|Hurricane Erick||Winds: 105 kt|
|Pressure: 962 mbar|
|Advisory 13 / 8:00 AM PDT Tuesday, July 30, 2019|
The rapid intensification of Hurricane Erick is well underway. A pinhole eye, no greater than 10 miles across, has persisted on infrared satellite imagery with the central dense overcast becoming increasingly symmetric all the while, and is also enlarging in the latest satellite frames. As an indication of this intensification, in-house Dvorak assessments at points yielded instantaneous data-T values of T6.5/127kt, constrained to T5.5/102kt current intensities. After latching onto the eye, UW CIMSS-ADT values began registering instantaneous values around T5.3/97kt. SAB, PHFO, and PGTW estimates are range between T5.0/90kt and T6.5/115kt, and this remarkable spread is no surprise given the rapid intensification and resultant constraints. Based on a blend of all available estimates, the initial intensity has been raised to 105 kt, making Erick a major hurricane.
It's not too surprising that Erick is rapidly intensifying as this window of favorable conditions and considerable RI parameters was well-depicted on dynamical guidance for several days. Given the inertia of intensification, we should probably expect to see additional strengthening today. The storm is likely being aided by divergent flow from a shortwave upper-trough that looms about 250 miles downrange. However, as Erick continues tracking west-northwest, wind shear is expected to increase, both from this shortwave feature and the broader tropical upper-tropospheric trough. This will occur in tandem with mid-level relative humidity settling in marginal values, and this worsening of atmospheric conditions is currently in progress. Both the HMON and HWRF have keyed onto tomorrow night being a final period of accelerated strengthening with pressures suggestive of a threshold Category 4 hurricane. Other models also generally show a peak around this time, probably a manifestation of divergent flow aloft from the nearby trough, which has increased over the storm overnight per the UW-CIMSS ADT analysis. The forecast depicts further strengthening, reaching a peak tonight into tomorrow morning before the onset of rapid weakening as HFIP shear indices balloon north of 30 kt on day 2, continuing for the remainder of the forecast.
No changes to the forecast track this advisory as models remain tightly clustered. Ridging should keep Erick on a west-northwest path over the next two days, and a weakened and shallower system will be deflected slightly more westward in days 3-5 as it follows the low-level trades. This path is expected to result in a track approximately 150 nautical miles south of Hawaii.
FORECAST MAX WINDS
INIT 30/1500Z 105 KT 120 MPH
12H 31/0000Z 120 KT 140 MPH
24H 31/1200Z 115 KT 130 MPH
36H 01/0000Z 85 KT 100 MPH
48H 01/1200Z 65 KT 75 MPH
72H 02/1200Z 45 KT 85 MPH
96H 03/1200Z 35 KT 40 MPH120H 04/1200Z 25 KT 30 MPH...POST-TROP/REMNT LOW