Exit-Only Lane at a Rainy Interstate Split
You are northbound on I-55 approaching a complex interchange in heavy rain at night. You need to continue to Jackson. An overhead green guide sign one mile ahead reads US 49 SOUTH - Hattiesburg - EXIT ONLY above the right lane. At one-half mile, a second sign reads I-55 NORTH - Jackson - 2 LEFT LANES with downward arrows over the two left lanes and an EXIT ONLY panel over the right lane. You are in the center lane. Your GPS says keep left for I-55 north in 800 feet. The right lane is moving slowly, and a tractor-trailer is beside you in the left lane. White pavement arrows in your lane point straight ahead. Rain is reducing visibility, and your wipers are on high.
1. Which lane should you choose for I-55 north, and when should you make the change? Interpret the signs and markings.
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Stay in the center lane. The overhead guide sign and the second sign both show the two left lanes continuing to I-55 north, while the EXIT ONLY panel over the right lane means that lane must exit to US 49 south. The center lane is one of the two continuing lanes, and the white pavement arrow pointing straight ahead confirms that your lane continues. You do not need to move left, and with a tractor-trailer beside you in the left lane, an unnecessary lane change would increase risk in heavy rain. Make any needed lane choice early and smoothly, but here the correct action is to hold the center lane and follow the overhead arrows.
2. The right lane is slow and you are late. Can you use the exit-only lane to pass traffic and then merge back left before the gore? Explain.
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No. The right lane is marked EXIT ONLY by both the overhead panel and the guide sign, so it is a mandatory exit lane, not a passing lane. Using it to gain position and then cutting back across the gore or a solid white line is unsafe and generally prohibited. In rain at night, a last-minute merge near the gore is especially dangerous because drivers in the continuing lanes may not expect a vehicle to re-enter, and the pavement may be slick. If you enter the exit-only lane, you should be prepared to exit. Passing on the right in an exit lane is not a lawful shortcut for being late.
3. If you accidentally take the exit, what is the safest action, and what sign information would you use?
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Continue on the exit ramp and do not stop, reverse, or cross the gore to re-enter the interstate. A missed exit is a routing problem, not an emergency that justifies a dangerous maneuver. Follow the US 49 south guide signs and route markers to the next safe interchange or intersection where you can turn around legally. Use the green guide signs for destination names, the route marker for US 49, and any subsequent entrance signs for I-55 north to re-enter. The extra few minutes are far safer than backing up on a shoulder or making an illegal U-turn.