To the list of obstacles standing between the Patriots and 16-0, add one more — the weather.

The games are all outdoors from here on in — the next three in New England against the Steelers, Jets and Dolphins and the season finale in the wind-swept swamps of New Jersey against the Giants. And for a team that has a good, but not a great rushing attack, one really bad day of weather could end up messing up perhaps the greatest season the game has ever seen.

It would be more than ironic if that were to happen, because New England has always been the kind of team that could lock you down in bad weather and then do just enough on offense to win the game. But as the Eagles last week and the Ravens on Monday night have shown, New England is not the defensive outfit it used to be, especially against the run.

They gave up 166 yards on the ground to the Ravens, and if Baltimore hadn’t done everything possible to throw away a game they had all but wrapped up, that would have been the story. And from now until February, we would've been writing about the Pats’ suspect run defense and whether it would cost them their fourth Super Bowl win.

On the other hand, the Patriots don’t grind out yards on the ground. In Monday night’s Escape from Baltimore, they had 90 rushing yards, which is decent against the Ravens’ defense, but not the stuff of which cold-weather victories are made.

Brady did the things he had to do to win in the fourth quarter, but he had just 18 completions in 38 attempts in the gusting winds of Baltimore. Probably no more than a half dozen of the misses were due to the wind, but Brady’s receivers dropped another half dozen, and how many of those were due to the cold and fluttering football is a matter of conjecture.

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As the weather gets worse, his numbers aren’t going to get appreciably better. And with just four games to go, New England has all but locked up home-field advantage for the AFC postseason.

Home field is good, or so the common wisdom goes. But the Pats are a passing team, a team that’s going to be darned near impossible to beat if it gets to the Super Bowl and a perfect field in perfect weather. But between now and then, neither fields nor weather are likely to be perfect.

Philly and Baltimore also built their defensive game plans around making Randy Moss disappear and playing as many as eight men in coverage, leaving Brady with fewer options in the passing game. And the results showed in Brady’s reduced numbers. The Pats won both games, but it’s not been easy.

Now the Steelers, who are well adapted to playing in lousy conditions, are coming to town, armed with two weeks of game films showing how two teams almost knocked off the Pats and led by defensive whiz Dick Lebeau. He’ll add his own wrinkles to what the Eagles and Steelers did, and if the Pats thought it’s been tough the past two weeks, it’s about to get even tougher.

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The Patriots are still the NFL's best team and could prove to be the best ever. Bu there are four games to go in the regular season and three more in the playoffs before the coronation can begin.

And this thing that the Patriots are trying to do gets harder by the week. New England is preparing for each game as it always does — to win the game, solidify their playoff position, to keep getting better for the postseason. Their opponents are preparing for the biggest game they’ve ever played, cranking themselves up for the supreme effort it will take to keep the Patriots from perfection.

They’d almost have been better off if they’d lost a game by now. There would be no pressure to run the table, no string of opponents trying to knock them off their perch, none of the pressure they’re facing now.

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It’s a lot easier with one loss. No team like the Jets or Miami has a reason then to play out of their heads to beat the Patriots — or beat them up. But now even those games could be desperate struggles.

Earlier in the season — even a few weeks ago — it was a lot easier for the Pats to dispose of such opponents: Just let Brady rifle passes all over the field and grind foes into the turf. But the passes aren’t as easy to complete now that the air is raw and the winds are gusting. The likelihood of interceptions goes up and the margin for error gets slimmer than Kate Moss.

Those game-winning passes on fourth down aren’t nearly as easy to pull off in January in Foxboro as they are in September. And whether home field is an advantage for the Patriots remains to be seen.

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