Viewing archive of Saturday, 20 February 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 Feb 20 2200 UTCPrepared by the NOAA © SWPC and processed by SpaceWeatherLive.com
Joint USAF/NOAA Report of Solar and Geophysical Activity
SDF Number 051 Issued at 2200Z on 20 FEB 1999IA. Analysis of Solar Active Regions and Activity from 19-2100Z to 20-2100Z SOLAR ACTIVITY WAS LOW. REGION 8458 (S22W74) PRODUCED A
C8/SF WITH TYPES II AND IV SWEEP AT 0406Z. THIS EVENT IMMEDIATELY
FOLLOWED ANOTHER C8 AT 0310Z THAT WAS NOT OBSERVED FROM THE GROUND.
OF THE OTHER C-CLASS EVENTS OCCURRING, THE C4/SF AT 1519Z, ALSO FROM
8458, HAD A TYPE II SWEEP. NEW REGION 8468 (N35W66) EMERGED AT A
HIGH LATITUDE. THE OTHER SIX SPOT GROUPS WERE STABLE.
IB. Solar Activity Forecast
SOLAR ACTIVITY IS EXPECTED TO PERSIST
AT LOW LEVELS.
IIA. Geophysical Activity Summary 19-2100Z to 20-2100Z
THE GEOMAGNETIC FIELD WAS QUIET TO UNSETTLED.
IIB. Geophysical Activity Forecast
THE GEOMAGNETIC FIELD IS
EXPECTED TO VARY FROM QUIET TO ACTIVE LEVELS OVER THE NEXT 3 DAYS. A
HIGH-SPEED STREAM FROM A WELL-POSITIONED CORONAL HOLE MAY AFFECT
THE NEAR-EARTH ENVIRONS IN THE NEXT 48-72 HOURS.
III. Event Probabilities 21 FEB to 23 FEB
| Class M | 20% | 20% | 20% |
| Class X | 01% | 01% | 01% |
| Proton | 01% | 01% | 01% |
| PCAF | GREEN | ||
IV. Penticton 10.7 cm Flux
Observed 20 FEB 157 Predicted 21 FEB-23 FEB 150/145/140 90 Day Mean 20 FEB 147
V. Geomagnetic A Indices
OBSERVED AFR/AP 19 FEB 024/038 ESTIMATED AFR/AP 20 FEB 003/010 PREDICTED AFR/AP 21 FEB-23 FEB 005/010-005/017-015/012
VI. Geomagnetic Activity Probabilities 21 FEB to 23 FEB
| A. Middle Latitudes | |||
|---|---|---|---|
| Active | 10% | 15% | 30% |
| Minor storm | 05% | 05% | 10% |
| Major-severe storm | 01% | 01% | 01% |
| B. High Latitudes | |||
|---|---|---|---|
| Active | 10% | 20% | 40% |
| Minor storm | 05% | 05% | 15% |
| Major-severe storm | 01% | 01% | 01% |
All times in UTC
Latest news
Friday, 1 November 2024
X2.0 solar flare
Wednesday, 9 October 2024
X1.8 solar flare, severe geomagnetic storm watch
Tuesday, 8 October 2024
Double X-flares, glancing blow possible
Latest forum messages
AR13883 2024/11/04 CME 13Unspecified geomagnetic activity 1556Coronal holes 32AR 13883 99The 2024 Aurora Summit prize winner is... 2
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 | 2024/10/31 | X2.03 |
| Last M-flare | 2024/11/05 | M2.6 |
| Last geomagnetic storm | 2024/10/12 | Kp5 (G1) |
| Spotless days | |
|---|---|
| Last spotless day | 2022/06/08 |
| Monthly mean Sunspot Number | |
|---|---|
| September 2024 | 141.4 -74.1 |
| November 2024 | 215.8 +74.4 |
| Last 30 days | 161.1 +7.2 |