# Hurricane Simon Intensifies Off Mexico as Satellite Sensors Reveal Atmospheric Waves Advanced earth observation imagery captures dangerous coastal impacts alongside high-altitude atmospheric gravity waves. - **Source:** [NASA](https://www.nasa.gov) - **Published:** 2026-10-14 - **Topic:** [Business](https://brifing.si/c/business) - **Original article:** - **On Brifing:** https://brifing.si/s/f45c850a-4d59-4604-a57c-65c92fe9d1e5 ## Category 4 Cyclone Approaches Hurricane Simon developed into a major Category 4 tropical cyclone off Mexico's Pacific coast on October 11, 2026. The storm generated maximum sustained winds reaching 250 kilometers per hour as it moved north-northwest, threatening coastal populations with intense precipitation and dangerous surf conditions. ## Suomi NPP Satellite Monitoring The Suomi NPP satellite observed Simon's eye situated approximately 50 kilometers offshore between Manzanillo and Puerto Vallarta. The VIIRS instrument captured high-resolution imagery around 2:30 p.m. local time, showing wind speeds moderating to 210 kilometers per hour as the core interacted with land. ## Topographic Damping by Sierra Madre The National Hurricane Center noted that the rugged terrain of the Sierra Madre mountains diminished the storm's intensity and compressed its wind field. Despite this friction, Simon generated severe flooding in Manzanillo and elevated the risk of catastrophic mudslides across vulnerable mountainous communities. ## Mesospheric Gravity Waves Detected Nighttime data from NOAA-21's VIIRS sensor captured atmospheric gravity waves radiating into the mesosphere. Latent heat released near Simon's eyewall triggered intense updrafts within cumulonimbus clouds, launching energy pulses upward through the stratosphere and mesosphere during the storm's peak convective development phase. ## Sensor Sensitivity and Nighttime Conditions These upper-atmospheric ripples are rarely visible because stratospheric winds often dissipate them before they reach the mesosphere. Minimal moonlight during the NOAA-21 flyover enabled the VIIRS day-night band to detect the faint airglow emitted by high-altitude gases without interference from reflected lunar light. ## Trajectory and Track Uncertainty By the morning of October 13, NHC forecasters assigned very low confidence to Simon's projected track and intensity models. The system's erratic steering defied conventional meteorological expectations, creating significant ambiguity regarding whether it would enter the Gulf of California prior to making landfall. ## Nearshore Swells and Logistics Severe coastal swells produced hazardous maritime conditions along Mexico's southwestern and west-central coastlines. These large waves disrupted port operations and maritime navigation near Manzanillo, demonstrating how offshore cyclones create regional infrastructure hazards even when avoiding a direct, catastrophic eye landfall. ## Strategic Earth Observation Value The multispectral analysis of Hurricane Simon underscores the expanding operational utility of polar-orbiting satellite fleets. Combining day-night visible imagery with upper-atmospheric dynamics provides forecasters with deeper visibility into cyclone thermodynamics, strengthening hazard assessment protocols for coastal defense and critical infrastructure managers. ## Sources covering this story - https://science.nasa.gov/earth/earth-observatory/hurricane-simon-lurks-off-the-mexican-coast/ — --- _Summary written by Brifing from the original reporting. Copyright in the original article belongs to its publisher; read the full piece at the link above._