Viewing archive of Friday, 3 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 03 2200 UTCPrepared by the NOAA © SWPC and processed by SpaceWeatherLive.com
Joint USAF/NOAA Report of Solar and Geophysical Activity
SDF Number 246 Issued at 2200Z on 03 SEP 1999IA. Analysis of Solar Active Regions and Activity from 02-2100Z to 03-2100Z SOLAR ACTIVITY WAS LOW WITH ONLY LOW LEVEL C-CLASS
X-RAY EVENTS OBSERVED DURING THE PERIOD. THE LASCO SPACECRAFT
OBSERVED A SERIES OF PARTIAL HALO CME EVENTS FROM YESTERDAY THROUGH
EARLY TODAY. THE FIRST EVENT BEGAN AT 02/1530Z OFF THE SE LIMB WITH
INDICATIONS OF IT BEING A BACKSIDE EVENT, THE SECOND BEGAN AT
02/1630Z OVER THE SOUTH POLE WITH NO OBVIOUS SOURCE, AND THE THIRD
WAS OBSERVED AT 03/0006Z. THE EIT IMAGES INDICATED THE SOURCE OF
THIS EVENT AS REGION 8679 (S36W41). A TYPE IV RADIO SWEEP WAS
OBSERVED AT 03/0001Z WITH NO OPTICAL OR X-RAY ASSOCIATED. A NEW
REGION WAS NUMBERED TODAY AS REGION 8688 (S24E14).
IB. Solar Activity Forecast
SOLAR ACTIVITY IS EXPECTED TO BE LOW
WITH THE POSSIBILITY OF ISOLATED M-CLASS X-RAY FLARES.
IIA. Geophysical Activity Summary 02-2100Z to 03-2100Z
THE GEOMAGNETIC FIELD WAS AT QUIET TO MINOR STORM CONDITIONS DURING
THE PERIOD. THE GREATER THAN 2 MEV ELECTRON FLUX AT GEOSYNCHRONOUS
ORBIT WAS AT HIGH LEVELS THROUGH THE PERIOD.
IIB. Geophysical Activity Forecast
THE GEOMAGNETIC FIELD IS
EXPECTED TO BE QUIET TO UNSETTLED CONDITIONS THE FIRST TWO DAYS OF
THE FORECAST PERIOD. THE THIRD DAY MAY EXPERIENCE ACTIVE TO
NEAR-STORM LEVEL CONDITIONS DUE TO CME ACTIVITY OF THE PAST TWO
DAYS.
III. Event Probabilities 04 SEP to 06 SEP
| Class M | 30% | 30% | 30% |
| Class X | 10% | 10% | 10% |
| Proton | 05% | 05% | 05% |
| PCAF | GREEN | ||
IV. Penticton 10.7 cm Flux
Observed 03 SEP 139 Predicted 04 SEP-06 SEP 135/130/130 90 Day Mean 03 SEP 168
V. Geomagnetic A Indices
OBSERVED AFR/AP 02 SEP 011/011 ESTIMATED AFR/AP 03 SEP 020/017 PREDICTED AFR/AP 04 SEP-06 SEP 010/012-010/010-020/015
VI. Geomagnetic Activity Probabilities 04 SEP to 06 SEP
| A. Middle Latitudes | |||
|---|---|---|---|
| Active | 15% | 15% | 25% |
| Minor storm | 10% | 10% | 15% |
| Major-severe storm | 05% | 05% | 10% |
| B. High Latitudes | |||
|---|---|---|---|
| Active | 20% | 20% | 30% |
| Minor storm | 15% | 15% | 20% |
| Major-severe storm | 05% | 05% | 10% |
All times in UTC
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