Viewing archive of Monday, 17 May 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 May 17 2200 UTC
Prepared by the NOAA © SWPC and processed by SpaceWeatherLive.com

Joint USAF/NOAA Report of Solar and Geophysical Activity

SDF Number 137 Issued at 2200Z on 17 MAY 1999

IA. Analysis of Solar Active Regions and Activity from 16-2100Z to 17-2100Z

SOLAR ACTIVITY WAS MODERATE. THE MOST SIGNIFICANT EVENTS WERE AN UNCORRELATED M2.3 X-RAY FLARE AT 17/0449Z AND AN M1 X-RAY FLARE AT 16/2225Z CORRELATED TO OPTICAL ACTIVITY IN REGION 8541 (N22W37). REGION 8548 (S21E48) WAS NUMBERED TODAY.
IB. Solar Activity Forecast
SOLAR ACTIVITY IS EXPECTED TO BE LOW TO MODERATE.
IIA. Geophysical Activity Summary 16-2100Z to 17-2100Z
THE GEOMAGNETIC FIELD HAS BEEN QUIET.
IIB. Geophysical Activity Forecast
THE GEOMAGNETIC FIELD IS EXPECTED TO BE QUIET.
III. Event Probabilities 18 MAY to 20 MAY
Class M30%25%20%
Class X05%01%01%
Proton05%01%01%
PCAFGREEN
IV. Penticton 10.7 cm Flux
  Observed       17 MAY 145
  Predicted   18 MAY-20 MAY  145/140/140
  90 Day Mean        17 MAY 129
V. Geomagnetic A Indices
OBSERVED AFR/AP 16 MAY  003/006
ESTIMATED AFR/AP 17 MAY  003/008
PREDICTED AFR/AP 18 MAY-20 MAY  005/010-005/010-008/008
VI. Geomagnetic Activity Probabilities 18 MAY to 20 MAY
A. Middle Latitudes
Active10%10%15%
Minor storm05%05%05%
Major-severe storm01%01%01%
B. High Latitudes
Active15%15%15%
Minor storm05%05%05%
Major-severe storm01%01%01%

All times in UTC

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