Field manual · 11/17

Weather & Sky

Weather and light conditions for the position you are looking at — not just where you are standing. Both tools read the map centre, so you can check the far side of a ridge before you cross it.

the weather forecast

Tools → Weather Forecast gives the forecast for the crosshair position. It is also one tap away from the Position screen, from any pin's details, and from the Navigate sheet — which is how you check conditions at a destination rather than at the start point.

Hourly and daily

Each day is broken into an hourly strip with conditions, temperature, precipitation and wind. Days are labelled Today, Tomorrow and then by date.

Your units

Temperature follows your Temperature Unit, and wind follows the separate Wind Speed setting — so you can read temperature in Celsius and wind in knots, which is what marine and aviation work actually needs.

Derived conditions

The conditions panel adds the numbers that matter in the field: Dew Point and the temperature–dew-point Spread, a Fog Risk read-out (None, Low, Moderate or High, colour-coded), an estimated Cloud Base in your altitude unit, plus Pressure and Cloud Cover. A tight spread with high fog risk is the warning you want before committing to a valley or a flight.

Data comes from the Norwegian Meteorological Institute, which is a global model rather than a national one — so a forecast exists for remote ground as well as for towns.

Free users see today. Pro extends the forecast to ten days.

The forecast needs an internet connection. If it cannot load, the screen says so and offers to try again rather than showing stale numbers as if they were current.

Hourly weather forecast at the map centre position — Weather forecast

sun & moon

Tools → Sun & Moon computes the light for the map-centre position and a date you choose. It is entirely offline — pure astronomy, no network — so it works anywhere, at any time, including in airplane mode.

Pick any date with the date control, or tap Today to jump back.

Live position of the sun and moon

For today, a Now panel shows the current Azimuth and Altitude of both the sun and the moon, refreshed as time passes — the azimuth in your north reference and angle unit. A body below the horizon says so. It is the quick way to know where the sun is right now for shadow, glare or a solar bearing.

What the screen reports
Readout	Meaning
Sun
Sunrise	Upper limb of the sun reaches the horizon
Sunset	Upper limb drops below the horizon
Solar Noon	Sun at its highest — true south or north, and the shortest shadow of the day
Day Length	Sunrise to sunset
Twilight
BMNT	Begin morning nautical twilight — nautical dawn
Civil Dawn	Enough light to work and read without artificial light
Civil Dusk	That light is gone
EENT	End evening nautical twilight — nautical dusk
Astronomical	Full darkness begins and ends
Moon
Moonrise	Moon reaches the horizon
Moonset	Moon drops below it
Illumination	Percentage of the disc lit
Moon age	Days since the new moon, with the phase

reading the twilight times

Twilight is graded by how far the sun is below the horizon, and each band changes what you can actually do.

Civil: Sun 0–6° below. You can read a map and move over ground without a light. The horizon is sharp.
Nautical: Sun 6–12° below. The horizon is still faintly visible against the sky — the band that BMNT and EENT bracket.
Astronomical: Sun 12–18° below. Effectively night; only the brightest stars were visible before this, and now all of them are.

The Sun and Moon screen with sunrise, sunset, twilight times and the moon phase — Sun & Moon

BMNT and EENT are the two times that bound the usable working day in the field. BMNT is when movement can begin under natural light; EENT is when it effectively stops. Planning stand-to, a departure or a link-up around them is more reliable than using sunrise and sunset, which are already too late and too early respectively.

These times shift fast with latitude and season. At high latitude in summer the sun may never reach a band at all, and the screen reflects that rather than inventing a time.

planning with light and weather

Check the destination, not your position. Move the map centre to where you are going before opening either tool. Weather on the lee side of a ridge is not the weather on the windward side.

Combine moon illumination with the terrain tools. A full moon plus a clear forecast is a different night operation from a new moon under cloud — and the viewshed tells you which ground is exposed to that light.

Set the date forward. Sun & Moon works for any date, so you can plan next week's timings now, while you have signal and a desk.

Set the time zone to Zulu in Settings → Formats & Units if your timings will go out over a net or into orders. Every clock time in the app then matches what you transmit. See Settings.

The AR view draws the sun and moon arcs across the real landscape, which is the fastest way to see where the light will actually fall on the ground in front of you. See Terrain Analysis.

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