Change can be good in the NHL.

That's what the trade deadline is all about, in fact, and there are quite a few teams who could benefit from an in-season upgrade as the road to the 2017-18 NHL playoffs narrows.

Change, however, isn't always good, and some of the league's top contenders should be preaching that this week.

The Washington Capitals, Nashville Predators and Tampa Bay Lightning are all riding win streaks of at least three games, and they've been on the rise since before even these latest runs. The Lightning are on a different level altogether with their all-world goal differential and seven straight W's to their name, but it's hard to find anyone outside of maybe the St. Louis Blues and Los Angeles Kings who rival them, the Caps and the Preds as the NHL's best as of December.

Farther down in the standings, the Philadelphia Flyers aren't to be overlooked, especially since they were all but ruled dead after a 2-5-6 November that had Dave Hakstol on the hot seat. But others, like the Toronto Maple Leafs and the Calgary Flames, aren't quite as heralded in our latest edition of NHL Power Rankings thanks to some recent slip-ups.

Biggest Movers
5 Blackhawks
4 Flames
1 Lightning There's no reason to call their tear unsustainable until it looks, you know, unsustainable. -- 46-30-6
2 Predators Pekka Rinne seriously must've found a time machine after the Stanley Cup Final. 2 42-32-8
3 Blues It's not often you'll see Jake Allen save 42 shots and the Blues still lose. They're good and getting healthier. -- 37-38-7
4 Kings Anze Kopitar is right: The Kings need to start acting like they're winners. 2 47-25-10
5 Capitals Like L.A., they've been a pleasant surprise. Ovi is cooking. 4 35-37-10
6 Golden Knights How much better does it get than Marc-Andre Fleury outdoing the Penguins? 2 51-22-9
7 Jets Giving St. Louis a taste of its own medicine: Another sign these Jets are no fluke. 1 46-33-3
8 Maple Leafs They could probably stand to drop even farther. Out-shot and off the mark, they should be fine down the road. 3 50-21-11
9 Blue Jackets Talk out of Columbus says this team's X-factor is rebounds. 2 25-48-9
10 Devils They're doing OK withstanding a banged-up stretch. 1 52-22-8
11 Blackhawks The Kane-Saad-Toews trio is finally surging. And topping the Wild was huge. 5 26-49-7
12 Rangers 'Streaky' is their name this season. It's good to see some juice after a bit of deflation. -- 47-22-13
13 Islanders Their third line is one to watch in the coming weeks. 3 42-31-9
14 Sharks All eyes are on Logan Couture. 1 22-44-16
15 Stars The inconsistencies are more apparent here than maybe anywhere else as of December. 3 47-21-14
16 Wild There will be a Midwestern sigh of relief when Zach Parise is back. 3 46-25-11
17 Penguins Needing all three periods against Arizona to get back on track is peak 2017 Pens. 3 40-31-11
18 Flyers They would be higher here if they didn't trample over mostly so-so teams. Dave Hakstol has to be thrilled, though. 3 31-38-13
19 Flames Things finally broke their way Sunday, and it was about time. Their 2-0 loss to Nashville actually had plenty of promise. 4 38-27-17
20 Bruins Imagine if Erik Karlsson ended up here. 3 65-12-5
21 Ducks What a week for John Gibson. 3 23-47-12
22 Hurricanes So maybe there is life here. Hat tip to Scott Darling. 3 52-21-9
23 Canucks At what point do the Canucks regret their offseason emphasis on short-term vet additions? 3 38-37-7
24 Avalanche Matt Duchene is long gone, but they have some building blocks. 2 51-24-7
25 Oilers They really need Monday's showdown with the Sharks. 1 50-23-9
26 Canadiens The cold weather isn't an excuse for falling 3-0 to the Senators. 3 31-45-6
27 Red Wings How much longer will we see the Henrik Zetterberg era? 1 35-37-10
28 Senators Now we have Don Cherry saying they'll peace out of Ottawa if the fans don't show up. That describes 2017. 1 39-35-8
29 Panthers They're still fighting. Will the fans fight with them? 2 42-32-8
30 Sabres The clock is on for Jack Eichel's ascension to captaincy. -- 42-33-7
31 Coyotes They might not reach double-digit victories until well after the new year. -- 28-40-14