What causes "wttr.in returned no forecast for "${location}"." in jackwener/OpenCLI?

Retry with a more canonical location string (e.g. 'Paris' or '48.85,2.35')

jackwener/OpenCLI · error · EmptyResultError

wttr.in returned no forecast for "${location}".

Error message

wttr.in returned no forecast for "${location}".

What it means

This EmptyResultError is thrown when wttr.in responds successfully but its j1 JSON payload contains no `weather` array (or an empty one) for the requested location. It signals a successful HTTP exchange that yielded no forecast data rather than a network or HTTP failure.

Source

Thrown at clis/wttr/forecast.js:46

            help: 'Max forecast days (1-3, wttr.in caps the response at 3 days)',
        },
    ],
    columns: [
        'rank', 'date', 'minTempC', 'maxTempC', 'avgTempC',
        'minTempF', 'maxTempF', 'avgTempF',
        'sunHour', 'totalSnowCm', 'uvIndex',
        'description', 'sunrise', 'sunset',
    ],
    func: async (args) => {
        const location = requireString(args.location, 'location');
        const days = Number(args.days ?? 3);
        if (!Number.isInteger(days) || days < 1 || days > 3) {
            throw new ArgumentError('--days must be an integer between 1 and 3 (wttr.in caps the free-tier forecast at 3 days)');
        }
        const body = await wttrFetch(location, 'wttr forecast');
        const list = Array.isArray(body?.weather) ? body.weather : [];
        if (!list.length) {
            throw new EmptyResultError('wttr forecast', `wttr.in returned no forecast for "${location}".`);
        }
        return list.slice(0, days).map((day, i) => {
            // wttr.in's day-summary uses the noon hourly slot for "main" description.
            // Index 4 = 12:00 in their 3-hour-step hourly array.
            const noon = Array.isArray(day.hourly) && day.hourly[4] ? day.hourly[4] : day.hourly?.[0] ?? {};
            const astro = Array.isArray(day.astronomy) ? day.astronomy[0] : null;
            return {
                rank: i + 1,
                date: day.date ?? null,
                minTempC: day.mintempC != null ? Number(day.mintempC) : null,
                maxTempC: day.maxtempC != null ? Number(day.maxtempC) : null,
                avgTempC: day.avgtempC != null ? Number(day.avgtempC) : null,
                minTempF: day.mintempF != null ? Number(day.mintempF) : null,
                maxTempF: day.maxtempF != null ? Number(day.maxtempF) : null,
                avgTempF: day.avgtempF != null ? Number(day.avgtempF) : null,
                sunHour: day.sunHour != null ? Number(day.sunHour) : null,
                totalSnowCm: day.totalSnow_cm != null ? Number(day.totalSnow_cm) : null,
                uvIndex: day.uvIndex != null ? Number(day.uvIndex) : null,

View on GitHub (pinned to 49907e53dc)

Solutions

Retry with a more canonical location string (e.g. 'Paris' or '48.85,2.35')
Check wttr.in availability/rate limiting with curl 'https://wttr.in/Paris?format=j1'
Handle EmptyResultError in your caller and surface a friendly message

Example fix

// before
await forecast({ location: 'Nowhereville XYZ' });
// after
await forecast({ location: 'Paris' }); // or lat,lon pair

Defensive patterns

Strategy: try-catch

Validate before calling

const body = await wttrFetch(location, 'wttr forecast');
if (!Array.isArray(body?.weather) || body.weather.length === 0) {
  throw new Error(`no forecast data for ${location}`);
}

Type guard

function hasForecast(body) {
  return typeof body === 'object' && body !== null &&
    Array.isArray(body.weather) && body.weather.length > 0;
}

Try / catch

try {
  result = await forecast({ location });
} catch (err) {
  if (err instanceof EmptyResultError) {
    console.warn(`No forecast for "${location}"; try a nearby major city.`);
  } else throw err;
}

Prevention

Prefer well-known city names or lat,lon coordinates
Check the raw wttr.in response for the location before relying on it
Treat empty weather arrays as an expected outcome and fall back to another provider

When it happens

Trigger: wttrFetch returns a body where body.weather is missing, not an array, or []; the command then throws EmptyResultError('wttr forecast', ...).

Common situations: wttr.in returning a degenerate 200 response for obscure locations; API schema changes; rate-limited or cached empty responses; typos in location that still geocode to nothing.

Related errors

AI-assisted analysis of jackwener/OpenCLI@49907e53dc (2026-08-29). Data as JSON: /api/errors/f419ff70e673a68f. Report an issue: GitHub.