Viewing archive of Wednesday, 17 March 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 Mar 17 2200 UTCPrepared by the NOAA © SWPC and processed by SpaceWeatherLive.com
Joint USAF/NOAA Report of Solar and Geophysical Activity
SDF Number 076 Issued at 2200Z on 17 MAR 1999IA. Analysis of Solar Active Regions and Activity from 16-2100Z to 17-2100Z SOLAR ACTIVITY WAS HIGH. REGION 8485 (N24W52) CONTINUES
TO PRODUCE M-CLASS X-RAY FLARES. THE LARGEST EVENT WAS AN M6/2N AT
16/2144Z. TWO OTHER M-CLASS FLARES WERE OBSERVED - AN M3/1F AT
17/0956Z, AND AN M1/SN AT 17/1449Z. THIS ACTIVE F-TYPE GROUP
EXHIBITED NO SIGNIFICANT CHANGE IN THE PAST 24 HOURS AS IT
APPROACHES THE WEST LIMB. ERUPTIVE PROMINENCES WERE OBSERVED IN
PROGRESS ON THE NW LIMB AT 17/0119Z AND NE LIMB AT 17/0717Z. CORONAL
MASS EJECTIONS OCCURRED WITH BOTH ERUPTIONS. NEW REGION 8490
(S20E66) WAS NUMBERED TODAY. REMAINING REGIONS WERE QUIET.
IB. Solar Activity Forecast
SOLAR ACTIVITY IS EXPECTED TO BE
MODERATE. REGION 8485 IS EXPECTED TO CONTINUE PRODUCING ISOLATED
M-CLASS FLARES
IIA. Geophysical Activity Summary 16-2100Z to 17-2100Z
THE GEOMAGNETIC FIELD WAS MOSTLY QUIET WITH AN ISOLATED UNSETTLED
PERIOD BETWEEN 17/1500 - 17/1800Z.
IIB. Geophysical Activity Forecast
THE GEOMAGNETIC FIELD IS
EXPECTED TO BE QUIET TO UNSETTLED WITH ISOLATED ACTIVE CONDITIONS.
III. Event Probabilities 18 MAR to 20 MAR
| Class M | 50% | 45% | 25% |
| Class X | 10% | 05% | 05% |
| Proton | 05% | 05% | 05% |
| PCAF | GREEN | ||
IV. Penticton 10.7 cm Flux
Observed 17 MAR 155 Predicted 18 MAR-20 MAR 150/145/135 90 Day Mean 17 MAR 142
V. Geomagnetic A Indices
OBSERVED AFR/AP 16 MAR 003/004 ESTIMATED AFR/AP 17 MAR 005/010 PREDICTED AFR/AP 18 MAR-20 MAR 012/012-012/010-005/008
VI. Geomagnetic Activity Probabilities 18 MAR to 20 MAR
| A. Middle Latitudes | |||
|---|---|---|---|
| Active | 30% | 30% | 20% |
| Minor storm | 05% | 05% | 05% |
| Major-severe storm | 01% | 01% | 01% |
| B. High Latitudes | |||
|---|---|---|---|
| Active | 35% | 35% | 25% |
| Minor storm | 10% | 10% | 05% |
| Major-severe storm | 01% | 01% | 01% |
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