Viewing archive of Tuesday, 18 April 2006
Solar activity report
Prepared by the NOAA © SWPC and processed by SpaceWeatherLive.com
Joint USAF/NOAA Report of Solar and Geophysical Activity
SDF Number 108 Issued at 2200Z on 18 Apr 2006IA. Analysis of Solar Active Regions and Activity from 17-2100Z to 18-2100Z
IB. Solar Activity Forecast
IIA. Geophysical Activity Summary 17-2100Z to 18-2100Z
IIB. Geophysical Activity Forecast
III. Event Probabilities 19 Apr to 21 Apr
| Class M | 01% | 01% | 01% |
| Class X | 01% | 01% | 01% |
| Proton | 01% | 01% | 01% |
| PCAF | green | ||
IV. Penticton 10.7 cm Flux
Observed 18 Apr 074 Predicted 19 Apr-21 Apr 075/075/075 90 Day Mean 18 Apr 078
V. Geomagnetic A Indices
Observed Afr/Ap 17 Apr 004/006 Estimated Afr/Ap 18 Apr 005/008 Predicted Afr/Ap 19 Apr-21 Apr 005/008-005/008-005/008
VI. Geomagnetic Activity Probabilities 19 Apr to 21 Apr
| A. Middle Latitudes | |||
|---|---|---|---|
| Active | 15% | 15% | 15% |
| Minor storm | 01% | 01% | 01% |
| Major-severe storm | 01% | 01% | 01% |
| B. High Latitudes | |||
|---|---|---|---|
| Active | 20% | 20% | 20% |
| Minor storm | 05% | 05% | 05% |
| Major-severe storm | 01% | 01% | 01% |
All times in UTC
Latest news
X4.0 solar flare
X5.1 solar flare, G4 geomagnetic storm watch
X1.2 solar flare with earth-directed CME
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Latest alerts
Friday, 14 November 2025
21:51 UTC - Solar flare
Moderate M1.33 flare from sunspot region 4274
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Minor R1 radio blackout in progress (≥M1 - current: M1.33)
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| Spotless days | |
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| Monthly mean Sunspot Number | |
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