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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 four 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, probabilistic, fire weather, and dry thunderstorm outlooks issued by the Storm Prediction Center for Day 1 through Day 3. Useful for advance notice before severe weather and fire-danger days.

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WPC Rainfall & Winter Outlooks​

Flash-flood (Excessive Rainfall) and winter precipitation probability outlooks issued by the Weather Prediction Center. Polygon-based, Day 1 through Day 7 depending on product. The best advance signal for flash-flood and plowable-snow/damaging-ice days.

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NDFD Gridded Forecast Alerts​

Threshold-based alerts on NWS gridded forecast data — temperature, apparent temperature, heat risk, heat stress (WBGT), wind, precipitation, snow, ice, humidity, and tropical-cyclone threat grids. Fires when a forecast value crosses 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