Changes to 24-hour Forecast Charts

In NWS Service Change Notice 24-38, OPC will expand the 24-hour OPC suite of OPC forecasts to match the longer range (48-, 72-, and 96-hours) products area of coverage (north Atlantic, 22N to 51N, 40W to 98W; north Pacific, 18N to 62N, 108W to 157W). Expansion of the 24-hour geographic area of coverage to match the longer range products has been the most frequent and most consistent request for change through informal customer feedback.

To allow for the geographic area of coverage expansion, OPC will change the 24-hour chart wave height units from feet to meters, matching the longer range products wave units and better meeting international standards. OPC will also remove references to fog on the 24-hour charts to create consistency with the 48-, 72-, and 96-hour chart content and to allow forecasters time to complete the 24-hour information over an expanded area.

A summary of OPC changes are the following:

• Expand the 24-hour suite of OPC products
• Change the 24-hour wave height units to meters
• Remove 24-hour references to fog

Example Set 1

Current 24-hour Surface Chart (Pacific version)

New 24-hour Surface Chart (Pacific version)

Example Set 2

Current 24-hour Wind/Wave Chart (Atlantic version)

New 24-hour Wind/Wave Chart (Atlantic version - Gulf Stream to be included)

Feedback and Comments

You may submit comments about the proposed change on our feedback page.