Viewing archive of Tuesday, 11 August 1998
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 1998 Aug 11 2200 UTCPrepared by the NOAA © SWPC and processed by SpaceWeatherLive.com
Joint USAF/NOAA Report of Solar and Geophysical Activity
SDF Number 223 Issued at 2200Z on 11 AUG 1998IA. Analysis of Solar Active Regions and Activity from 10-2100Z to 11-2100Z SOLAR ACTIVITY WAS LOW. ISOLATED, MOSTLY OPTICALLY
UNCORROLATED MINOR C-CLASS FLARES OCCURRED EARLY IN THE PERIOD.
REGION 8293 (S22W44) IS SLOWLY DECAYING BUT STILL MAINTAINS MODERATE
MAGNETIC COMPLEXITY IN A BETA-GAMMA CONFIGURATION. REGION 8299
(N15E26) CONTINUES TO EXHIBIT OCCASIONAL PLAGE FLUCTUATIONS AND
SURGING BUT HAS OTHERWISE BEEN QUIET. REGION 8298 (N20W38)
EXPERIENCED MINOR GROWTH AND PRODUCED A C1/SF AT 10/2142Z. REMAINING
REGIONS HAVE BEEN QUIET.
IB. Solar Activity Forecast
SOLAR ACTIVITY IS EXPECTED TO BE LOW
TO MODERATE. REGIONS 8293 AND 8299 ARE SHOWING SOME SLIGHT DECAY BUT
ARE STILL CAPABLE OF PRODUCING ISOLATED M-CLASS ACTIVITY.
IIA. Geophysical Activity Summary 10-2100Z to 11-2100Z
THE GEOMAGNETIC FIELD WAS QUIET TO UNSETTLED.
IIB. Geophysical Activity Forecast
THE GEOMAGNETIC FIELD IS
EXPECTED TO BECOME ACTIVE IN THE NEXT 12 HOURS IN RESPONSE TO THE
LARGE DSF/CME OBSERVED ON 08 AUG. CONDITIONS ARE EXPECTED TO RETURN
TO QUIET TO UNSETTLED BY DAY 2 AND 3.
III. Event Probabilities 12 AUG to 14 AUG
| Class M | 30% | 25% | 25% |
| Class X | 05% | 05% | 05% |
| Proton | 05% | 05% | 05% |
| PCAF | GREEN | ||
IV. Penticton 10.7 cm Flux
Observed 11 AUG 150 Predicted 12 AUG-14 AUG 150/145/145 90 Day Mean 11 AUG 111
V. Geomagnetic A Indices
OBSERVED AFR/AP 10 AUG 013/014 ESTIMATED AFR/AP 11 AUG 009/010 PREDICTED AFR/AP 12 AUG-14 AUG 025/025-015/015-005/008
VI. Geomagnetic Activity Probabilities 12 AUG to 14 AUG
| A. Middle Latitudes | |||
|---|---|---|---|
| Active | 40% | 20% | 10% |
| Minor storm | 25% | 10% | 05% |
| Major-severe storm | 05% | 01% | 01% |
| B. High Latitudes | |||
|---|---|---|---|
| Active | 50% | 25% | 15% |
| Minor storm | 35% | 15% | 10% |
| Major-severe storm | 10% | 05% | 01% |
All times in UTC
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