Viewing archive of Saturday, 10 April 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 Apr 10 2200 UTCPrepared by the NOAA © SWPC and processed by SpaceWeatherLive.com
Joint USAF/NOAA Report of Solar and Geophysical Activity
SDF Number 100 Issued at 2200Z on 10 APR 1999IA. Analysis of Solar Active Regions and Activity from 09-2100Z to 10-2100Z SOLAR ACTIVITY HAS BEEN LOW. THE MOST INTERESTING
ACTIVITY HAS BEEN IN REGION 8508 (N23W14) A SMALL BUT COMPLEX BETA
GAMMA REGION WITH A CONVOLUTED NEUTRAL LINE EXTENDING THROUGH THE
REGION. IT HAS PRODUCED SEVERAL SMALL FLARES RANGING UP TO CLASS C
INTENSITY. OTHER REGIONS ARE STABLE OR DECLINING.
IB. Solar Activity Forecast
SOLAR ACTIVITY IS EXPECTED TO REMAIN
LOW.
IIA. Geophysical Activity Summary 09-2100Z to 10-2100Z
THE GEOMAGNETIC FIELD HAS BEEN QUIET TO UNSETTLED. ACE SOLAR WIND
DATA INDICATES EARTH MAY BE IN A HIGH SPEED STREAM. SOLAR WIND
VELOCITY HAS INCREASED MODERATELY ALONG WITH THE TEMPERATURE WHILE
THE DENSITY HAS DECREASED OVER THE PAST 12 HOURS. THE SOURCE IS
INDEFINITE BUT MAY BE A SMALL, POORLY-DEFINED CORONAL HOLE VISIBLE
AROUND N22W30. ENERGETIC ELECTRON FLUXES AT GEOSYNCHRONOUS ORBIT
HAVE REMAINED AT MODERATE LEVELS.
IIB. Geophysical Activity Forecast
THE GEOMAGNETIC FIELD IS
EXPECTED TO BE UNSETTLED TO ACTIVE THROUGH THE NEXT 24 HOURS.
III. Event Probabilities 11 APR to 13 APR
| Class M | 25% | 25% | 25% |
| Class X | 05% | 05% | 05% |
| Proton | 05% | 05% | 05% |
| PCAF | GREEN | ||
IV. Penticton 10.7 cm Flux
Observed 10 APR 136 Predicted 11 APR-13 APR 132/130/128 90 Day Mean 10 APR 135
V. Geomagnetic A Indices
OBSERVED AFR/AP 09 APR 007/005 ESTIMATED AFR/AP 10 APR 014/010 PREDICTED AFR/AP 11 APR-13 APR 012/010-010/010-010/008
VI. Geomagnetic Activity Probabilities 11 APR to 13 APR
| A. Middle Latitudes | |||
|---|---|---|---|
| Active | 15% | 14% | 15% |
| Minor storm | 07% | 08% | 06% |
| Major-severe storm | 03% | 03% | 01% |
| B. High Latitudes | |||
|---|---|---|---|
| Active | 13% | 11% | 13% |
| Minor storm | 07% | 07% | 07% |
| Major-severe storm | 04% | 04% | 03% |
Latest news
Monday, 22 April 2024
Lot's of sunspots! Big chance for major flare activity?
Saturday, 23 March 2024
X1.1 solar flare with earth-directed CME
Wednesday, 20 March 2024
Sunspot region 3615, G1 watch
Latest forum messages
AR3654 24Unspecified geomagnetic activity 954Unproven theories 342Changelog/Featurelog 154What are these long and thin eruptions? 9
More topicsSupport SpaceWeatherLive.com!
A lot of people come to SpaceWeatherLive to follow the Sun's activity or if there is aurora to be seen, but with more traffic comes higher server costs. Consider a donation if you enjoy SpaceWeatherLive so we can keep the website online!
Space weather facts
| Last X-flare | 2024/03/28 | X1.1 |
| Last M-flare | 2024/04/27 | M3.0 |
| Last geomagnetic storm | 2024/04/26 | Kp5+ (G1) |
| Spotless days | |
|---|---|
| Last spotless day | 2022/06/08 |
| Monthly mean Sunspot Number | |
|---|---|
| March 2024 | 104.9 -19.8 |
| Last 30 days | 137.7 +30.3 |