|Tropical Storm Erick||Winds: 40 kt|
|Pressure: 1004 mbar|
|Advisory 1 / 8:00 AM PDT Sunday, July 28, 2019|
The latest trends in infrared and microwave data this morning suggest that Erick's center of circulation is becoming more well-located within the storm's convection, which has regained some organization since losing some during the last advisory. A 0953z AMSR2 microwave image showed a well-define center of circulation with convection trailing towards the south. An 1116z GMI microwave pass revealed that the center had drifted south of 12N, becoming better nestled in the central thunderstorms. Spiral banding is evident in all quadrants and it appears that a central dense overcast is beginning to take shape. At 12z, UW-CIMSS ADT assessed T3.4/53kt while SAB and TAFB were T2.5/35kt across the board. Based on a blend of these values, improvements in the internal structure of Erick, and the lackluster winds observed on the ASCAT-C data noted in the last advisory, the initial intensity is raised slightly to 40 kt.
Erick's slight south-of-west dip this morning was well-forecast by some of the finer-scale dynamical guidance, but the wobble is only marginal and does not change the overall steering picture, which remains largely the same. A west-northwest track is expected over the next three days with extended ridging towards the storm's north and northeast. Afterwards, the combination of increasing ridging and the storm's lessened intensity towards the end of the forecast should result in a curve back to the west on day 4-5. Models are in tight agreement over this depiction.
Conditions are favorable for intensification within the next two days as Erick remains in the low-latitudes, giving it prolonged access to warmer waters which should remain around 28C for the next day and fall slightly to marginal but still supportive temperatures of 26-27C afterwards. A hostile upper-air environment presents itself after day 3 courtesy of the tropical upper-tropospheric trough near Hawaii, which should greatly increase westerly shear and accentuate the drying deep-layer environment. There remains a significant spread in the intensity guidance, depicting anything from a tropical storm to a major hurricane as the ceiling for Erick. The GFS and ECMWF-IFS each have hurricanes, as do the HWRF and HMON. However, SHIPS/LGEM have once again dropped back from their prior depictions and are back to showing tropical storms. A number of explanations have been forwarded as possible inhibitors in previous advisories, including a suppressed Kelvin wave, association with the monsoon trough, and the storm's forward speed. At least this afternoon, the elongated circulation observed by ASCAT will curb intensification, but once the storm works its way away from the trough intensification could take off, provided this happens before upper-level conditions worsen. Rapid intensification potential remains maximized in around 36-48 hours, while significant weakening is expected after day 3. Indications currently suggest peak intensity in around 60 hours.
FORECAST MAX WINDS
INIT 28/1500Z 40 KT 45 MPH
12H 29/0000Z 45 KT 50 MPH
24H 29/1200Z 60 KT 70 MPH
36H 30/0000Z 70 KT 80 MPH
48H 30/1200Z 80 KT 90 MPH
72H 31/1200Z 90 KT 105 MPH
96H 01/1200Z 50 KT 60 MPH120H 02/1200Z 35 KT 40 MPH