Understanding Your Briefing

What it shows

• A short lead line for the kind of hazard (wind, thunderstorms, winter, tropical, or marine)
• The alert name (for example High Wind Warning), where it applies, and when it is in effect in local day-part words
• Each visible alert line ends with its own issuing office
• The Source line lists every unique office from all matched alerts, including ones not shown in the list
• Up to three alerts in the list. When more alerts match, an extra line reads “Plus 2 more from NWS Elko NV” when the hidden alerts add new offices, and otherwise “Plus N more alerts along the route.”
• If an alert has no sender, or only a bare “NWS”, it shows “NWS office not given” and never borrows another alert's office
• When the alerts were fetched: the banner shows “Alerts as of …”. If the latest check did not complete and older alerts are shown, the line reads “Latest storm alert check didn't complete. Showing alerts as of …”

Which alerts count

PlaneWX matches exact NWS CAP event names that can affect flight safety: high wind and extreme wind, dust and blowing dust, flood and flash flood (including Flood Watch), severe thunderstorm and tornado, winter storm / blizzard / ice storm / snow squall / lake-effect snow, winter weather and freezing rain advisories, dense fog and freezing fog, dense smoke, ashfall, extreme cold, hurricane / typhoon / tropical storm, storm surge when it covers your route, and marine gale / storm / hurricane-force wind products. Matching watches, warnings, and advisories on that list are included. Coastal Flood and Lakeshore Flood products are not included (tidal or lakeshore inundation, not flight weather). Cancelled messages and non-Actual statuses are ignored. Expired alerts are ignored.

Matching uses your departure, destination, and points along the route (about every 25 NM on short routes, spaced farther on long ones, up to 12 interior samples). Zone-only NWS products (no polygon, for example many Flood Watches) match when an NWS point query for a route sample returns them. Alerts that include a polygon are also checked against a shared 20 NM corridor around the route line, so small warning footprints between sample points still show, and cells about 30 NM offline do not. Time matching uses the alert onset/ends window (not message expires) with one hour before departure through one hour after arrival.

Flood products are placed by type. Flash Flood Warnings and areal Flood Warnings (rain flooding over an area) are matched at the departure, destination, route samples, and the 20 NM corridor, and use warning styling. Only Flash Flood Warning text mentions runways and visibility. River flood products (NWS river forecast point warnings, watches, advisories, and statements) appear only when they cover the departure or destination airport, as an advisory-style note. River flood products elsewhere along the route are not shown. When the latest NWS alert check could not finish, the banner keeps the alerts from the previous check, and an older saved Flood Warning that has no product type is then shown only at the departure or destination airport, as a river flood note.

Each NWS alert has its own line with its own time window and office. Separate alerts are not combined into one line. The wording follows what the location check found: an alert that covers an airport names the airport, an alert whose area includes part of the route line says it covers part of your route, and a polygon alert that only falls inside the 20 NM corridor says it is within a number of nautical miles of your route.

Each alert line opens to show the NWS source: the NWS headline, the area the alert names (a long area list shows its first part, and Show rest of area opens the rest), when NWS issued it and when the message expires (departure airport local time with zone, and Z), and a link to the alert record on api.weather.gov. Alerts saved before this detail was added may show only the headline and link.

Warnings use the strongest banner styling, watches use a calmer amber style, and advisories use the lightest style. The banner text is specific to the hazard kind (flood, dust, wind, and so on) and does not change the WX Score.