Monthly field plan

September 2026 moonbow

The official window runs September 24–28. The Moon shifts northward each evening, so the effective tree-lined skyline becomes progressively more important.

Arrival datePark timeMoon at startEffective skyline
Thursday, Sep 2420:3022:3021.9° at 118°13.9°
Friday, Sep 2521:0023:0023.6° at 110°16.1°
Saturday, Sep 2621:3023:3024.9° at 102°18.4°
Sunday, Sep 2722:0000:0025.2° at 94°20.6°
Monday, Sep 2822:3000:3024.3° at 85°22.3°

What changes as the date approaches

More than seven days out, the tool keeps weather in planning mode. At seven days it adds the NWS grid. Inside three hours it gives NOAA’s GOES cloud mask and surface observations more influence. The Moon geometry itself does not change between those modes.