Mann: Expect average flooding, warm and dry summer

At this time of year, the Inland Northwest usually sees its greatest risk of high waters. Melting snowpacks and occasional torrential rainfall increase the threat of flooding, often in the foothills of the Cascade Mountains and the highlands of northeastern Washington, as well as across portions of North Idaho and Western Montana.

This year, according to the National Weather Service in Spokane, “the total volume of water that will flow in the Inland Northwest rivers and streams in 2012 is forecast to be near normal or just above normal for most basins.” The potential for flooding from spring snowmelt is low for most areas, but there are some rivers in Idaho that have a moderate chance for flooding for the rest of the season. However, a series of moderate to heavy thunderstorms could change that.

There have been a number of years when the Inland Northwest has seen high waters. In February 1996, there was widespread flooding in Washington, Oregon and Idaho. The rivers of western and southeast Washington went far above flood stage. Major flooding occurred in North Idaho and Washington, with overall damage estimated at $800 million.

Perhaps the worst flood seen in recent times across our region happened in May and June 1948. This event is listed as the second biggest weather event in Washington’s history. During that time, there was widespread flooding across the region, especially along the Columbia River. All-time record river levels were reported.

In terms of our local weather, it appears that we’re now in our sun-and-showers weather pattern. Conditions are looking drier and warmer over the next few weeks. But, don’t be surprised to see occasional showers and a few thunderstorms.

The summer still looks much warmer and drier than usual. Most of the shower and thunderstorm activity should stay over the mountain areas. This summer looks like one of the warmest ones since 2006.