Viewing archive of Thursday, 21 September 2023
Geophysical report
Solar and Geophysical Activity Summary 2023 Sep 21 0245 UTCPrepared by the NOAA © SWPC and processed by SpaceWeatherLive.com
Joint USAF/NOAA Solar and Geophysical Activity Summary
SGAS Number 264 Issued at 0245Z on 21 Sep 2023 This report is compiled from data received at SWO on 20 SepA. Energetic Events
Begin Max End Rgn Loc Xray Op 245MHz 10cm Sweep 0000 0420 IV 0200 0200 0200 220 0217 0217 0217 230 0323 0323 0323 100 0427 0437 0446 C3.0 110 0450 0450 0450 110 0518 0518 0519 1100 0638 0652 0708 3429 C2.3 270 0956 0956 0956 100 1411 1419 1425 3435 M8.2 1425 1433 II 2317 2321 2325 C2.3 260
B. Proton Events
C. Geomagnetic Activity Summary
D. Stratwarm
E. Daily Indices: (real-time preliminary/estimated values)
10 cm 156 SSN 159 Afr/Ap 015/020 X-ray Background B9.4 Daily Proton Fluence (flux accumulation over 24 hrs) GT 1 MeV 1.2e+05 GT 10 MeV 1.7e+04 p/(cm2-ster-day) (GOES-16 satellite synchronous orbit W75 degrees) Daily Electron Fluence GT 2 MeV 7.10e+07 e/(cm2-ster-day) (GOES-16 satellite synchronous orbit W75 degrees) 3 Hour K-indices Boulder 3 3 4 4 3 3 2 3 Planetary 3 3 4 4 3 4 4 4
F. Comments
None
All times in UTC
The density of the solar wind is moderate (37.3 p/cm3)
Latest news
X1.1 solar flare
Coronal hole faces Earth
Strong G3 geomagnetic storm watch for 23 March
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Latest alerts
18:33 UTC - Solar flare
Moderate M1.31 flare from sunspot region 4055
CME arrival, G3 storm watch
A coronal mass ejection has arrived at our planet. This is the first of possibly two coronal mass ejections that were expected to arrive from filament eruptions on April 12 and 13. The minor G1 geomagnetic storm threshold has already been reached and the NOAA SWPC has a strong G3 geomagnetic storm watch in place for tomorrow, 16 April. Keep an eye on the data here on this website in the hours ahead. There is more action to come!
18:12 UTC - Radio Blackout
Minor R1 radio blackout in progress (≥M1 - current: M1.15)
17:45 UTC - Geomagnetic activity
Minor G1 geomagnetic storm (Kp5) Threshold Reached: 17:32 UTC
17:30 UTC - Geomagnetic activity
Active geomagnetic conditions (Kp4) Threshold Reached: 17:25 UTC
Space weather facts
| Last X-flare | 2025/03/28 | X1.1 |
| Last M-flare | 2025/04/14 | M4.2 |
| Last geomagnetic storm | 2025/04/06 | Kp5 (G1) |
| Spotless days | |
|---|---|
| Last spotless day | 2022/06/08 |
| Monthly mean Sunspot Number | |
|---|---|
| March 2025 | 134.2 -20.4 |
| April 2025 | 128.8 -5.4 |
| Last 30 days | 129.1 -15.1 |