Aligning Call-Outs With NWS Warning Criteria: A Depot Reference

Standard in brief: National Weather Service forecast offices publish local criteria for when they issue winter products such as warnings and advisories. Why it matters: if your call-out triggers refer to those products, you need the thresholds for your own office, because they are local. I read one office’s page, Wilmington, Ohio, on 24 October 2026, to show the kind of information published. Do not use its numbers for your area.

What one office’s page says

The NWS Wilmington, OH office’s “Local Product Criteria – Winter” page lists, for example:

• Winter Storm Warning: event total snow or sleet accumulation thresholds, shown with more than one value (6, 5 and 4 inches) on the page, which suggests different thresholds for different parts of the office’s area.
• Winter Weather Advisory: snow or sleet accumulation thresholds (3 and 2 inches shown), or ice under 1/4 inch, or other conditions expected to impact travel.
• Ice Storm Warning: event total ice accumulation of 1/4 inch or greater.
• Blizzard Warning: sustained winds or frequent gusts of 35 mph or greater with falling or blowing snow and visibility of 1/4 mile or less for at least 3 hours.
• Snow Squall Warning: intense, short periods of moderate to heavy snow with gusty winds and greatly reduced visibility.
• Cold products: thresholds based on air temperature or wind chill.

How a depot can use this

The criteria are a trigger, and a trigger is only useful if it maps to an action.

1. Find your forecast office and open its criteria page.
2. Copy the thresholds that apply to your county into a one-page reference, with the date and URL.
3. Decide, in your own procedure, what each product triggers, such as alerts, call-outs or staffing.
4. Re-check the page each autumn, because offices can change criteria.

Limits

The criteria describe weather, not road conditions.

• A product is a forecast, and a warning does not tell you what your roads will do.
• The numbers above belong to one office; yours may differ.
• Your own trigger may reasonably be earlier or later than the NWS product.

Some depots also keep a column for what their own sensors or patrols showed at the time of each product. Over a few seasons, that comparison tells you whether your triggers are well matched to the warnings, or whether you should act earlier or later than the product.

Boundary: Thresholds are from one office as read on 24 October 2026 and are shown only as an example; use your own office’s current page.