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Space Weather


Warnings and Alerts
Issue Time: 2025 Dec 07 0443 UTC

WATCH: Geomagnetic Storm Category G3 Predicted

Highest Storm Level Predicted by Day:
Dec 08: G1 (Minor) Dec 09: G3 (Strong) Dec 10: G1 (Minor)

THIS SUPERSEDES ANY/ALL PRIOR WATCHES IN EFFECT

Comment: Watches for G3 (Strong) on 09 Dec and G1 (Minor) on 10 Dec are in anticipation of CME arrival from the M8 flare at 06/2039 UTC.

Potential Impacts: Area of impact primarily poleward of 50 degrees Geomagnetic Latitude.
Induced Currents - Power system voltage irregularities possible, false alarms may be triggered on some protection devices.
Spacecraft - Systems may experience surface charging; increased drag on low Earth-orbit satellites and orientation problems may occur.
Navigation - Intermittent satellite navigation (GPS) problems, including loss-of-lock and increased range error may occur.
Radio - HF (high frequency) radio may be intermittent.
Aurora - Aurora may be seen as low as Pennsylvania to Iowa to Oregon.
Space Weather Scales
Current Condition and Alerts
Issued: 2025 Dec 07 1205 UTC
Prepared by the US Dept. of Commerce, NOAA, Space Weather Prediction Center

Geophysical Alert Message

Solar-terrestrial indices for 06 December follow.
Solar flux 200 and estimated planetary A-index 16.
The estimated planetary K-index at 1200 UTC on 07 December was 2.00.

Space weather for the past 24 hours has been moderate.
Radio blackouts reaching the R2 level occurred.

Space weather for the next 24 hours is predicted to be moderate.
Geomagnetic storms reaching the G1 level are likely.
Radio blackouts reaching the R2 level are likely.
Space Weather Scales
Forecast Discussion
Issued: 2025 Dec 07 1230 UTC
Prepared by the U.S. Dept. of Commerce, NOAA, Space Weather Prediction Center

Solar Activity

.24 hr Summary...
Solar activity reached high levels when Region 4299 (N21W06,
Dao/beta-delta) produced an M1.1 (R1/Minor) flare at 06/1921 UTC.
Shortly after, the region produced an M8.1/2b (R3-strong) flare at
06/2039 UTC. Associated with the M8.1 flare was a 1,100 sfu Tenflare, a
1,143 km/s Type II sweep and a Type IV sweep. Some development was
observed around the leader spot of Region 4299, while slight decay was
noted among the trailer spots. Region 4296 (S14W11, Eki/beta) and 4294
(S15W30, Fkc/beta-gamma-delta) remained the largest of the visible disk
but only produced C-class activity in the past 24 hours. Only minor
changes were observed among the other numbered active regions.

CME activity was observed from both M-class flares. A slow,
Earth-directed CME was observed from the M1.1 and a faster, full-halo,
Earth-directed CME was observed from the M8.1 flare. The full-halo CME
is expected to overtake the initial eruption was an anticipated arrival
time at Earth early to midday on 09 Dec.

.Forecast...
M-class flares (R1-R2/Minor-Moderate) are likely over 07-09 Dec, with a
slight chance for X-class flares (R3/Strong), given past flare history
and the potential of current active regions on the disk.

Energetic Particle

.24 hr Summary...
The greater than 2 MeV electron flux in geosynchronous orbit reached
high levels with a peak flux of 2,140 pfu observed at 06/1820 UTC. The
greater than 10 MeV proton flux in geosynchronous orbit was at slightly
enhanced levels.

.Forecast...
The greater than 2 MeV electron flux is expected to continue to reach
high levels over 07-09 Dec due to elevated solar wind speeds associated
with the ongoing CH HSS.

A slight chance exists for a greater than 10 MeV proton flux enhancement
above 10 pfu (S1/Minor) through 09 Dec due to the eruptive potential of
multiple active regions across the visible disk.

Solar Wind

.24 hr Summary...
Solar wind parameters reflected the ongoing influence of a negative
polarity CH HSS. Total magnetic field strength was between 4-6 nT. The
Bz component briefly reached as far south as -5 nT. Solar wind speeds
gradually declined from initial values of about 700 km/s to
end-of-period values of about 550 km/s. Phi angle was predominantly
oriented in the negative solar sector.

.Forecast...
The solar wind environment is expected to remain enhanced by the
negative polarity coronal hole HSS over 07 Dec. An additional
enhancement is likely late on 07 Dec and in to 08 Dec due to glancing
effects from a CME that left the Sun on 04 Dec. Further enhancements are
likely early to midday on 09 Dec due to effects from the CME that left
the Sun on 06 Dec.

Geospace

.24 hr Summary...
Geomagnetic activity was at quiet to active levels due to negative
polarity coronal hole influences.

.Forecast...
The geomagnetic field is likely to reach G1 (Minor) geomagnetic storm
levels on 07-08 Dec due to the anticipated onset of influence from the
periphery of a CME that left the Sun on 04 Dec. G3 (Strong) geomagnetic
storm levels are likely early to midday on 09 Dec due to the anticipated
arrival of the CME that left the Sun on 06 Dec.
Space Weather Scales
Three Day Forecast
Issued: 2025 Dec 07 1230 UTC
Prepared by the U.S. Dept. of Commerce, NOAA, Space Weather Prediction Center

A. NOAA Geomagnetic Activity Observation and Forecast

The greatest observed 3 hr Kp over the past 24 hours was 4 (below NOAA
Scale levels).
The greatest expected 3 hr Kp for Dec 07-Dec 09 2025 is 6.67 (NOAA Scale
G3).

NOAA Kp index breakdown Dec 07-Dec 09 2025

Dec 07 Dec 08 Dec 09
00-03UT 2.67 3.00 1.67
03-06UT 3.67 5.00 (G1) 1.67
06-09UT 3.00 3.00 4.00
09-12UT 2.00 3.00 6.67 (G3)
12-15UT 2.33 3.67 6.67 (G3)
15-18UT 3.67 2.67 5.67 (G2)
18-21UT 5.00 (G1) 2.00 5.67 (G2)
21-00UT 4.00 2.00 5.33 (G1)

Rationale: Isolated periods of G1 (Minor) geomagnetic storming are
likely on 07-08 Dec due to the anticipated glancing arrival of a CME
from 04 Dec. Periods of G1 (Minor), G2 (Moderate) and G3 (Strong)
geomagnetic storming are likely on 09 Dec due to the anticipated arrival
of a CME from 06 Dec.

B. NOAA Solar Radiation Activity Observation and Forecast

Solar radiation, as observed by NOAA GOES-18 over the past 24 hours, was
below S-scale storm level thresholds.

Solar Radiation Storm Forecast for Dec 07-Dec 09 2025

Dec 07 Dec 08 Dec 09
S1 or greater 10% 10% 10%

Rationale: There is a slight chance for S1 (Minor) solar radiation storm
conditions on 07-09 Dec.

C. NOAA Radio Blackout Activity and Forecast

Radio blackouts reaching the R2 levels were observed over the past 24
hours. The largest was at Dec 06 2025 2039 UTC.

Radio Blackout Forecast for Dec 07-Dec 09 2025

Dec 07 Dec 08 Dec 09
R1-R2 65% 65% 65%
R3 or greater 15% 15% 15%

Rationale: R1-R2 (Minor-Moderate) radio blackouts are likely, with a
slight chance for R3 (Strong) or greater events, on 07-09 Dec.
Space Weather Scales
Weekly Highlights and Forecasts
Issued: 2025 Dec 01 0212 UTC
Prepared by the US Dept. of Commerce, NOAA, Space Weather Prediction Center

Highlights of Solar and Geomagnetic Activity
24 - 30 November 2025

Solar activity was at low levels over 24-27 and 30 Nov with C-class
flare activity observed. High levels of solar activity were observed
on 28 Nov when Region 4294 (S15, L=293, class/area=Fkc/1100 on 30
Nov) produced an impulsive M5.9 flare (R2-Moderate) at 28/2222 UTC,
with Type-II (828 km/s) and Tenflare (240 sfu) radio emissions, as
the region rotated onto the disk from the SE limb. Solar activity
reached high levels again on 29 Nov with six M-class flares
(R1-Minor) observed from Region 4294. No Earth-directed CMEs were
detected during the summary period.

No proton events were observed at geosynchronous orbit.

The greater than 2 MeV electron flux at geosynchronous orbit was a
normal to moderate levels on 24-27 Nov, with high levels observed on
28-30 Nov.

Geomagnetic field activity reached active levels on 24 Nov, and G1
(Minor) storm levels on 25 Nov, due to negative polarity CH HSS
influences. Active levels were observed again on 26 Nov as negative
polarity CH HSS influences subsided, followed by the onset of
positive polarity CH HSS influences. Periods of G1 (Minor) storming
were observed on 27 Nov, with periods of active conditions observed
over 28-30 Nov, due to continued positive polarity CH HSS
influences.

Forecast of Solar and Geomagnetic Activity
01 December - 27 December 2025

Solar activity is likely to reach moderate to high levels during the
outlook period. M-class flares (R1-R2/Minor-Moderate) are likely,
with slight chance for X-flares (R3-Strong or greater), through 12
Dec due primarily to the flare potential of Region 4294.

There exists a slight chance for the greater than 10 MeV proton flux
to reach S1 (Minor) solar radiation storm levels through 12 Dec, due
primarily to the eruptive potential of Region 4294.

The greater than 2 MeV electron flux at geosynchronous orbit is
expected to reach high levels on 01-06, 16-17, and 24-27 Dec. Normal
to moderate levels are expected to prevail throughout the remainder
of the outlook period.

Geomagnetic activity is likely to reach active levels on 03 and 06
Dec, and G1 (Minor) storm levels on 04-05 Dec, driven by influences
from a negative polarity CH HSS. Additional G1 storm periods are
likely on 13 Dec, with active levels likely on 14 Dec, again
associated with negative polarity CH HSS effects. Active conditions
are likely on 21 Dec, followed by G1 storm levels on 22 Dec, in
response to negative polarity CH HSS influences. Further G1 storm
periods are likely on 23-26 Dec, with active levels likely on 27
Dec, due to positive polarity CH HSS influences. Quiet and quiet to
unsettled conditions are expected to prevail throughout the
remainder of the outlook period.
Space Weather Scales
About AIA Images
The Atmospheric Imaging Assembly (AIA) on the Solar Dynamics Observatory (SDO) is designed to provide an unprecedented view of the solar corona, taking images that span at least 1.3 solar diameters in multiple wavelengths nearly simultaneously, at a resolution of ~ 1 arcsec and at a cadence of 10 s or better. The primary goal of the AIA Science Investigation is to use these data, together with data from other SDO instruments and from other observatories, to significantly improve our understanding of the physics behind the activity displayed by the Sun's atmosphere, which drives space weather in the heliosphere and in planetary environments. The AIA will produce data required for quantitative studies of the evolving coronal magnetic field, and the plasma that it holds, both in quiescent phases and during flares and eruptions; the AIA science investigation aims to utilize these data in a comprehensive research program to provide new understanding of the observed processes
Left Click Image for screen size, Right Click Image and open in new tab for full size.
Daily Image AIA 171
Channel | Region of atmosphere | Primary ion(s)
171Ã… | quiet corona, upper transition region | Fe IX
Daily Image AIA 171 PFSS Model
Channel | Region of atmosphere | Primary ion(s)
171Ã… | quiet corona, upper transition region | Fe IX
Daily Image AIA 193
Channel | Region of atmosphere | Primary ion(s)
193Ã… | corona and hot flare plasma | Fe XII, XXIV
Daily Image AIA 304
Channel | Region of atmosphere | Primary ion(s)
304Ã… | chromosphere, transition region | He II
Daily Video AIA 171
Daily Video AIA 171 PFSS Model
Daily Video AIA 193
Daily Video AIA 304
About the HMI Images
(Helioseismic and Magnetic Imager)
HMI is an instrument designed to study oscillations and the magnetic field at the solar surface, or photosphere. HMI is one of three instruments on the Solar Dynamics Observatory; together, the suite of instruments observes the Sun nearly continuously and takes a terabyte of data a day. HMI observes the full solar disk at 6173 Ã… with a resolution of 1 arcsecond. HMI is a successor to the Michelson Doppler Imager on the Solar and Heliospheric Observatory. This is very much how the Sun looks like in the visible range of the spectrum (for example, looking at it using special 'eclipse' glasses: Remember, do not ever look directly at the Sun!). The magnetogram image shows the magnetic field in the solar photosphere, with black and white indicating opposite polarities.
Left Click Image for screen size, Right Click Image and open in new tab for full size.
Daily Image HMI Continuum
Daily Image HMI Magnetogram
About LASCO Images
LASCO (Large Angle Spectrometric Coronagraph) is able to take images of the solar corona by blocking the light coming directly from the Sun with an occulter disk, creating an artificial eclipse within the instrument itself. The position of the solar disk is indicated in the images by the white circle. The most prominent feature of the corona are usually the coronal streamers, those nearly radial bands that can be seen both in C2 and C3. Occasionally, a coronal mass ejection can be seen being expelled away from the Sun and crossing the fields of view of both coronagraphs. The shadow crossing from the lower left corner to the center of the image is the support for the occulter disk.
C2 images show the inner solar corona up to 8.4 million kilometers (5.25 million miles) away from the Sun.
C3 images have a larger field of view: They encompass 32 diameters of the Sun. To put this in perspective, the diameter of the images is 45 million kilometers (about 30 million miles) at the distance of the Sun, or half of the diameter of the orbit of Mercury. Many bright stars can be seen behind the Sun.
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Combined C2 C3 and AIA 304
Log Polar View C2 C3 and AIA 304
Combined C2 C3 and AIA 304 Video
Log Polar View C2 C3 and AIA 304 Video
Space Weather Videos
Space Weather Information

Demystifying Space Weather

An article by Scientific Frontline
Informative information and glossary about “Space Weather”

Space weather has become increasingly important in our modern world due to our growing reliance on technology. It can impact various aspects of our daily lives, from communication and navigation systems to power grids and even astronaut safety. In this deep dive, we'll explore the intricacies of space weather, its causes, its effects, and why understanding it is crucial in our technology-dependent society.



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