Get current weather conditions for a US location.

Use when: "What's the weather right now?", "How hot is it?", "Is it windy?"

detail="standard": temperature, feels-like, dewpoint (or frost_point when <= 0C), humidity, wind, sky, visibility, pressure. detail="full": adds cloud layers, present weather, raw METAR.

Omit lat/lon to use configured primary location.

units: "us" or "si" for base system, with optional field overrides: "us,pressure:mb,wind:kt". Fields: temperature (f|c), pressure (inhg|mb), wind (mph|kt|kmh|ms), distance (mi|km), accumulation (in|mm|cm).

Get forecast for a US location.

Use when: "What's the forecast?", "Will it rain?", "Weather this week?"

mode="daily": 12-hour day/night periods with narrative forecasts (default). mode="hourly": hour-by-hour temperature, precip chance, wind. mode="raw": gridpoint time-value series for temperature, dewpoint, wind, precip, sky cover.

days (1-7) controls daily mode. hours (1-48) controls hourly mode. Omit lat/lon to use configured primary location.

Note: the main temperature and wind fields in daily/hourly periods come from NWS pre-formatted data and are always in Fahrenheit/mph. The units parameter affects enriched fields: dewpoint/frost_point, feels_like, pressure, and snow/ice accumulation. Use mode="raw" for full unit-agnostic gridpoint data.

units: "us" or "si" for base system, with optional field overrides: "us,pressure:mb,wind:kt". Fields: temperature (f|c), pressure (inhg|mb), wind (mph|kt|kmh|ms), distance (mi|km), accumulation (in|mm|cm).

Get active weather alerts for a US location.

Use proactively at conversation start. Also: "Any warnings?", "Is it safe to travel?"

severity_filter: "Extreme", "Severe", "Moderate", or "Minor" to filter. detail="standard": event, severity, headline, description, instructions. detail="full": adds VTEC codes, polygon geometry, areaDesc, sender.

Omit lat/lon to use configured primary location.

units: accepted for API consistency but does not affect alert output. Alert text is returned as-is from NWS.

Check SPC severe weather outlook for a US location.

Use when: "Severe weather risk?", "Storm outlook?", "Should I worry about storms?"

outlook_type="categorical": risk level (NONE/TSTM/MRGL/SLGT/ENH/MDT/HIGH). outlook_type="tornado"/"wind"/"hail": probabilistic hazard percentage + significant flag.

day: 1=today, 2=tomorrow, 3=day after. Omit lat/lon to use configured primary location.

units: accepted for API consistency but does not affect SPC outlook output. Risk levels and probabilities are unitless.

Get CONUS-wide SPC severe weather risk areas.

Use when: "Any severe weather in the US?", "National storm outlook?"

Returns all active risk areas with human-readable region descriptions (e.g. "central Oklahoma", "northern Texas"). No lat/lon needed.

day: 1=today, 2=tomorrow, 3=day after.

units: accepted for API consistency but does not affect outlook output. Risk levels and region descriptions are unitless.

Get NEXRAD radar info with textual weather summary and clickable links.

Use when: "Show me radar", "What does radar look like?", "Radar imagery?"

Returns a textual summary of current precipitation and near-term outlook (useful when images can't be displayed), plus clickable links to radar imagery the user can open in a browser. Also includes station ID, available products, and latest scan time.

Omit lat/lon to use configured primary location.

units: accepted for API consistency but does not affect radar output. Radar data is imagery-based and unitless.

Get a comprehensive weather briefing for a US location.

The default tool for "What's the weather?" — combines conditions, forecast, alerts, and SPC outlook.

detail="standard": current conditions + today/tonight forecast + alerts + categorical SPC. detail="full": adds probabilistic outlooks (when MRGL+), national outlook, radar, and day 2-3 SPC forecasts.

Omit lat/lon to use configured primary location.

units: "us" or "si" for base system, with optional field overrides: "us,pressure:mb,wind:kt". Fields: temperature (f|c), pressure (inhg|mb), wind (mph|kt|kmh|ms), distance (mi|km), accumulation (in|mm|cm).

Get 500mb upper-air forecast with heights, temperature, wind, and vorticity.

Use when: "What does 500mb look like?", "Where are the troughs?", "Upper-air pattern?", "Jet stream?", "Vorticity?"

500mb (~18,000 ft) is the key level for synoptic-scale pattern recognition:

• Heights reveal troughs (low heights, stormier) and ridges (high heights, calmer)

• Vorticity maxima indicate regions favorable for storm development

• Wind shows the jet stream position and strength

Returns 12-hour time series with height (dam), temperature, wind, and derived relative/absolute vorticity (10^-5 s^-1) from a 5-point finite-difference grid at ~110km spacing.

Not US-only — uses global GFS model data via Open-Meteo. Omit lat/lon to use configured primary location.

units: "us" or "si" for base system, with optional field overrides: "us,pressure:mb,wind:kt". Fields: temperature (f|c), pressure (inhg|mb), wind (mph|kt|kmh|ms), distance (mi|km), accumulation (in|mm|cm).

Get surface analysis or forecast showing fronts, pressure centers, and warm/cold sector.

Use when: "Where are the fronts?", "Am I in the warm sector?", "Surface analysis?", "Where's the nearest low?"

Returns distance and bearing from your location to nearby fronts and pressure centers (highs/lows). For cold fronts, determines whether you're on the warm side (ahead) or cold side (behind).

product="analysis" (default): WPC coded surface analysis (CODSUS) showing current front positions and pressure centers, updated every 3 hours. Includes pressure values on H/L centers. The day parameter is not used. product="forecast": WPC national forecast chart. day: 1=today, 2=tomorrow, 3=day after.

detail="standard": nearest ~5 fronts, ~4 pressure centers, location summary. detail="full": all features with nearest-point coordinates.

scope="local" (default): location summary only references fronts within ~400km — distant fronts are listed but not described as influencing local weather. Use for typical queries about local conditions. scope="all": no distance threshold — location summary always reports warm/cold sector relative to nearest cold front regardless of distance. Use when asking about the broad synoptic pattern.

Note: this tool reports synoptic-scale features (major fronts, pressure centers). Mesoscale boundaries such as outflow boundaries, sea breezes, and moisture gradients are not included in the CODSUS or forecast chart data sources.

Warm/cold sector detection is approximate (geometric heuristic). CONUS coverage only.

Omit lat/lon to use configured primary location.

units: "us" or "si" for base system, with optional field overrides: "us,pressure:mb,wind:kt". Fields: temperature (f|c), pressure (inhg|mb), wind (mph|kt|kmh|ms), distance (mi|km), accumulation (in|mm|cm).