Geomagnetic activity at normal levels while another CME impact expected

NOAA/SWPC reported that the G1 (minor) Geomagnetic Storm has ended with the return of normal solar wind conditions. Currently solar winds blow at speed of 419.1 km/sec. Earthbound proton levels are now below the S1 Minor Radiation Storm threshold and geomagnetic field is back to normal levels. Last 24 hours we experienced G2 (moderate) geomagnetic storm  levels, with planetary K index reaching Kp=6 level, S1 (minor) solar radiation storm, ground currents and high latitude bright auroras. All the events were induced by arrival of CME cloud generated by large solar filament observed on August 31.

Fast-growing Sunspot AR1564 has developed a ‘beta-gamma’ magnetic field and it could produce M-class solar flares. More C-class flares are expected, especially from active regions 1564 (Catania 67) and 1560 (Catania 64). NOAA/SWPC estimated 30 % chances of M-class solar flares and 5 % chances of X-class events in the next 24 hours. Earth is still expecting arrival of the CME’s from September 2. Unsettled (K=3) to active (K=5) conditions are possible tomorrow.

A large solar prominence generated Coronal Mass Ejection (CME) on the Sun this morning. CME is clearly seen in the latest Lasco C2 images. It is not Earth-directed.

 

Joint USAF/NOAA Report of Solar and Geophysical Activity ( 22:00 UTC, September 4, 2012)

Solar activity was low. Region 1564 (S14E14 – Esi/beta-gamma) was the most active region, producing occasional low-level C-class flares. It increased in spot count and area during the first half of the period, but showed gradual spot and penumbral decay during the latter half of the period. Region 1560 (N04W47 – Eai/beta-gamma-delta) showed a slight decrease in spots and area, but maintained a delta in its interior spots. No significant changes were observed in the remaining spotted regions and no new regions were numbered. No Earth-directed CME activity was observed during the period.

Solar activity is expected to be low through the period (05 – 07 September) with a chance for an isolated M-class flare.

Geomagnetic field activity ranged from quiet to minor storm levels with major storm periods detected at high latitudes, all due to residual CME effects. The greater than 10 MeV proton event at geosynchronous orbit that began at 01/1335Z, reached a maximum of 59 pfu at 02/0850Z, and ended at 04/0625Z.

Geomagnetic field activity is expected to be at quiet to unsettled levels during days 1 – 2 (05 – 06 September) with a chance for active levels. This is due to the arrival of CMEs observed on 02 September along with a co-rotating
interaction region in advance of a coronal hole high-speed stream (CH HSS). The CMEs are expected to arrive around midday on day 1. The CH HSS is expected to commence on day 2. Field activity is expected to be at quiet to unsettled levels on day 3 (07 September) as CH HSS effects subside.

CURRENT CONDITIONS

Solar wind
speed: 473.6 km/sec
density: 2.6 protons/cm³

The Radio Sun
10.7 cm flux: 142 sfu

Planetary K-index
Now: Kp= 2 quiet
24-hr max: Kp= 4 unsettled

Interplanetary Mag. Field
B_total: 12.1 nT
B_z: 6.8 nT south