Viewing archive of Tuesday, 11 December 2001

Solar activity report

Report of Solar-Geophysical Activity 2001 Dec 11 2200 UTC
Prepared by the NOAA © SWPC and processed by

Joint USAF/NOAA Report of Solar and Geophysical Activity

SDF Number 345 Issued at 2200Z on 11 Dec 2001

IA. Analysis of Solar Active Regions and Activity from 10-2100Z to 11-2100Z

Solar activity increased to high levels. Region 9733 (N15E32) produced an impulsive X2/Sf flare at 11/0808 UTC. The flare was associated with Type II and IV radio sweeps, a 2600 sfu Tenflare, and a coronal mass ejection (CME) that did not appear to be Earth-directed. Region 9733 showed increased area and magnetic complexity with at least one magnetic delta configuration within its northern-most trailer spots. Region 9727 (S22W36) produced an impulsive M1/2n flare at 11/1451 UTC associated with relatively minor radio emission. This region showed minor growth in spot number and area with two delta magnetic configurations evident within its large trailing spot mass.
IB. Solar Activity Forecast
Solar activity is expected to be at moderate to high levels. Isolated M-class flares are expected from Regions 9727 and 9733. Either region could produce a major flare during the period as well.
IIA. Geophysical Activity Summary 10-2100Z to 11-2100Z
Geomagnetic field activity was at quiet levels.
IIB. Geophysical Activity Forecast
Geomagnetic field activity is expected to be at quiet to unsettled levels through the period. There will be a chance for a proton flare from Regions 9727 and 9733.
III. Event Probabilities 12 Dec to 14 Dec
Class M80%80%80%
Class X20%20%20%
IV. Penticton 10.7 cm Flux
  Observed       11 Dec 221
  Predicted   12 Dec-14 Dec  215/210/210
  90 Day Mean        11 Dec 218
V. Geomagnetic A Indices
  Observed Afr/Ap 10 Dec  003/004
  Estimated     Afr/Ap 11 Dec  005/005
  Predicted    Afr/Ap 12 Dec-14 Dec  007/008-012/010-012/015
VI. Geomagnetic Activity Probabilities 12 Dec to 14 Dec
A. Middle Latitudes
Minor storm05%10%10%
Major-severe storm01%01%01%
B. High Latitudes
Minor storm05%15%15%
Major-severe storm01%01%01%

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