Issued at 200 AM PDT Wed Jul 01 2026
697 WTPZ44 KNHC 010836 TCDEP4 Tropical Depression Four-E Discussion Number 1 NWS National Hurricane Center Miami FL EP042026 200 AM PDT Wed Jul 01 2026 The area of low pressure (95E) over the western East Pacific has continued to become better organized over the last 12 hours. Persistent deep convection has developed primarily over the eastern and southern portions of the circulation, with curved banding features becoming well defined. Recent scatterometer data indicate that the system has developed a closed, although somewhat elongated, low-level circulation with maximum winds around 30 kt. Subjective Dvorak current intensity estimates have increased to T1.5 from TAFB. Based on these developments, the system has been designated as Tropical Depression Four-E, with an initial intensity of 30 kt. The depression is moving north-northwestward (345/6 kt), and this general motion is forecast to continue over the next couple of days along the western periphery of a ridge over the central portion of the eastern Pacific basin. Models are in fairly good agreement with this general motion, and the official NHC forecast lies near the simple and corrected-consensus aids. Towards the end of the period, as the system weakens and turns westward into the low-level flow, there is slight timing differences of when that occurs based on the convective structure. The NHC forecast continues to lie near or just to the left of the consensus aids towards the end of the period. The system has about a day or so to strengthen within a favorable low-shear, moist environment, supported by upper-level divergence. The official forecast has the system strengthening into a tropical storm later today, which is good agreement with the latest intensity aids. However, as the system moves north-northwestward, it will encounter cooler SSTs along its track. In about 36–48 hours, wind shear is forecast to increase, and the system will move into a drier mid-level airmass. Given the combination of cooler SSTs and the increasingly unfavorable environment, the system is forecast to weaken and will eventually struggle to sustain deep convection. Simulated IR imagery from the GFS and ECMWF suggests the system could become devoid of deep convection by around 60 hours. Thus, the NHC forecast calls for the system to weaken into a post-tropical remnant low at that time, and dissipating into an open trough by the end of the forecast period. FORECAST POSITIONS AND MAX WINDS INIT 01/0900Z 14.5N 126.9W 30 KT 35 MPH 12H 01/1800Z 15.2N 127.0W 35 KT 40 MPH 24H 02/0600Z 16.3N 127.1W 35 KT 40 MPH 36H 02/1800Z 17.4N 127.3W 35 KT 40 MPH 48H 03/0600Z 18.4N 127.8W 30 KT 35 MPH 60H 03/1800Z 19.2N 128.6W 25 KT 30 MPH...POST-TROP/REMNT LOW 72H 04/0600Z 19.7N 129.6W 25 KT 30 MPH...POST-TROP/REMNT LOW 96H 05/0600Z 20.3N 132.4W 20 KT 25 MPH...POST-TROP/REMNT LOW 120H 06/0600Z...DISSIPATED $$ Forecaster Kelly
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