Viewing archive of Thursday, 12 August 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 Aug 12 2200 UTCPrepared by the NOAA © SWPC and processed by SpaceWeatherLive.com
Joint USAF/NOAA Report of Solar and Geophysical Activity
SDF Number 224 Issued at 2200Z on 12 AUG 1999IA. Analysis of Solar Active Regions and Activity from 11-2100Z to 12-2100Z SOLAR ACTIVITY WAS LOW. ONLY A FEW LOW-LEVEL C-CLASS
EVENTS OCCURRED. A LONG-DURATION C1 AT 11/2229UT WAS ASSOCIATED WITH
AN ERUPTIVE PROMINENCE ON THE WEST LIMB NEAR NW28. REGION 8662
(S16W19) IS THE MOST COMPLEX REGION ON THE DISK AS A DECAYING E-TYPE
GROUP. THIS REGION HAS PRODUCED ONLY MINOR FLARES SINCE YESTERDAY.
NEW REGIONS NUMBERED INCLUDE 8666 (N14W59) AND 8667 (N23E69).
IB. Solar Activity Forecast
SOLAR ACTIVITY IS EXPECTED TO BE LOW.
C-CLASS FLARES ARE POSSIBLE IN REGIONS 8662 AND 8667.
IIA. Geophysical Activity Summary 11-2100Z to 12-2100Z
THE GEOMAGNETIC FIELD WAS QUIET TO UNSETTLED.
IIB. Geophysical Activity Forecast
THE GEOMAGNETIC FIELD IS
EXPECTED TO BE QUIET TO UNSETTLED.
III. Event Probabilities 13 AUG to 15 AUG
| Class M | 05% | 05% | 05% |
| Class X | 01% | 01% | 01% |
| Proton | 01% | 01% | 01% |
| PCAF | GREEN | ||
IV. Penticton 10.7 cm Flux
Observed 12 AUG 123 Predicted 13 AUG-15 AUG 122/124/126 90 Day Mean 12 AUG 164
V. Geomagnetic A Indices
OBSERVED AFR/AP 11 AUG 006/008 ESTIMATED AFR/AP 12 AUG 008/007 PREDICTED AFR/AP 13 AUG-15 AUG 008/008-008/006-008/006
VI. Geomagnetic Activity Probabilities 13 AUG to 15 AUG
| A. Middle Latitudes | |||
|---|---|---|---|
| Active | 15% | 15% | 15% |
| Minor storm | 01% | 01% | 01% |
| Major-severe storm | 01% | 01% | 01% |
| B. High Latitudes | |||
|---|---|---|---|
| Active | 15% | 15% | 15% |
| Minor storm | 05% | 05% | 05% |
| Major-severe storm | 01% | 01% | 01% |
All times in UTC
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