Viewing archive of Friday, 18 July 2003

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 2003 Jul 18 2200 UTC
Prepared by the NOAA © SWPC and processed by

Joint USAF/NOAA Report of Solar and Geophysical Activity

SDF Number 199 Issued at 2200Z on 18 Jul 2003

IA. Analysis of Solar Active Regions and Activity from 17-2100Z to 18-2100Z

Solar activity was at low levels. Region 410 (S11W01) produced two consecutive C5 flares at 17/2356Z and 18/0005Z. Region 410 continues to increase in area coverage and magnetic complexity. Region 412 (N17W06) exhibited growth in area and magnetic complexity, developing a beta-gamma magnetic configuration due to mixing polarities in the trailing spots. Region 409 (N15E05) continued its gradual decay and simplified to a beta magnetic configuration. New Region 414 (S02E58) was numbered today.
IB. Solar Activity Forecast
Solar activity is expected to be low to moderate. Regions 410, and 412 have the potential for M-class activity over the next three days. Region 409 has the potential for M-class activity on day one.
IIA. Geophysical Activity Summary 17-2100Z to 18-2100Z
The geomagnetic field has been quiet to active. Active conditions were observed early in the period. Solar wind speed decreased from 600 km/s to 500 km/s around 18/0700Z and remained at 500 km/s for the remainder of the day. This decrease marks the end of the coronal hole high speed stream.
IIB. Geophysical Activity Forecast
The geomagnetic field is expected to be at quiet to unsettled levels. Isolated active conditions are possible during night time hours.
III. Event Probabilities 19 Jul to 21 Jul
Class M45%45%45%
Class X05%05%05%
IV. Penticton 10.7 cm Flux
  Observed       18 Jul 140
  Predicted   19 Jul-21 Jul  135/140/140
  90 Day Mean        18 Jul 127
V. Geomagnetic A Indices
  Observed Afr/Ap 17 Jul  014/022
  Estimated     Afr/Ap 18 Jul  012/012
  Predicted    Afr/Ap 19 Jul-21 Jul  015/015-015/015-012/012
VI. Geomagnetic Activity Probabilities 19 Jul to 21 Jul
A. Middle Latitudes
Minor storm20%20%15%
Major-severe storm05%05%01%
B. High Latitudes
Minor storm20%20%20%
Major-severe storm05%05%05%

All times in UTC

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