Viewing archive of Sunday, 5 September 1999
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 1999 Sep 05 2200 UTCPrepared by the NOAA © SWPC and processed by SpaceWeatherLive.com
Joint USAF/NOAA Report of Solar and Geophysical Activity
SDF Number 248 Issued at 2200Z on 05 SEP 1999IA. Analysis of Solar Active Regions and Activity from 04-2100Z to 05-2100Z
SOLAR ACTIVITY HAS BEEN LOW. REGION 8681 (N21 ON WEST
LIMB) PRODUCED TODAY'S ONLY C-CLASS EVENT, A C2/SF AT 0539Z. NEW
REGION 8689 (N18W05) EMERGED ON THE DISK TODAY AND WAS GROWING
STEADILY. REGION 8682 (N18W28) HAS SOME MAGNETIC COMPLEXITY, BUT
WAS QUIET AND STABLE.
IB. Solar Activity Forecast
SOLAR ACTIVITY IS EXPECTED TO BE LOW
FOR THE NEXT THREE DAYS.
IIA. Geophysical Activity Summary 04-2100Z to 05-2100Z
THE GEOMAGNETIC FIELD WAS QUIET TO UNSETTLED. ENERGETIC ELECTRON FLUX
AT GEOSYNCHRONOUS ORBIT ATTAINED HIGH LEVELS DURING THE PAST 24
HOURS.
IIB. Geophysical Activity Forecast
THE GEOMAGNETIC FIELD IS
EXPECTED TO BE UNSETTLED TO ACTIVE FOR THE NEXT 24-36 HOURS. ACTIVE
CONDITIONS ARE POSSIBLE TOMORROW AS A RESPONSE TO RECENT CORONAL
MASS EJECTION EVENTS. ENHANCED ACTIVITY MAY LINGER PARTWAY INTO THE
SECOND DAY, BUT PREDOMINANTLY UNSETTLED CONDITIONS ARE EXPECTED TO
PREVAIL ON THE SECOND AND THIRD DAYS.
III. Event Probabilities 06 SEP to 08 SEP
| Class M | 05% | 05% | 05% |
| Class X | 01% | 01% | 01% |
| Proton | 01% | 01% | 01% |
| PCAF | GREEN | ||
IV. Penticton 10.7 cm Flux
Observed 05 SEP 122 Predicted 06 SEP-08 SEP 120/115/115 90 Day Mean 05 SEP 167
V. Geomagnetic A Indices
OBSERVED AFR/AP 04 SEP 011/015 ESTIMATED AFR/AP 05 SEP 008/012 PREDICTED AFR/AP 06 SEP-08 SEP 020/015-015/015-010/012
VI. Geomagnetic Activity Probabilities 06 SEP to 08 SEP
| A. Middle Latitudes | |||
|---|---|---|---|
| Active | 35% | 20% | 05% |
| Minor storm | 15% | 10% | 05% |
| Major-severe storm | 10% | 10% | 01% |
| B. High Latitudes | |||
|---|---|---|---|
| Active | 35% | 20% | 15% |
| Minor storm | 20% | 15% | 05% |
| Major-severe storm | 05% | 05% | 01% |
All times in UTC
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