GPS Conditions for Field Work
Solar and geomagnetic activity is one outside factor that can reduce satellite navigation accuracy. These are live NOAA readings.
Right now
Kp 2.3 — Quiet (estimate for the 3-hour period starting Thu 6:00 PM UTC)
Normal conditions. GPS and RTK should perform as usual.
NOAA geomagnetic storm scale now: G0 (none).
Last 24 hours and next 24 hours
| Period starting | Kp | Status | |
|---|---|---|---|
| Wed 9:00 PM UTC | 4.7 | Unsettled | observed |
| Thu 12:00 AM UTC | 2.3 | Quiet | observed |
| Thu 3:00 AM UTC | 3.0 | Quiet | observed |
| Thu 6:00 AM UTC | 3.0 | Quiet | observed |
| Thu 9:00 AM UTC | 4.3 | Unsettled | observed |
| Thu 12:00 PM UTC | 4.0 | Unsettled | observed |
| Thu 3:00 PM UTC | 3.7 | Quiet | observed |
| Thu 6:00 PM UTC | 2.3 | Quiet | estimated |
| Thu 9:00 PM UTC | 2.7 | Quiet | estimated |
| Fri 12:00 AM UTC | 2.3 | Quiet | forecast |
| Fri 3:00 AM UTC | 2.7 | Quiet | forecast |
| Fri 6:00 AM UTC | 2.3 | Quiet | forecast |
| Fri 9:00 AM UTC | 2.3 | Quiet | forecast |
| Fri 12:00 PM UTC | 2.0 | Quiet | forecast |
| Fri 3:00 PM UTC | 2.0 | Quiet | forecast |
| Fri 6:00 PM UTC | 2.0 | Quiet | forecast |
Times are UTC (Central Daylight Time is UTC−5, Eastern is UTC−4, Pacific is UTC−7 while daylight saving time is in effect). Source: NOAA Space Weather Prediction Center, updated every few hours.
What affects field GPS accuracy
- Space weather (shown above). Storms disturb the ionosphere that satellite signals cross. Northern states see it first.
- Sky view. Tree lines, buildings, steep terrain and deep draws block satellites and cause multipath errors.
- Correction source. Free satellite corrections (WAAS in the US) are the baseline; RTK and subscription services are tighter. See the sources below for what each provides.
- Time of day and satellite geometry. Accuracy can wander as satellites move; drift over a few hours is normal for lower accuracy tiers.
- Interference. GPS jammers and some radio equipment can disrupt reception. Report suspected interference to the FCC.
Official sources
- NOAA: space weather and GPS systems
- NOAA: what the Kp index means
- FAA: WAAS (the free satellite correction service) and WAAS performance data
- NOAA National Geodetic Survey: CORS station map (reference stations; some states build RTK networks from them)
- GPS.gov: the official US GPS site
This page shows general conditions. It does not measure your receiver's accuracy. Your equipment maker and your correction provider are the authority on your own system. Links last reviewed 2026-10-22.