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Alert Rules Overview

Alert rules define the conditions that trigger notifications. When a condition is met for one of your locations, LMKwhen sends an alert via your configured channels.

Rule types

LMKwhen supports three categories of alert rules:

NWS Watches, Warnings & Advisories

Official alerts issued by the National Weather Service. These are polygon-based — LMKwhen checks whether your location falls within the affected area. Near real-time, typically within minutes of NWS issuance.

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SPC Severe Weather Outlooks

Categorical severe weather outlooks issued by the Storm Prediction Center for Day 1 and Day 2. Useful for advance notice before severe weather days.

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NDFD Gridded Forecast Alerts

Threshold-based alerts on NWS gridded forecast data — temperature, wind, precipitation, snow, humidity, wind chill, and heat index. Fires when a forecast value exceeds your set threshold.

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Alert templates

Not sure where to start? LMKwhen provides templates for common use cases:

  • NWS Watches, Warnings & Advisories — consolidated rule covering all NWS alert types for your locations
  • SPC Outlooks — Moderate+ categorical risk, Day 1 and Day 2
  • Contractor Essentials — wind, heat, and precipitation thresholds common in field work

Apply templates from the Rules page or during onboarding.

How rules apply to locations

Alert rules apply to all of your locations by default. When any location matches the rule's condition, you receive an alert identifying the specific location affected.

Priority and tags

Each rule has a priority (Normal or High) and an optional set of tags. Both control how the alert is routed once it fires, and both live in the Delivery Options step of the rule wizard.

Alert lifecycle

  1. ACTIVE — condition is met, alert is firing
  2. Resolved — condition is no longer met, all-clear notification sent
  3. Subsequent alerts fire if the condition returns or worsens after resolution