When stocks get too hot, they eventually cool down. That's the basic wisdom behind momentum indicators, and right now three major airline stocks are flashing warning signs for traders who pay attention to these signals.
The Relative Strength Index, or RSI, measures how a stock performs on up days versus down days. Think of it as a fever thermometer for momentum. When the reading climbs above 70, the stock is generally considered overbought, meaning it might be due for a breather after a strong run. Here's where things stand as of December 17, 2025.
Delta Air Lines (DAL)
Delta has been on a tear lately, climbing roughly 28% over the past month to reach a 52-week high of $72.34. UBS analyst Atul Maheswari clearly sees more upside, having initiated coverage on December 12 with a Buy rating and a $90 price target.
But the momentum gauge tells a different story in the near term. Delta's RSI currently sits at 71.9, just past that overbought threshold. The stock itself doesn't seem too concerned, though, dipping only 0.2% to close at $71.14 on Tuesday. Delta also sports strong underlying metrics with a momentum score of 91.92 and a value rating of 93.51.
United Airlines (UAL)
United Airlines is running even hotter. The stock has surged about 25% over the past month, and shares jumped 4.4% on Tuesday alone to close at $112.48, approaching its 52-week high of $116.00.
Like Delta, United received bullish treatment from UBS on December 12, when Maheswari initiated coverage with a Buy rating and set a price target of $142. That suggests significant upside if the analyst is right. But the RSI reading of 72.6 indicates the stock might need to catch its breath first.
Southwest Airlines (LUV)
If Delta and United are running hot, Southwest is positively scorching. The airline's stock has rocketed 32% higher over the past month, with shares gaining another 1.1% on Tuesday to close at $42.17. That puts it near its 52-week high of $43.54.
The bullish sentiment here is palpable. On December 16, Barclays analyst Brandon Oglenski upgraded Southwest from Equal-Weight to Overweight and nearly doubled the price target from $34 to $56. But here's the tension: Southwest's RSI stands at 85.1, well into overbought territory and the highest of the three airlines.
So what does this all mean? The RSI doesn't predict crashes or guarantee pullbacks. It simply suggests that momentum has gotten stretched and that some consolidation or profit-taking wouldn't be surprising. The analysts clearly believe in the fundamental stories here, with price targets well above current levels. But for traders watching technical signals, these three names are worth monitoring closely as the quarter winds down.