We've been very lucky travelers on our many wonderful trips. Even when the 10-day forecast shows rain and lots of it, somehow while we're there it just doesn't rain. Really. We've been so lucky that way. When we were in Vietnam in 2005, it did rain the morning we were going to Hue, but otherwise the weather missed us. There was a typhoon back then that hit northern Vietnam and delayed our flight from Nha Trang to HCMC, but we didn't get the rain.
This time, though, our good weather luck may shift a little bit. That red dot/flag is Hanoi, and the big giant messy-looking weather? That's Typhoon Nesat and Tropical Depression Haitang bearing down on northern Vietnam. The tropical depression will go just south of Hanoi, from the projections I found, but the typhoon is heading pretty directly for Hanoi. Current projections have it around Hanoi Friday afternoon, and we arrive Saturday morning at 9:40 (which means 9:40pm Friday evening in NYC). So we may get some rain, we may get some wind, but we really don't care.
Still. Yikes. And đáng sợ!