Viewing archive of Monday, 16 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 16 2200 UTCPrepared by the NOAA © SWPC and processed by SpaceWeatherLive.com
Joint USAF/NOAA Report of Solar and Geophysical Activity
SDF Number 228 Issued at 2200Z on 16 AUG 1999IA. Analysis of Solar Active Regions and Activity from 15-2100Z to 16-2100Z SOLAR ACTIVITY WAS LOW. REGION 8668 (N23E40) PRODUCED
A COUPLE MINOR C-CLASS X-RAY EVENTS AT 16/0034Z AND 16/2029Z. THE
REGION DISPLAYED LITTLE CHANGE SINCE YESTERDAY. NO NEW REGIONS WERE
NUMBERED.
IB. Solar Activity Forecast
SOLAR ACTIVITY IS EXPECTED TO BE LOW.
C-CLASS EVENTS ARE MOST PROBABLE FROM REGION 8668.
IIA. Geophysical Activity Summary 15-2100Z to 16-2100Z
THE GEOMAGNETIC FIELD RANGED FROM QUIET TO MINOR STORM LEVELS. SOLAR
WIND VELOCITIES STARTED TO INCREASE AROUND 16/0400Z AND REACHED OVER
700 KM/S. DENSITY DECREASED AT THE SAME TIME INDICATING A POSSIBLE
HIGH STREAM CORONAL HOLE IMPACTING THE EARTH.
IIB. Geophysical Activity Forecast
THE GEOMAGNETIC FIELD IS
EXPECTED TO BE PREDOMINATELY UNSETTLED TO ACTIVE FOR THE NEXT TWO
DAYS, BECOMING MORE QUIET TO UNSETTLED THE THIRD DAY. THIS
INCREASED GEOMAGNETIC ACTIVITY IS BASED ON THE POSSIBLE CONTINUATION
OF A HIGH SPEED CORONAL HOLE STREAM IN THE SOUTHWEST QUADRANT OF THE
SUN.
III. Event Probabilities 17 AUG to 19 AUG
| Class M | 05% | 05% | 05% |
| Class X | 01% | 01% | 01% |
| Proton | 01% | 01% | 01% |
| PCAF | GREEN | ||
IV. Penticton 10.7 cm Flux
Observed 16 AUG 131 Predicted 17 AUG-19 AUG 135/138/145 90 Day Mean 16 AUG 163
V. Geomagnetic A Indices
OBSERVED AFR/AP 15 AUG 013/015 ESTIMATED AFR/AP 16 AUG 025/035 PREDICTED AFR/AP 17 AUG-19 AUG 015/012-015/017-015/012
VI. Geomagnetic Activity Probabilities 17 AUG to 19 AUG
| A. Middle Latitudes | |||
|---|---|---|---|
| Active | 25% | 25% | 25% |
| Minor storm | 15% | 15% | 10% |
| Major-severe storm | 01% | 01% | 01% |
| B. High Latitudes | |||
|---|---|---|---|
| Active | 35% | 35% | 35% |
| Minor storm | 25% | 20% | 15% |
| Major-severe storm | 05% | 05% | 01% |
All times in UTC
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