***********************************************************************
Product: Daily Forecast of Geomagnetic Activity
Issued: 2026 September 13 07:36UTC
Prepared by the Athens Space Weather Forecasting Center
***********************************************************************

I. Solar activity
--Current Status
Solar Flux (10.7cm) measured on 12.09.2026 at 23:00 UTC was 109 sfu.
The background X-Ray flux is at the class B3.09 level.
No obviously Earth directed CMEs were observed in available LASCO imagery on September 09-11.
A coronal hole (CH1398) at southern hemisphere will be Earth facing on September 10-14.
A coronal hole (CH1399) at northern hemisphere will rotate across the central meridian on September 12-14.

II. Solar Energetic Particle Events
Protons and electrons fluxes are quiet.

III. Interplanetary and Geomagnetic conditions
The solar wind speed measured by ACE satellite reached the max value 469 Km/s on September 13 at 05:38 UT during the last 24 hours.
The solar wind speed from STEREO A was detected 400 Km/s during the last 24 hours.
The vertical component of IMF Bz reached the max value -5.86 nT on September 13 at 04:20 UT during the last 24 hours.
The geomagnetic field was at quiet to unsettled levels during the last 24 hours.
The Kp index now is at unsettled levels with Kp=3.

IV. 3-day Geomagnetic Activity Forecast
The geomagnetic field is expected to be at quiet to unsettled levels on September 13 and at quiet to active levels on September 14-15.

DateAp index forecastGeomagnetic Activity level
13.09.202610Quiet to Unsettled
14.09.202618Quiet to Active
15.09.202616Quiet to Active

***************************************************************************
Athens Space Weather Forecasting Center
Physics Department, National & Kapodistrian University of Athens
Athens Neutron Monitor Station A.NE.MO.S
Tel.: +30 210 727 6901
email: spaceweather@phys.uoa.gr
URL: http://spaceweather.phys.uoa.gr
***************************************************************************