Issued at 200 AM MST Wed Oct 14 2026
000 WTPZ45 KNHC 140846 TCDEP5 Hurricane Simon Discussion Number 28 NWS National Hurricane Center Miami FL EP202026 200 AM MST Wed Oct 14 2026 Proxy-visible and infrared satellite images of Simon show the tiny eye of the hurricane has filled during the past few hours. There has also been a warming of the inner core cloud tops, and the central dense overcast has become less symmetric. These changes could be the result of some northerly shear affecting Simon as diagnosed by UW-CIMSS. There is no recent passive microwave data available to assess the internal structure of Simon, but recent scatterometer data and distant radar data from Los Cabos indicate that the hurricane remains very small. The initial intensity is lowered slightly to 90 kt, in best agreement with the latest Dvorak CI number (5.0) from TAFB and an earlier 88-kt D-MINT estimate. The hurricane is moving slowly southwestward (230/3 kt). In the near term, Simon is expected to remain within very weak steering currents. Thus, it is likely to meander well offshore of west-central Mexico during the next couple of days, with the model consensus generally favoring a slow southwestward or southward motion through Thursday. From there, the future track will depend on the vertical depth of Simon and its interaction with an upper-level trough over the western United States. This feature should cause Simon to turn northward at some point, but there is large spread among the track models as to when and where this turn occurs. There has been a substantial westward shift in the long-range track guidance, with almost all models now bringing Simon near or west of the Baja California Peninsula at 72-120 h. The NHC forecast has been adjusted in the direction of the latest multi-model consensus to reflect this trend, but future adjustments will likely be required. Simon's small size makes it susceptible to intensity fluctuations based on the state of its compact inner core and small changes in the environmental conditions. The hurricane is forecast to drift over very warm waters in a fairly weak shear environment during the next day or two. However, the mid-level environmental humidity is only around 50 percent, and even slightly stronger shear than forecast could disrupt the core and induce some weakening. The official NHC forecast shows little net change in the next 24-36 h, recognizing that some of the hurricane regional models show another round of strengthening could occur during this period. There is higher confidence that the aforementioned trough will impart stronger vertical wind shear over Simon by Friday, which should induce a steady weakening trend through the weekend. Simon continues to be a challenging storm to forecast, and confidence remains lower than normal given the weak steering, proximity to land, very small size, and significant model spread. Key Messages: 1. Simon could be near Las Islas Marias on Thursday, where a Hurricane Watch remains in effect. Interests in west-central Mexico and Baja California Sur should continue to closely monitor the latest updates. Additional watches or warnings could be required over the next day or two. 2. Large swells will likely affect portions of the coast of west-central Mexico and Baja California Sur over the next several days. These swells could cause life-threatening surf and rip current conditions. FORECAST POSITIONS AND MAX WINDS INIT 14/0900Z 19.8N 107.9W 90 KT 105 MPH 12H 14/1800Z 19.6N 108.0W 95 KT 110 MPH 24H 15/0600Z 19.4N 108.1W 90 KT 105 MPH 36H 15/1800Z 19.2N 108.3W 90 KT 105 MPH 48H 16/0600Z 19.6N 108.5W 80 KT 90 MPH 60H 16/1800Z 20.9N 109.1W 65 KT 75 MPH 72H 17/0600Z 22.4N 109.8W 50 KT 60 MPH 96H 18/0600Z 24.6N 111.1W 35 KT 40 MPH...POST-TROP/INLAND 120H 19/0600Z 27.1N 113.0W 25 KT 30 MPH...POST-TROP/INLAND $$ Forecaster Reinhart
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