SFI = 122
A index = 22
K index = 3
SSN = 124
GEOMAGNETIC STORM WARNING: Geomagnetic storms are possible on July 23rd when a full-halo CME is expected to hit Earth’s magnetic field. The storm cloud was hurled toward Earth yesterday by a solar tsunami eruption. NOAA forecasters say that G1– to G2-class (minor to moderate) storms are likely with a slight chance of escalating to category G3 (strong).
Exactly what time will the CME hit? This NASA model of the approaching cloud pinpoints the impact within a few hours around 0000 UT on July 23rd:
In the animation, Earth is marked by a yellow dot. Note that Mars, a red dot, also gets hit–a glancing blow on July 25th.
An independent NOAA model of the CME predicts a slightly later arrival, with the densest part of the storm cloud reaching Earth around 0400 UT on July 23rd. Either way, NOAA or NASA, the timing favors sky watchers in western Europe and North America. In the most optimistic case of a G3-category storm, auroras could descend as far south as Illinois and Oregon (geomagnetic latitude 50 degrees) during the night of July 22-23.
NOAA STI
:Product: Geophysical Alert Message wwv.txt
:Issued: 2022 Jul 22 0605 UTC
# Prepared by the US Dept. of Commerce, NOAA, Space Weather Prediction Center
#
# Geophysical Alert Message
#
Solar-terrestrial indices for 21 July follow.
Solar flux 122 and estimated planetary A-index 22.
The estimated planetary K-index at 0600 UTC on 22 July was 3.
Space weather for the past 24 hours has been minor.
Geomagnetic storms reaching the G1 level occurred.
Space weather for the next 24 hours is predicted to be moderate.
Geomagnetic storms reaching the G2 level are likely.
NOAA Alerts
Space Weather Message Code: WARK04
Serial Number: 4144
Issue Time: 2022 Jul 22 0506 UTC
EXTENDED WARNING: Geomagnetic K-index of 4 expected
Extension to Serial Number: 4143
Valid From: 2022 Jul 21 1107 UTC
Now Valid Until: 2022 Jul 22 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 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.