The W3-1 Stop Ahead sign is a California MUTCD warning sign. It is shown here as an educational reference with the official FHWA Standard Highway Signs layout and California sizing guidance.
MUTCD-style sign reference illustration. Always verify against the official CA MUTCD and Caltrans sign charts.
| Sign code | W3-1 |
|---|---|
| Federal code | W3-1 |
| Name | Stop Ahead |
| Category | Warning Signs |
| Shape | Diamond |
| Color | Yellow background |
| California status | Used in California per CA MUTCD |
| Typical CA minimum size | 48" × 48" on conventional roads; 60" × 60" on expressways and freeways |
The official dimensioned layout drawings below show the exact border widths, legend and letter heights, spacing, corner radius, and the standard sizes used to fabricate W3-1. Use them to confirm sign sizing for your road type before finalizing a traffic control plan.
| Application | Size |
|---|---|
| Conventional roads | 48" × 48" |
| Expressways & freeways | 60" × 60" |
Source: CA MUTCD Part 6F (TTC) & Part 2C (warning sign design). Confirm the exact size for your road type and speed against the current CA MUTCD and the official layout drawing.
Layout drawing extracted from the FHWA Standard Highway Signs (public domain). Verify exact dimensions and sizes against the current CA MUTCD, Caltrans sign specifications, and Standard Plans for your application.
Download this sign or open the official MUTCD reference.
Official source: FHWA Standard Highway Signs, 2024 (11th Edition) — Warning & Temporary Traffic Control signs.
This is an educational reference. Verify sign use, size, placement, and application against the current CA MUTCD, Caltrans sign specifications, Standard Plans, and the reviewing agency. Official source links are gathered in one place.
View official sourcesThe W3-1 Stop Ahead sign is a California MUTCD warning sign. It is shown here as an educational reference with the official FHWA Standard Highway Signs layout and California sizing guidance.
The W3-1 Stop Ahead sign is a California MUTCD warning sign. It is shown here as an educational reference with the official FHWA Standard Highway Signs layout and California sizing guidance. In the field, W3-1 Stop Ahead is typically positioned at the advance warning area, ahead of the work. Common deployments include used where stop ahead conditions apply on a California project; selected and sized per the CA MUTCD and the roadway type; coordinated with the overall traffic control plan and permit. Always confirm its size, retroreflective sheeting, spacing, and placement against the CA MUTCD 2026 and the reviewing agency before finalizing the traffic control plan.
W3-1 Stop Ahead is used in California per the CA MUTCD. Confirm its size, retroreflective sheeting, placement, and spacing against the CA MUTCD 2026 and the reviewing agency before finalizing the traffic control plan.
Common field deployments
Agency review note
StreetsLA, LA County DPW, and Caltrans District 7 may require larger sizes or additional devices. Verify with the reviewing agency before finalizing the TCP.
Typical minimum: 48" × 48" on conventional roads; 60" × 60" on expressways and freeways.
Sizes are CA MUTCD minimums and vary by roadway classification and speed. Verify against the CA MUTCD 2026 (CA MUTCD Part 6 (Temporary Traffic Control), Chapter 6F; warning-sign design in Part 2C), Caltrans sign specifications, and the reviewing agency.
Where it sits: Advance warning area, ahead of the work.
CA MUTCD reference: CA MUTCD Part 6 (Temporary Traffic Control), Chapter 6F; warning-sign design in Part 2C.
In Los Angeles, this sign must conform to CA MUTCD 2026. Work in City of LA right-of-way is reviewed by StreetsLA and the Bureau of Engineering (BOE); state highways in LA County are permitted and reviewed by Caltrans District 7; county roads are permitted by LA County DPW. Sizes, retroreflectivity, and placement must meet CA MUTCD minimums — local agencies may require larger signs based on roadway class, speed, pedestrian volume, and proximity to schools or transit.
Confirm W3-1 Stop Ahead is the correct designation, size, and placement for the condition. Public Ready can review sign selection against the TCP and agency requirements.
These signs are typically deployed alongside W3-1 on a California TCP.
Need a Stop Ahead (W3-1) sign for a California work zone? Public Ready can help you rent or purchase project-ready signs.
Free official resource — opens official government website
Free official resource — opens official government website
Free official resource — opens official government website
Free official resource — opens official government website
Educational reference only. This is not an official Caltrans, FHWA, or local agency publication and is not legal or engineering advice. Always verify sign selection, size, placement, spacing, and application against the current CA MUTCD 2026, Caltrans sign specifications, Standard Plans, project documents, and the reviewing agency’s requirements.
To understand the bigger picture around permits, agency review, lane closures, and pedestrian access for work zones using W3-1 Stop Ahead, visit WorkZoneCompliance.com.
Public Ready can help with W3-1 Stop Ahead — including sign rental or purchase, California-compliant signs and traffic control plan support, and agency-review support for Caltrans District 7, the City of Los Angeles, and LA County.
