Exit-Only Lane, Heavy Traffic, and a Missed UNM Exit
You are southbound on I-25 in Albuquerque at 65 mph at 8:05 a.m. Traffic is heavy but moving. You want the exit for UNM. An overhead guide sign reads EXIT 225 UNM 1/2 MILE, with an arrow pointing to the right lane. At 1/4 mile, a second sign over the right lane includes an EXIT ONLY panel. The right lane is an auxiliary exit lane that begins there; the two left lanes continue through. A mile marker 224.5 is visible on the right shoulder. You are currently in the center lane with a semi-truck close behind and a car in the right lane beside your rear bumper. You have about 20 seconds to the exit gore.
1. What does the EXIT ONLY panel mean for the right lane, and why does the arrow on the first sign matter?
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EXIT ONLY means the right lane must leave the freeway at the upcoming exit; it does not continue through. The arrow on the first sign points to that right lane, telling you which lane serves EXIT 225 for UNM. If you stay in the center lane, you will pass the exit. The panel is also a warning that drivers in that lane cannot simply continue straight, so you should not enter it unless you intend to exit. The sequence of signs is giving you a lane-choice instruction, not just a destination name.
2. Given the truck behind and the car beside, how do you safely enter the exit lane? What if you cross the gore?
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Signal early and adjust speed to create a gap rather than forcing your way in. If the car beside your rear bumper is blocking the lane change, easing off the accelerator may let it pass so you can move in behind it; accelerating aggressively with a truck close behind is riskier. Complete the lane change before the solid white line and the gore area. Crossing the gore is not a lawful merge path and can put you in conflict with traffic or a barrier. If you cannot enter safely, commit to missing the exit rather than making a late, erratic move.
3. How can the mile marker and exit number help if you miss EXIT 225?
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Exit numbers on this interstate correspond to mile markers, so EXIT 225 is near mile 224.5 to 225. If you miss it, continue to the next exit and use the mile markers to judge distance and to navigate back. Do not stop, reverse, or cross the gore. The mile marker also helps you confirm that you are still southbound and how far you are from the next interchange. Treat a missed exit as a routing problem to solve at the next safe exit, not as a reason to make an unsafe maneuver.