Viewing archive of Wednesday, 25 September 2019

Daily bulletin on solar and geomagnetic activity from the SIDC

Issued: 2019 Sep 25 1230 UTC

SIDC Forecast

Valid from 1230 UTC, 25 Sep 2019 until 27 Sep 2019
Solar flares

Quiet conditions (<50% probability of C-class flares)

Geomagnetism

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

Solar protons

Quiet

10cm fluxAp
25 Sep 2019067009
26 Sep 2019067007
27 Sep 2019066017

Bulletin

Solar X-ray flux remained below B class levels throughout the period. The Solar disk is spotless and the X-ray flux is expected to remain at or below background levels.

There were no Earth-directed Coronal Mass Ejections (CME) observed in coronagraph data.

Proton levels were at background values and are expected to remain so.

The solar wind speed has fluctuated between 350 and 500 km/s over the past 24 hours. The total magnetic field strength has fluctuated between 2 and 17 nT peaking at 17:00 UT yesterday. The Bz between -9 and 15 nT. Geomagnetic conditions ranged between Kp index 1-4 (NOAA) and local K index 0-3 (Dourbes).

The solar wind conditions became enhanced late yesterday and early this morning due to the arrival of a high speed stream (HSS) from a recurrent equatorial coronal hole. Solar wind conditions are expected to be enhanced throughout the day, before abating later today / early tomorrow. As a consequence geomagnetic conditions are expected to be unsettled, with some active periods due to HSS solar wind enhancements.

Around 27-Sep-2019 we may begin to feel the effects from a second larger recurrent coronal hole, which has just passed the central meridian. On the coronal holes last rotation the resultant HSS produced Kp 6 (NOAA).

Today's estimated international sunspot number (ISN): 000, based on 13 stations.

Solar indices for 24 Sep 2019

Wolf number Catania///
10cm solar flux067
AK Chambon La Forêt015
AK Wingst014
Estimated Ap013
Estimated international sunspot number000 - Based on 18 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 Sun's activity or if there is aurora to be seen, but with more traffic comes higher server costs. Consider a donation if you enjoy SpaceWeatherLive so we can keep the website online!

Donate SpaceWeatherLive Pro
Support SpaceWeatherLive with our merchandise
Check out our merchandise

Latest alerts

Get instant alerts!

Space weather facts

Last X-flare2025/03/28X1.1
Last M-flare2025/04/01M2.5
Last geomagnetic storm2025/03/27Kp5 (G1)
Spotless days
Last spotless day2022/06/08
Monthly mean Sunspot Number
February 2025154.6 +17.6
April 2025152.5 -2.1
Last 30 days130.7 -17.9

This day in history*

Solar flares
12001X1.77
22017M8.35
31999M6.2
42001M3.57
52017M1.81
DstG
11979-168G4
21960-151G3
31992-105G2
42004-104G2
51994-103G3
*since 1994

Social networks