What does the Bridge Ices Before Road sign mean?
The Bridge Ices Before Road sign (MUTCD W8-13) is a warning sign under the federal Manual on Uniform Traffic Control Devices, the national standard the states build from. The bridge deck freezes earlier than the surrounding roadway because cold air passes underneath.
Source: MUTCD 11th Edition, Chapter 2C, Table 2C-1, checked 2026-09-09.
What shape and color is the Bridge Ices Before Road sign?
| MUTCD code | W8-13 |
|---|---|
| Group | Warning signs |
| Shape | Diamond |
| Color | Yellow background, black legend and border |
What a diamond means. A warning. It tells you what the road does next and obliges you to do nothing in particular, which is the distinction test writers probe most often.
What yellow means. General warning of a permanent condition ahead.
Warning signs. A diamond reports a condition and orders nothing. What you do about it is left to you, and that gap between a report and an order is what test writers keep probing.
What is the Bridge Ices Before Road sign often mistaken for?
Slippery When Wet (W8-5). This one is specifically about ice forming when the rest of the road is still clear.
|  |
|---|---|
| GroupWarning signs | GroupWarning signs |
| ShapeDiamond | ShapeDiamond |
| ColorYellow background, black legend and border | ColorYellow background, black car-and-skid-marks symbol and border |
| What it meansThe bridge deck freezes earlier than the surrounding roadway because cold air passes underneath. | What it meansGrip falls away sharply on this stretch once it is wet, so brake, steer and accelerate one at a time and none of them hard. |
What does the permit test ask about the Bridge Ices Before Road sign?
This question is from the practice bank, with the answer marked.
Black ice is most likely to form:
- A.In the middle of a straight, open road
- B.On bridges, overpasses and shaded stretches(correct answer)
- C.Only where snow has been cleared
- D.On south-facing hills
Why: A bridge deck loses heat from above and below, so it freezes before the road either side of it. Shaded stretches stay frozen long after open road has thawed.
Source: FHWA road weather management guidance
What are the other warning signs?
All 55 warning signs on one page, or every US road sign by shape and color.
Test yourself on this sign and the rest of the set with a road signs practice test for Florida, Texas or California.
The artwork is the federal design itself, which the manual dedicates to the public domain in MUTCD 11th Edition, Part 1, Section 1D.06, checked 2026-09-09. The Interstate Shield, the 511 pictograph and the National Scenic Byway graphic are named exceptions and are not reproduced anywhere on this site.
Source: Manual on Uniform Traffic Control Devices, 11th Edition. Not affiliated with or endorsed by the Federal Highway Administration or any state agency.