SEATTLE -- The National Weather Service reported Sea-Tac Airport reaching 103 degrees, making it the hottest day in the history of local weather records.

The previous all-time record high was 100 degrees and was set on July 20, 1994, at Sea-Tac Airport and on July 16, 1941, when records were kept downtown at the Federal Building. Weather records for Seattle began in 1891.

According to the National Oceanic and Atmospheric Administration (NOAA), on Wednesday at 9 a.m. Sea-Tac was already at 88 degrees. By noon -- 93 degrees, 2 p.m. 99 degrees and from there it went up one degree every hour, topping out at 103 degrees at 5 p.m. By 6 p.m., it had dropped back down to 102 degrees.

The average high temperature on this date is 76 degrees.

The National Weather Service at Sand Point in Seattle recorded 105 degrees, but the records depend on the temperature at Sea-Tac Airport.

In the south Sound, Olympia tied their record of 104 degrees. Other local temperatures from the National Weather Service include:

Bellingham: 96 degrees, tied their record
Renton: 105
Puyallup: 106
Shelton: 104
Port Angeles: 92
Centralia: 107

Overnight temperatures were also warm: A sign at the Pemco building in Seattle showed it was 70 degrees at 3:40 a.m.

The official low at Sea-Tac was 71 degrees Wednesday morning, making it the warmest low temperature on record. The old all-time record warm low of 69 degrees was set back on Sept. 2, 1974.

The heat wave prompted an excessive heat warning, and is blamed for a brief power outage and medical problems.

As of 6:30 p.m. Wednesday, Tacoma Power reported about 10,000 people are without power. Officials do not know what caused the outage, but crews were working on the problem.

Power was restored to 13,000 who lost electricity for about a hour in Monroe. Snohomish Public Utilities said "line sag" due to the heat was the cause.

Meanwhile, seven people have come to Tacoma General Hospital with heat-related problems, a hospital spokesman said.

WATCH IT: Residents Switching Routines During Heat

The National Weather Service has extended the excessive heat warning from Thursday at 6 p.m. to Friday at 6 p.m. An air stagnation advisory is also in effect until 6 p.m. Friday.

Mayor Nickels said city workers will figure out ways to deliver water to the homeless and that the city's Human Services Department will start calling elderly clients to check on their welfare.

The Meals on Wheels program is offering extra bottles of water with the meals it delivers.

An excessive heat warning means that a prolonged period of dangerously hot temperatures will occur. The combination of hot temperatures and high humidity will combine to create a dangerous situation in which heat illnesses are likely. Drink plenty of fluids, stay in an air-conditioned room and stay out of the sun.

Also be sure to check up on relatives and neighbors.