The biggest Saturday of the college football season so far will feature a rare SEC showdown, a big-time drawing card in Death Valley and lots of rain.
Five games matching ranked teams will provide some separation between the contenders and pretenders in the College Football Playoff race. Another three games between ranked teams and undefeated ones will give an idea if those unranked and unblemished teams have also been underrated.
Some things to watch for a huge Week 5 schedule:
The combination of Hurricane Joaquin headed for the United States and a rain storm already soaking the East Coast could make for some soggy showdowns. Most likely to be affected are two games sharing top billing this weekend, one in Athens, Georgia, and the other in Clemson, South Carolina.
No. 13 Alabama (3-1) visits Sanford Stadium for the first time since 2008 to face No. 8 Georgia (4-0). Both teams can rely on their running games if wind and rain make it tough for the quarterbacks. Bulldogs running back Nick Chubb has 12 straight 100-yard rushing games, one shy of Herschel Walker's school record. The sophomore is sixth in the nation, 149.8 yards per game. The Crimson Tide can give it to Derrick Henry, who is averaging 105 yards per game and has scored eight touchdowns.
No. 6 Notre Dame (4-0) is making its first trip to Clemson since 1977 for the third game ever between the Fighting Irish and 12th-ranked Tigers. Weather forecasts were calling for rain fall that could approach 20 inches in the area for a game that has been such a hot ticket that Clemson coach Dabo Swinney said he couldn't get Jesus a ticket.
Indiana, Iowa and Kansas State have yet to impress poll voters with their perfect starts. One more win this weekend should change that.
The Hoosiers, 4-0 for the first time since 1990, have the toughest task with No. 1 Ohio State (4-0) coming to Bloomington. Indiana's offense features an NFL prospect at quarterback in Nate Sudfeld and the second-leading rusher in the country in Jordan Howard, but the defense ranks near the bottom of the Big Ten. To make things even more difficult for the Hoosiers, they will have to stop Ezekiel Elliott and Cardale Jones without suspended defensive lineman Darius Latham.
Iowa is 4-0 for the first time since 2009, which was also the last year the Hawkeyes beat No. 19 Wisconsin (3-1) in the battle of the Heartland Trophy. Iowa goes to Madison, Wisconsin, trying to break a three-game losing streak to the Badgers.
Kansas State (3-0) is off to its best start since 2012 as it heads to Stillwater, Oklahoma, to face No. 20 Oklahoma State (4-0). The Wildcats have the top defense in the Big 12 by yards per play and will need it to contain Cowboys quarterback Mason Rudolph, who is averaging 309 yards passing per game.
HERE WE GO AGAIN
After taking No. 4 TCU down the wire in a wild 55-52 loss last week, Texas Tech now faces No. 5 Baylor (3-0). Expect another point-a-minute type of game.
The Bears have surpassed 700 yards in each of their nonconference games and are averaging 64 points per game. The Red Raiders (3-1) are averaging 53.8 points per game and 595 yards.
Las Vegas odds makers have set the over/under at 88.
PAC-12 BOUNCE BACKS
Oregon and Arizona State are both 2-2 and out of the rankings after getting blown out at home last week. Both have conference road games to try to get back on track, but the Ducks seem to have the easier trip.
Oregon hopes QB Vernon Adams (finger) is healthy enough to play at Colorado. The Ducks have crushed the Buffaloes the last four times they have met, but Colorado (3-1) is off to its best start since 2009.
Arizona State goes to No. 7 UCLA (4-0), which beat the Sun Devils 62-27 in Tempe last year.
The winner of the Air Force-Navy game has won the Commander-in-Chief's Trophy every year since 1997.
The Falcons (2-1) visit star quarterback Keenan Reynolds and the Midshipmen (3-0) having won three of the last five meetings.
Follow Ralph D. Russo at www.Twitter.com/ralphDrussoAP