Viewing archive of Tuesday, 17 July 2001
Solar activity report
Any mentioned solar flare in this report has a scaling factor applied by the Space Weather Prediction Center (SWPC). Because of the SWPC scaling factor, solar flares are reported as 42% smaller than for the science quality data. The scaling factor has been removed from our archived solar flare data to reflect the true physical units.
Report of Solar-Geophysical Activity 2001 Jul 17 2200 UTCPrepared by the NOAA © SWPC and processed by SpaceWeatherLive.com
Joint USAF/NOAA Report of Solar and Geophysical Activity
SDF Number 198 Issued at 2200Z on 17 Jul 2001IA. Analysis of Solar Active Regions and Activity from 16-2100Z to 17-2100Z Solar activity was low. The largest event was a C2/Sf
flare from Region 9539 (S18W42) at 17/1024 UTC. No new regions were
numbered today.
IB. Solar Activity Forecast
Solar activity is expected to be low
to moderate.
IIA. Geophysical Activity Summary 16-2100Z to 17-2100Z
The geomagnetic field was unsettled to active. Solar wind speeds
reached 600 to 700 km/s due to high-speed streaming from a recurrent
coronal hole.
IIB. Geophysical Activity Forecast
The geomagnetic field is
expected to be quiet to active during the forecast period. The
effects of the coronal hole will diminish over day one. This will
be followed by a brief interlude while another coronal hole moves
into a geo-effective position for the second and third days.
III. Event Probabilities 18 Jul to 20 Jul
| Class M | 40% | 40% | 40% |
| Class X | 01% | 01% | 01% |
| Proton | 01% | 01% | 01% |
| PCAF | green | ||
IV. Penticton 10.7 cm Flux
Observed 17 Jul 146 Predicted 18 Jul-20 Jul 150/150/150 90 Day Mean 17 Jul 159
V. Geomagnetic A Indices
Observed Afr/Ap 16 Jul 011/017 Estimated Afr/Ap 17 Jul 018/018 Predicted Afr/Ap 18 Jul-20 Jul 010/012-010/010-010/010
VI. Geomagnetic Activity Probabilities 18 Jul to 20 Jul
| A. Middle Latitudes | |||
|---|---|---|---|
| Active | 20% | 20% | 20% |
| Minor storm | 05% | 05% | 05% |
| Major-severe storm | 01% | 01% | 01% |
| B. High Latitudes | |||
|---|---|---|---|
| Active | 25% | 25% | 25% |
| Minor storm | 10% | 10% | 10% |
| Major-severe storm | 01% | 01% | 01% |
All times in UTC
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