Viewing archive of Sunday, 15 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 15 2200 UTCPrepared by the NOAA © SWPC and processed by SpaceWeatherLive.com
Joint USAF/NOAA Report of Solar and Geophysical Activity
SDF Number 227 Issued at 2200Z on 15 AUG 1999IA. Analysis of Solar Active Regions and Activity from 14-2100Z to 15-2100Z SOLAR ACTIVITY WAS LOW. REGION 8662 (S15W59) CONTINUES
TO DECAY AND PRODUCED THE LARGEST FLARE SINCE YESTERDAY, A C4/1N AT
15/0123UT. REGION 8668 (N22E54) PRODUCED A FEW SUBFLARES BUT NOTHING
SIGNIFICANT. NEITHER REGION IS MAGNETICALLY COMPLEX. NEW REGIONS
8670 (S12W23) AND 8671 (S09W13) WERE NUMBERED.
IB. Solar Activity Forecast
SOLAR ACTIVITY IS EXPECTED TO BE LOW.
C-CLASS FLARES ARE POSSIBLE IN REGIONS 8662 AND 8668.
IIA. Geophysical Activity Summary 14-2100Z to 15-2100Z
THE GEOMAGNETIC FIELD WAS QUIET TO ACTIVE. ACTIVITY IS IN RESPONSE TO
A GRADUAL INCREASE IN THE SOLAR WIND SPEED AND IMF INTENSITY AND
VARIABILITY.
IIB. Geophysical Activity Forecast
THE GEOMAGNETIC FIELD IS
EXPECTED TO BE MOSTLY UNSETTLED FOR THE DURATION OF THE FORECAST
PERIOD.
III. Event Probabilities 16 AUG to 18 AUG
| Class M | 05% | 05% | 05% |
| Class X | 01% | 01% | 01% |
| Proton | 01% | 01% | 01% |
| PCAF | GREEN | ||
IV. Penticton 10.7 cm Flux
Observed 15 AUG 131 Predicted 16 AUG-18 AUG 132/134/136 90 Day Mean 15 AUG 163
V. Geomagnetic A Indices
OBSERVED AFR/AP 14 AUG 005/005 ESTIMATED AFR/AP 15 AUG 012/010 PREDICTED AFR/AP 16 AUG-18 AUG 015/012-015/010-015/015
VI. Geomagnetic Activity Probabilities 16 AUG to 18 AUG
| A. Middle Latitudes | |||
|---|---|---|---|
| Active | 15% | 15% | 15% |
| Minor storm | 05% | 05% | 05% |
| 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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