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ZCZC MIATCDEP2 ALL TTAA00 KNHC DDHHMM Hurricane Aletta Discussion Number 8 NWS National Hurricane Center Miami FL EP022018 300 PM MDT Thu Jun 07 2018 An eye has become apparent in visible geostationary satellite imagery, although the central deep convection is not very symmetric on enhanced infrared imagery. Based on a blend of objective and subjective Dvorak T-numbers, the current intensity is estimated to be 65 kt, which makes Aletta the first eastern North Pacific hurricane of 2018. Since the system should continue to traverse a warm ocean and experience weak vertical shear for the next day or two, additional strengthening is forecast. By Saturday some increase in shear is likely, which should cause weakening to commence. The official intensity forecast is at the high end of the numerical guidance. Aletta has been moving somewhat north of the previous track projections, and the initial motion is about 300/5 kt. The main factors controlling the steering of the hurricane are a mid-level ridge to the northeast and a weakness in the ridge to the northwest of Aletta, as well as the future intensity of the cyclone. There is significantly more spread in the track guidance model than is usual for an east Pacific tropical cyclone. The GFS and HWRF, which depict a stronger system, have the northernmost tracks. The ECMWF, which does not show that strong of a cyclone in its forecast, predicts the southernmost track. The official forecast lies between these options and is close to the corrected consensus guidance. This is somewhat north of the previous NHC track. FORECAST POSITIONS AND MAX WINDS INIT 07/2100Z 15.3N 110.0W 65 KT 75 MPH 12H 08/0600Z 15.6N 110.5W 75 KT 85 MPH 24H 08/1800Z 16.1N 111.5W 80 KT 90 MPH 36H 09/0600Z 16.5N 112.3W 80 KT 90 MPH 48H 09/1800Z 17.1N 113.0W 75 KT 85 MPH 72H 10/1800Z 18.7N 114.6W 60 KT 70 MPH 96H 11/1800Z 19.3N 116.7W 45 KT 50 MPH 120H 12/1800Z 19.5N 118.5W 30 KT 35 MPH $$ Forecaster Pasch NNNN