Spotless Sun, CH HSS sparks geomagnetic storms

Spotless Sun, CH HSS sparks geomagnetic storms

Geomagnetic storming reaching G1 - Minor levels is underway as our planet moves through a stream of high-speed solar wind. At the same time, solar activity is at very low levels with no flare activity and a spotless Sun on its Earth-facing side.

Over the past 24 hours, the 2 MeV electron flux was at normal levels due to electron redistribution associated with Co-rotating Interaction Region (CIR) arrival ahead of the Coronal Hole High Speed Stream (CH HSS). 

It is expected to be at normal to moderate levels on October 12 while high levels are expected on October 13 and 14 as CH HSS influence continues.

3-day satellite environment October 9 - 12, 2017Space weather overview October 9 - 12, 2017

Solar wind parameters were also indicative of CIR passage and the onset of CH HSS over the past 24 hours. Total field strength ranged primarily from 2 to 13 nT, while the Bz component varied. Solar wind speed gradually increased from about 400 km/s to near 530 km/s.

The geomagnetic field fist reached G1 - Minor storming levels due to CIR at 08:51 UTC on October 11 and again at 17:51 UTC and 00:40 UTC on October 12.

It is expected to range from unsettled to G1 - Minor storming levels on October 12 as CH HSS influences continue.

Unsettled to active conditions are expected on October 13, with periods of G1 storming likely. Primarily active levels, with a chance for isolated periods of G1 storming are expected on October 14 as CH HSS influences persist.

Estimated planetary K-index 3-day October 9 - 12, 20173-hour K-indices for last 7 days - October 12, 2017

At the same time, solar activity is at very low levels with no flare activity and a spotless Sun.

Spotless Sun and coronal holes on October 12, 2017

Spotless Sun and coronal holes on October 12, 2017.

SWPC alerts, watches and warnings

Space Weather Message Code: WARK05
Serial Number: 1417
Issue Time: 2017 Oct 12 1044 UTC

EXTENDED WARNING: Geomagnetic K-index of 5 expected
Extension to Serial Number: 1416
Valid From: 2017 Oct 11 0730 UTC
Now Valid Until: 2017 Oct 12 1800 UTC
Warning Condition: Persistence

NOAA Space Weather Scale descriptions can be found at
www.swpc.noaa.gov/noaa-scales-explanation

Potential Impacts: Area of impact primarily poleward of 60 degrees Geomagnetic Latitude.
Induced Currents - Weak power grid fluctuations can occur.
Spacecraft - Minor impact on satellite operations possible.
Aurora - Aurora may be visible at high latitudes, i.e., northern tier of the U.S. such as northern Michigan and Maine.

***

Space Weather Message Code: ALTK05
Serial Number: 1176
Issue Time: 2017 Oct 12 0041 UTC

ALERT: Geomagnetic K-index of 5
Threshold Reached: 2017 Oct 12 0040 UTC

Synoptic Period: 0000-0300 UTC

Active Warning: Yes
NOAA Scale: G1 - Minor

NOAA Space Weather Scale descriptions can be found at
www.swpc.noaa.gov/noaa-scales-explanation

Potential Impacts: Area of impact primarily poleward of 60 degrees Geomagnetic Latitude.
Induced Currents - Weak power grid fluctuations can occur.
Spacecraft - Minor impact on satellite operations possible.
Aurora - Aurora may be visible at high latitudes, i.e., northern tier of the U.S. such as northern Michigan and Maine.

***

Space Weather Message Code: WARK05
Serial Number: 1416
Issue Time: 2017 Oct 11 2357 UTC

EXTENDED WARNING: Geomagnetic K-index of 5 expected
Extension to Serial Number: 1415
Valid From: 2017 Oct 11 0730 UTC
Now Valid Until: 2017 Oct 12 1200 UTC
Warning Condition: Persistence

NOAA Space Weather Scale descriptions can be found at
www.swpc.noaa.gov/noaa-scales-explanation

Potential Impacts: Area of impact primarily poleward of 60 degrees Geomagnetic Latitude.
Induced Currents - Weak power grid fluctuations can occur.
Spacecraft - Minor impact on satellite operations possible.
Aurora - Aurora may be visible at high latitudes, i.e., northern tier of the U.S. such as northern Michigan and Maine.

***

Space Weather Message Code: ALTK05
Serial Number: 1175
Issue Time: 2017 Oct 11 1751 UTC

ALERT: Geomagnetic K-index of 5
Threshold Reached: 2017 Oct
11 1748 UTC
Synoptic Period: 1500-1800 UTC

Active Warning: Yes
NOAA Scale: G1 - Minor

NOAA Space Weather Scale descriptions can be found at
www.swpc.noaa.gov/noaa-scales-explanation

Potential Impacts: Area of impact primarily poleward of 60 degrees Geomagnetic Latitude.
Induced Currents - Weak power grid fluctuations can occur.
Spacecraft - Minor impact on satellite operations possible.
Aurora - Aurora may be visible at high latitudes, i.e., northern tier of the U.S. such as northern Michigan and Maine.

***

Space Weather Message Code: WARK05
Serial Number: 1415
Issue Time: 2017 Oct 11 1419 UTC

EXTENDED WARNING: Geomagnetic K-index of 5 expected
Extension to Serial Number: 1414
Valid From: 2017 Oct 11 0730 UTC
Now Valid Until: 2017 Oct 11 2359 UTC
Warning Condition: Persistence

NOAA Space Weather Scale descriptions can be found at
www.swpc.noaa.gov/noaa-scales-explanation

Potential Impacts: Area of impact primarily poleward of 60 degrees Geomagnetic Latitude.
Induced Currents - Weak power grid fluctuations can occur.
Spacecraft - Minor impact on satellite operations possible.
Aurora - Aurora may be visible at high latitudes, i.e., northern tier of the U.S. such as northern Michigan and Maine.

***

Space Weather Message Code: ALTK05
Serial Number: 1174
Issue Time: 2017 Oct 11 0851 UTC

ALERT: Geomagnetic K-index of 5
Threshold Reached: 2017 Oct 11 0851 UTC

Synoptic Period: 0600-0900 UTC

Active Warning: Yes
NOAA Scale: G1 - Minor

NOAA Space Weather Scale descriptions can be found at
www.swpc.noaa.gov/noaa-scales-explanation

Potential Impacts: Area of impact primarily poleward of 60 degrees Geomagnetic Latitude.
Induced Currents - Weak power grid fluctuations can occur.
Spacecraft - Minor impact on satellite operations possible.
Aurora - Aurora may be visible at high latitudes, i.e., northern tier of the U.S. such as northern Michigan and Maine.

***

Space Weather Message Code: WARK05
Serial Number: 1414
Issue Time: 2017 Oct 11 0728 UTC

WARNING: Geomagnetic K-index of 5 expected
Valid From: 2017 Oct 11 0730 UTC
Valid To: 2017 Oct 11 1500 UTC
Warning Condition: Onset
NOAA Scale: G1 - Minor

NOAA Space Weather Scale descriptions can be found at
www.swpc.noaa.gov/noaa-scales-explanation

Potential Impacts: Area of impact primarily poleward of 60 degrees Geomagnetic Latitude.
Induced Currents - Weak power grid fluctuations can occur.
Spacecraft - Minor impact on satellite operations possible.
Aurora - Aurora may be visible at high latitudes, i.e., northern tier of the U.S. such as northern Michigan and Maine.

***

Space Weather Message Code: ALTK04
Serial Number: 2009
Issue Time: 2017 Oct 11 0553 UTC

ALERT: Geomagnetic K-index of 4
Threshold Reached: 2017 Oct 11 0551 UTC
Synoptic Period: 0300-0600 UTC

Active Warning: Yes

NOAA Space Weather Scale descriptions can be found at
www.swpc.noaa.gov/noaa-scales-explanation

Potential Impacts: Area of impact primarily poleward of 65 degrees Geomagnetic Latitude.
Induced Currents - Weak power grid fluctuations can occur.
Aurora - Aurora may be visible at high latitudes such as Canada and Alaska.

***

Space Weather Message Code: WARK04
Serial Number: 3339
Issue Time: 2017 Oct 11 0151 UTC

WARNING: Geomagnetic K-index of 4 expected
Valid From: 2017 Oct 11 0150 UTC
Valid To: 2017 Oct 12 2359 UTC
Warning Condition: Onset

NOAA Space Weather Scale descriptions can be found at
www.swpc.noaa.gov/noaa-scales-explanation

Potential Impacts: Area of impact primarily poleward of 65 degrees Geomagnetic Latitude.
Induced Currents - Weak power grid fluctuations can occur.
Aurora - Aurora may be visible at high latitudes such as Canada and Alaska.

Featured image: Auroras taken by Eva Kristiansen on October 11, 2017 at Tromsø, Norway (via SpaceWeather.com)

Tags: ch hss, g1 storm

Comments

No comments yet. Why don't you post the first comment?

Post a comment

Your name: *

Your email address: *

Comment text: *

The image that appears on your comment is your Gravatar