Photograph by Dominic Clinton

 Mr. Clinton wrote, "These Mammatus appeared briefly today for 5 minutes at about 6pm (sunset) here in Prachinburi, Eastern Thailand. The day has been fairly sunny with scattered discrete cloud, no haze, light wind, temp about 87-90f. About 45 minutes after the mammatus appeared, a very strong blustery wind started up out of nowhere, rather like the wind that precedes a big thunderstorm (common here now early evening, as the rainy season has just begun). The windiness lasted 15 minutes, and then faded away over the course of another 10 minutes. It was a little odd to have the wind but then no rain - not the usual pattern here.(Our thunderstorms usually have "torn" and ragged wisps of small cloud moving in variable directions below the actual storm cloud - this is almost a guaranteed predictor of heavy precipitation and lightning.)"

WeatherWing:  Mammatus usually do not appear to come out of the blue without the presence of the anvil from which they most likely emanated.  It had to have been there, somewhere at some point even though it may not have been visible to you, since the pouches form from heavy, dropping, icy water molecules and a CB would have reached such cold heights.  Mammatus can either precede or trail a system, so the strong winds you felt may have been related.