Past Events
Since our last forecast the solar activity was at low levels. Even though the new active regions and sunspots emerged from time to time, overall activity remained low. There were no M and X level solar flares. CMEs with speeds less than 250 km/s were observed, however none of them were Earth-directed. The arrival of the CME observed from LASCO C2 on April 14 caused an interplanetary shock on April 20. Consequently, a slight increase in geomagnetic conditions was observed. Maximum Kp was 5. There were high speed streams occasionally and two of them caused radiation belt enhancements on March 23 and April 1. After 20 days which the solar disk remained as spottless, sunspots has been observed on April 26 and merged to AR2760 eventually.
Within the last 24 hours the solar activity remained at low levels. The AR2760 did not produce any solar flares. There is a large coronal whole at the South pole and two other smaller near the center. The solar wind speed varied between 370 and 450 km/s. The strength of southward component of IMF was 6.1 nT at its maximum. The magnetopause standoff distance was 9 Re at its minimum. The geomagnetic indice Dst was -32 at its minimum and AE was between 500 and 1000 nT. The maximum Kp level was 3. The F10.7 radio flux was 69 sfu which is normal during solar minimum.
Solar activity is expected to be remain at low levels in the following days. No CME arrivals are expected since none observed through coronagraph imagery. The solar wind speed is expected to remain at slightly elevated levels (around 400 km/s or greater) due to the coronal holes. One of the coronal holes at around the solar disk passed the central meridian, yet the other one is right at the center. Thus the effects of those two coronal holes might be observed. ASSA flare model predicts the occurence possibility of C, M and X class flares as, 30%, 5% and 0% respectively.
Forecaster: Ezgi Gülay
MSc. Student
Faculty of Aeronautics and Astronautics, ITU
Supervisor: Dr. Emine Ceren Kalafatoğlu Eyigüler