Grid ON40 Band Conditions
Localized HF conditions for Maidenhead locator ON40. Coordinating at 40.50°, 109.00°. Updated with real-time telemetry from NOAA and DX cluster reports.
ON40 conditions are FAIR. Best bands: 10m, 12m, 15m, 17m, 20m. SFI: 137.
From the ON40 operating area, work the 21:32 UTC and 12:10 UTC grayline windows: probe 20m, 30m, and 40m in the 15 minutes either side while the terminator crosses ON40.
10m is the headline band right now, with 20m as the dependable fallback if conditions soften.
This square sits in a mixed-region footprint and is best used as a planning center for portable, field-day, and home-station band decisions.
- Latitude zone
- mid-latitude
- Local phase
- Daylight
- Aurora exposure
- low at this latitude
- Grayline
- 21:32 UTC / 12:10 UTC
- Best high band
- 10m
- Nearest city
- the ON40 operating area
● Local Band Quality Scorings
Use this local score for ON40, then compare the global live ranking oncurrent ham band conditionsbefore changing bands.
● Best DX Windows from ON40 — the ON40 operating area
Great-circle distance, short-path beam heading, the bands most likely open right now from ON40 to each DX region at SFI 137 / Kp 3, and a current verdict. "Open now" means a suitable band is scoring well on that path; "Try ~HH:MM" points at the next far-end grayline. Band picks and status are a planning heuristic, not a measurement.
| Target | Distance | Beam | Bands to try | Status |
|---|---|---|---|---|
| East Asia / Japan | 1,596 mi | 92° | 10m, 15m, 20m | Open now |
| South Asia | 2,214 mi | 244° | 10m, 15m, 20m | Open now |
| Europe | 4,498 mi | 316° | 40m, 20m, 80m | Open now |
| Oceania | 5,533 mi | 145° | 10m, 15m, 20m | Open now |
| North America | 6,686 mi | 21° | 10m, 15m, 20m | Open now |
| Southern Africa | 7,021 mi | 246° | 40m, 20m, 80m | Open now |
| South America | 10,509 mi | 332° | 40m, 20m, 80m | Open now |
● Band-by-Time Plan for ON40
A planning heuristic for the local day at ON40, built from sunrise 21:32 UTC, sunset 12:10 UTC, SFI 137, and Kp 3. Not a measurement — a starting point for where to listen as the day turns.
Grayline enhancement — low bands reach long distances as the terminator passes.
High bands rising with the sun; check 10m for DX.
Peak high-band window — 10m and 15m open widest.
Second grayline peak — 20m holds, then hands off to 40m.
Low bands own the darkness — 40m for DX, 80m regional.
Recent local activity
Spots touching ON40 and the adjacent squares
These are the newest 10m, 15m, and 20m reports where one side of the path sits in ON40, ON41, OM49, ON50, ON30. This gives the page unique, local context instead of a generic solar snapshot.
Top DX targets
Where this grid is reaching right now
Contest preview
Next major contest outlook
No contest event is currently loaded. For planning from ON40, start with 10m EXCELLENT, 15m EXCELLENT, 20m GOOD and keep 20m available as the safest all-around fallback.
Open contest calendarNearby grids
Four adjacent squares for internal path checking
Regional hub links