WINDOW

v1

optical / Ka ground window · screening-grade

Optional second pin. Independent screen — not a comparison.

Optical-clear · cloud ≤ and precipitation = 0
MODELED · ERA5 reanalysis · Open-Meteo
No series yet. Enter a point and Go. Open-Meteo ERA5 is fetched in the browser — this page never invents hours.
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Optical hours / year
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All 24h ERA5 hours, including daylight. Not photometric night.
Hours are the ERA5 ~0.25° cell, not the summit or pad.
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Ka-open hours / year
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Rain below the open threshold. Not an availability SLA.
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Ka heavy-fade hours
Risk count · not subtracted from Ka-open
Hours with rain at or above the heavy threshold. Separate from Ka-open.

Screening-grade public reanalysis. Not a link budget. Not underwriting. Not operational weather. Not computed: radio-quiet, elevation mask, ITU-R P.618 rain fade, aerosols — nor seeing, Strehl, dB fade, photometric night, or an availability SLA. Optical hours default to 24h ERA5 hours (cloud and precip), including daylight. Optional night-only is MODELED sun elevation < −0.833° at the ERA5 cell at the GMT hour timestamp, not integrated minutes of darkness — not photometric night. Cloud and rain are ERA5 grid-cell hourly fields, not a telescope or terminal at a pad. Cloud is an instant cell fraction; rain/precip are the preceding-hour sum. On window.tools, ERA5 is fetched via same-origin /api/era5 (Open-Meteo customer archive; the API key is not in this page). Local evaluation may use Open-Meteo’s public archive. Weather data by Open-Meteo.com