Huffman: Late in the summer, moisture starts coming up
the west coast of Mexico and entering the southwestern U.S. And you transition
from a relatively dry early season to something that's more prone to
thunderstorms and the attendant flash floods. Relatively small amounts
of rain in a desert condition can lead to a flash flood, even
if it's a long way away. The ground is not very good at absorbing water and so
instead it very quickly runs off and can run down channels for miles, perhaps catching
people unaware.
Huffman: In a general sort of way,
we know that it rains in the summer and doesn't rain the rest of the year. But, the
question is: Is it strong or is it weak? These kinds of long-range forecasts
are still quite challenging. Even at the shorter scale, the monsoon
consists of what are called breaks and then surges. And being able to forecast
those breaks and surges a few days or weeks in advance would be a really
great thing. There's a certain capability to do that now, but if we
understand the precipitation processes better that will give us a better handle on
how the heat is released in the dynamical systems that are
contributing to the breaks and surges.