SEATTLE – Puget Sound residents were bracing for more thunder and lighting storms Sunday night, after an early morning storm lit up the skies and caused scattered power outages in parts of Seattle and South King County.

More thunderstorms were expected along the coast and Olympic Peninsula early Sunday evening, and over the Seattle metro area later in the night.

Deanna Kirkpatrick

Lightning strikes in Federal Way, Wash. on Sunday, August 17, 2008.

The National Weather Service warned that the thunderstorms could produce dime-sized hail or larger, with brief, gusty winds.

"There's a better chance (of lightning) in the Seattle area overnight, and into the morning while people are sleeping," said KING 5 meteorologist Chris Warren.

The NWS said the thunderstorms could continue through the day Monday.

On Tuesday, a strong and wet storm more typical of autumn will move in, bringing significant rainfall for this time of year.

Early Sunday morning, reports of lightning came in from as far south as Fort Lewis all the way to Seattle. Seattle City Light reported about 4,000 customers lost power in the Lake City and Briercrest neighborhoods in north Seattle.

Puget Sound Energy said about 1,600 customers lost power in the Factoria area. There were also reports of scattered outages in Auburn, Kent and Federal Way, but no reports of damage.

Lightning may have been behind the dozen fires that were burning Sunday in Olympic National Park. According to visitors, several fires started in the Deer Park area, two near Maiden Peak and another near Grand Valley. The rain was keeping them at bay.

The lightning capped off a three-day heat wave that saw temperatures climb into the 90s in Western Washington. Temperatures on Saturday reached 94 in Shelton, 91 in Puyallup and 98 in Vancouver, Wash. Eastern Washington hit the triple digits, with Ellensburg at 105 and Walla Walla at 104.

On Sunday, temperatures in Puget Sound dropped into the 80s, and the cool-down was expected to continue as the week goes on.

"We're going to go from one extreme to the next," said NWCN meteorologist Nick Allard.

Centralia, Wash. resident Dave Chappell submitted this photo of a lightning strike early Sunday morning.

Allard said Monday brings a chance of showers, as an area of low pressure approaches the coast. Look for temperatures to drop into the 60s by Wednesday.

"Normal temperatures for this time of year are in the mid-70s, so we'll be cooler than normal by Tuesday," Warren said.

In the meantime, thunderstorms have firefighters on alert. A red flag warning for fire danger is in effect for much of Western Washington.

"The high fire danger is due to the fact it's dry, and there are thunderstorms," Warren said.