Puerto Vallarta is ending October with summer still clinging to the air. Forecasts show highs near 31–32°C and sultry nights, while a broad anticyclone keeps skies mostly clear and the heat in place. Mexico’s weather service expects fewer cold fronts than average this season and warmer minimums across much of the country. Global signals point the same way. Greenhouse gases are at record levels, and sea surfaces remain abnormally warm. Together, t…