Viewing archive of Wednesday, 18 March 1998
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 1998 Mar 18 2200 UTCPrepared by the NOAA © SWPC and processed by SpaceWeatherLive.com
Joint USAF/NOAA Report of Solar and Geophysical Activity
SDF Number 077 Issued at 2200Z on 18 MAR 1998IA. Analysis of Solar Active Regions and Activity from 17-2100Z to 18-2100Z
SOLAR ACTIVITY WAS MODERATE BY VIRTUE OF A SINGLE,
UNCORRELATED M1 X-RAY BURST AT 18/1112Z. REGION 8179 (S21W44), NOW
AN EKC SPOT GROUP COVERING 790 MILLIONTHS OF WHITE LIGHT AREA IN A
BETA-GAMMA MAGNETIC CONFIGURATION, WAS RESPONSIBLE FOR TWO C-CLASS
FLARES, A C1.9/SF AT 18/0046Z AND A C1.2/SF AT 18/0300Z. THE
REMAINDER OF THE SPOTTED REGIONS AND THE SOLAR LIMB WERE QUIET AND
RELATIVELY STABLE. NEW REGIONS 8182 (S22W58), A BXO SPOT GROUP, AND
8183 (N22W58), A GROWING CRO SPOT GROUP, WERE NUMBERED TODAY.
IB. Solar Activity Forecast
SOLAR ACTIVITY IS EXPECTED TO REMAIN
LOW TO MODERATE OVER THE COURSE OF THE FORECAST PERIOD. REGION 8179
HAS AN EXCELLENT CHANCE OF CONTINUED C-CLASS ACTIVITY, A GOOD CHANCE
OF ISOLATED M-CLASS FLARES, AND A SMALL CHANCE OF AN ISOLATED
X-CLASS EVENT AS THIS REGION BEGINS TO STRESS ITS MAGNETIC GRADIENT.
IIA. Geophysical Activity Summary 17-2100Z to 18-2100Z
THE GEOMAGNETIC FIELD HAS BEEN MOSTLY QUIET AT ALL LATITUDES. THE
GREATER THAN 2 MEV ENERGETIC ELECTRON FLUX EXCEEDED THE ALERT
THRESHOLD AGAIN TODAY.
IIB. Geophysical Activity Forecast
THE GEOMAGNETIC FIELD IS
EXPECTED TO BE QUIET TO UNSETTLED FOR THE NEXT 36 HOURS, THEN MOSTLY
QUIET. HIGH LATITUDE STATIONS MAY SEE ISOLATED PERIODS OF UNSETTLED
TO ACTIVE LEVELS OVER THE NEXT 48 HOURS IN RESPONSE TO THE WEAK
M1/1B PARTIAL HALO/CME OBSERVED ON 15/1900Z.
III. Event Probabilities 19 MAR to 21 MAR
| Class M | 40% | 40% | 35% |
| Class X | 10% | 10% | 05% |
| Proton | 05% | 05% | 05% |
| PCAF | GREEN | ||
IV. Penticton 10.7 cm Flux
Observed 18 MAR 127 Predicted 19 MAR-21 MAR 128/130/128 90 Day Mean 18 MAR 097
V. Geomagnetic A Indices
OBSERVED AFR/AP 17 MAR 006/007 ESTIMATED AFR/AP 18 MAR 005/005 PREDICTED AFR/AP 19 MAR-21 MAR 010/010-005/008-005/008
VI. Geomagnetic Activity Probabilities 19 MAR to 21 MAR
| A. Middle Latitudes | |||
|---|---|---|---|
| Active | 20% | 10% | 10% |
| Minor storm | 05% | 05% | 05% |
| Major-severe storm | 05% | 05% | 05% |
| B. High Latitudes | |||
|---|---|---|---|
| Active | 20% | 15% | 10% |
| Minor storm | 10% | 10% | 05% |
| Major-severe storm | 05% | 05% | 05% |
All times in UTC
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