Viewing archive of Thursday, 17 August 2017

Daily bulletin on solar and geomagnetic activity from the SIDC

Issued: 2017 Aug 17 1230 UTC

SIDC Forecast

Valid from 1230 UTC, 17 Aug 2017 until 19 Aug 2017
Solar flares

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

Geomagnetism

Minor storm expected (A>=30 or K=5)

Solar protons

Quiet

10cm fluxAp
17 Aug 2017077032
18 Aug 2017080021
19 Aug 2017082007

Bulletin

NOAA AR 2671 continued to grow and has evolved into a beta-gamma- delta magnetic field configuration. Nevertheless, it has not produced any flare above the B-class level in past 24 h. The situation can change as this region will likely generate C-class flares, and has potential for M- (and even X-) class flares. It produced a CME directed to the west first seen at 14:00 UT (LASCO-C2) on August 16, that will most likely miss the Earth.

No Earth directed Coronal Mass Ejections (CMEs) have been detected. Solar protons have remained at background levels over the past 24 hours.

Geomagnetic conditions have been disturbed due to the expected arrival of a high speed stream from a coronal hole (Kp reached 5 at 06:00 UT and the local K went up to 4 at 09:00 UT). Solar wind speed is increasing and currently around 550 km/s with interplanetary magnetic field intensity of 11 nT, with periods of negative Bz since early today. More disturbed conditions are expected in the next 48 h with K up to 6.

Today's estimated international sunspot number (ISN): 040, based on 19 stations.

Solar indices for 16 Aug 2017

Wolf number Catania///
10cm solar flux077
AK Chambon La Forêt014
AK Wingst008
Estimated Ap008
Estimated international sunspot number030 - Based on 30 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-flare2025/06/19X1.9
Last M-flare2025/10/03M1.2
Last geomagnetic storm2025/10/03Kp5 (G1)
Spotless days
Last spotless day2022/06/08
Monthly mean Sunspot Number
September 2025129.8 -3.7
October 2025140.1 +10.3
Last 30 days131.3 -1.2

This day in history*

Solar flares
12012M3.35
22024M1.2
31999C9.19
42024C8.0
52023C6.6
DstG
12024-153G3
21960-112G1
32002-108G2
42012-99G2
52015-97G2
*since 1994

Social networks