a large low-level subtropical ridge located from Baja California westward into the central Pacific Ocean. The NHC track forecast is similar to the previous advisory and lies near a blend of the FSSE and TVCE models. Amanda has likely reached its peak intensity, or is very close to it. Although the SHIPS intensity model indicates SSTs warmer than 29C exists beneath and ahead of the hurricane, various SST analysis products at 1200 UTC this morning indicate that cold upwelling has already begun beneath the cyclone, and this cold upwelling should be exacerbated even further now the cyclone is moving at a forward speed of only 2 kt. As a result, steady weakening is expected within the next 12 hours or so. By 36 hours and beyond, southerly to southwesterly winds shear is forecast to increase to more than 20 kt, which should further enhance the weakening process. By day 5, the global models are in good agreement on the low- and upper-level circulations decoupling, which could result in Amanda becoming a remnant low at that time. The official intensity forecast is similar to the previous advisory, and closely follows the intensity model consensus IVCN, which is well below the SHIPS and LGEM models through 36 hours. Amanda is now the strongest May hurricane on record in the eastern Pacific basin during the satellite era. If Amanda were to reach an intensity of 140 kt, it would become the earliest category 5 hurricane on record, beating out Hurricane Ava of 1973. FORECAST POSITIONS AND MAX WINDS INIT 25/1500Z 11.8N 111.1W 135 KT 155 MPH 12H 26/0000Z 12.2N 111.3W 130 KT 150 MPH 24H 26/1200Z 13.0N 111.4W 120 KT 140 MPH 36H 27/0000Z 14.0N 111.6W 105 KT 120 MPH 48H 27/1200Z 15.0N 111.7W 90 KT 105 MPH 72H 28/1200Z 16.5N 111.5W 65 KT 75 MPH 96H 29/1200Z 17.6N 110.7W 45 KT 50 MPH 120H 30/1200Z 18.6N 110.0W 30 KT 35 MPH $$ Forecaster Stewart