Viewing archive of Saturday, 21 September 2013

Daily bulletin on solar and geomagnetic activity from the SIDC

Issued: 2013 Sep 21 1358 UTC

SIDC Forecast

Valid from 1230 UTC, 21 Sep 2013 until 23 Sep 2013
Solar flares

Eruptive (C-class flares expected, probability >=50%)

Geomagnetism

Active conditions expected (A>=20 or K=4)

Solar protons

Quiet

10cm fluxAp
21 Sep 2013108008
22 Sep 2013110015
23 Sep 2013115011

Bulletin

Solar activity is still low with the flaring at the C-class level. The strongest flare reported was C3.8 flare, peaking at 12:03 UT on September 20. All the C-class flares, in last 48 hours originated from the same NOAA AR 1850 which still has potential to produce C-class, and possibly M-class flares. Earth is inside the slow solar wind with the speed of about 410 km/s.The interplanetary magnetic field magnitude is stable having value of about 5 nT. The geomagnetic conditions are at the moment quiet. We expect quiet to active geomagnetic conditions in the following 48 hours due to the arrival of a fast flow (in the morning of September 22), associated with the low-latitude coronal hole in the northern hemisphere. The CME associated with the prominence eruption from September 19 is expected to arrive at the Earth on September 23.

Today's estimated international sunspot number (ISN): 053, based on 08 stations.

Solar indices for 20 Sep 2013

Wolf number Catania///
10cm solar flux109
AK Chambon La Forêt013
AK Wingst010
Estimated Ap008
Estimated international sunspot number061 - Based on 19 stations

Noticeable events summary

DayBeginMaxEndLocStrengthOP10cmCatania/NOAARadio burst types
None

Provided by the Solar Influences Data analysis Center© - SIDC - Processed by SpaceWeatherLive

All times in UTC

<< Go to daily overview page

Latest news

Support SpaceWeatherLive.com!

A lot of people come to SpaceWeatherLive to follow the Solar activity or if there is a chance to see the aurora, but with more traffic comes higher costs to keep the servers online. If you like SpaceWeatherLive and want to support the project you can choose a subscription for an ad-free site or consider a donation. With your help we can keep SpaceWeatherLive online!

No Ads on SWL Pro!
No Ads on SWL Pro! Subscriptions
Donations
Support SpaceWeatherLive.com! Donate
Support SpaceWeatherLive with our merchandise
Check out our merchandise

Latest alerts

Get instant alerts!

Space weather facts

Last X-flare2025/12/08X1.1
Last M-flare2025/12/09M1.5
Last geomagnetic storm2025/12/04Kp5 (G1)
Spotless days
Last spotless day2022/06/08
Monthly mean Sunspot Number
November 202591.8 -22.8
December 2025160.6 +68.8
Last 30 days108.7 +12.8

This day in history*

Solar flares
12025M2.0
22025M1.67
32025M1.5
42023M1.5
52025M1.33
DstG
11993-62
21974-58G1
32003-53G1
41982-49G1
51976-48
*since 1994

Social networks