. Scientific Frontline: Space Weather

Space Weather


Warnings and Alerts
Issue Time: 2025 Dec 09 1210 UTC

CONTINUED ALERT: Electron 2MeV Integral Flux exceeded 1000pfu
Continuation of Serial Number: 3574
Begin Time: 2025 Dec 05 1530 UTC
Yesterday Maximum 2MeV Flux: 1040 pfu

Potential Impacts: Satellite systems may experience significant charging resulting in increased risk to satellite systems.
Space Weather Scales
Current Condition and Alerts
Issued: 2025 Dec 09 1210 UTC
Prepared by the US Dept. of Commerce, NOAA, Space Weather Prediction Center

Geophysical Alert Message

Solar-terrestrial indices for 08 December follow.
Solar flux 186 and estimated planetary A-index 2.
The estimated planetary K-index at 1200 UTC on 09 December was 1.00.

Space weather for the past 24 hours has been minor.
Radio blackouts reaching the R1 level occurred.

Space weather for the next 24 hours is predicted to be strong.
Geomagnetic storms reaching the G3 level are likely.
Radio blackouts reaching the R2 level are likely.
Space Weather Scales
Forecast Discussion
Issued: 2025 Dec 09 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. Region 4298 (S16W64, Cso/beta)
produced an impulsive X1.1/2b (R3-Strong) flare at 08/0501 UTC. Region
4299 (N22W25, Dai/beta-gamma-delta) produced an M2.4/2n (R1-Minor) flare
at 08/0012 UTC and an M1.8/1n (R1-Minor) flare at 08/0654 UTC.

Region 4294 (S16W42, Ekc/beta-gamma-delta) produced an an M2.0 flare at
08/0036 UTC and an M1.1 at 08/1305 UTC. Enhanced flux emergence in its
leading spots and intermediate region brought about a larger area and
sunspot count. This region also produced and M3.2 flare at
08/2117 UTC at the same time that Region 4304 was also flaring and
possibly contributing to the observed X-ray enhancement. Similar
situation happened at 08/2228 UTC, when an M1.2 was measured while both
Regions 4294 and 4299 were simultaneously flaring.

Eruptions from the M1.8/1n flare at 08/0012 UTC and the X1.1/2b flare at
08/0501 UTC both appeared to be reabsorbed with no discernible CME
activity.

.Forecast...
M-class flares (R1-R2/Minor-Moderate) are likely over 09-11 Dec, with a
slight chance for X-class flares (R3/Strong) This is based on 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 has been at high levels, reaching a
peak of 1039 pfu. The greater than 10 MeV proton flux has been at
background.

.Forecast...
The greater than 2 MeV electron flux is expected to reach high levels on
09 Dec, and then decrease to normal to moderate levels on 10-11 Dec.

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


Solar Wind

.24 hr Summary...
Solar wind parameters reflected nominal conditions. There was a weak
enhancement, but it rendered nothing. The total field remained around 7
nT with the Bz component oscillating between +/-3 nT. Solar wind speeds
were between 340-440 km/s. The phi angle remained in the negative
sector.

.Forecast...
The solar wind environment is expected to become enhanced due to the
arrival of a CME that left the Sun on 06 Dec. Expected arrival in 09
Dec, waning conditions are expected into 11 Dec.

Geospace

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

.Forecast...
G3 (Strong) geomagnetic storm levels are likely
on 09 Dec due to the anticipated influence of the CME that left the Sun
on 06 Dec. G1 conditions on 10 Dec are likely due to waning CME effects.
Space Weather Scales
Three Day Forecast
Issued: 2025 Dec 09 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 2 (below NOAA
Scale levels).
The greatest expected 3 hr Kp for Dec 09-Dec 11 2025 is 6.67 (NOAA Scale
G3).

NOAA Kp index breakdown Dec 09-Dec 11 2025

Dec 09 Dec 10 Dec 11
00-03UT 2.33 5.33 (G1) 2.67
03-06UT 0.67 5.00 (G1) 2.00
06-09UT 1.00 5.00 (G1) 2.33
09-12UT 1.00 4.33 2.33
12-15UT 6.67 (G3) 4.00 2.33
15-18UT 5.33 (G1) 3.67 2.33
18-21UT 5.00 (G1) 3.67 2.33
21-00UT 3.67 1.33 2.67

Rationale: Periods of G2-G3 (Moderate-Strong) geomagnetic storms are
likely on 09 Dec, due to the anticipated influence of a CME from Dec 06.

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 09-Dec 11 2025

Dec 09 Dec 10 Dec 11
S1 or greater 15% 15% 15%

Rationale: There is a slight chance for S1 (Minor) or greater solar
radiation storms on 09-11 Dec.

C. NOAA Radio Blackout Activity and Forecast

Radio blackouts reaching the R1 levels were observed over the past 24
hours. The largest was at Dec 08 2025 2117 UTC.

Radio Blackout Forecast for Dec 09-Dec 11 2025

Dec 09 Dec 10 Dec 11
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 09-11 Dec.
Space Weather Scales
Weekly Highlights and Forecasts
Issued: 2025 Dec 08 0210 UTC
Prepared by the US Dept. of Commerce, NOAA, Space Weather Prediction Center

Highlights of Solar and Geomagnetic Activity
01 - 07 December 2025

Solar activity reached high levels this period. Region 4299 (N21,
L=268, class/area=Dai/220 on 07 Dec) produced an X1.9/1n flare at
01/0249 UTC; the strongest flare of the period. Other notable
activity included an M8.1/2b flare at 06/2039 UTC, also from Region
4299, which produced an full-halo CME that is expected to arrive
between late 08 Dec-midday 09 Dec. A CME, first visible in LASCO C2
imagery beginning at 04/0648 UTC off the SE, arrived at Earth late
on 07 Dec.

The greater than 10 MeV proton flux became elevated above background
levels late 06 Dec-late 07 Dec following the M8.1 flare at 06/2039
UTC from AR4299, but did not reach event levels.

The greater than 2 MeV electron flux at geosynchronous orbit was at
normal to moderate levels on 04 Dec, with high levels obserbed
throughout the remainder of the period.

Geomagnetic field activity reached active levels on 01 Dec in
response to positive polarity CH HSS influences. Quiet to unsettled
levels were observed on 02 Dec as CH HSS influences subsided.
Periods of G1-G3 (Minor-Moderate) geomagnetic storming were observed
on 03 Dec, with G1 storm periods observed on 04 Dec, due to CIR and
negative polarity CH HSS influences. Quiet and unsettled levels were
observed on 05 Dec, with active conditions observed on 06 Dec, as
negative polarity CH HSS influences waned. Active levels were
observed again on 07 Dec in response to the passage of a CME from 04
Dec.

Forecast of Solar and Geomagnetic Activity
08 December - 03 January 2026

M-class flares (R1-R2/Minor-Moderate) are likely, with a slight
chance for X-class flares (R3/Strong or greater), through much of
the outlook period.

There is a slight chance for the greater than 10 MeV proton flux to
reach 10 pfu (S1-Minor) through much of the outlook period.

The greater than 2 MeV electron flux is expected to reach high
levels on 08-09, 12-13, 16-17, 25-29 Dec, and 01-03 Jan. Normal to
moderate levels are expected to prevail throughout the remainder of
the outlook period.

Geomagnetic field activity is likely to reach G1 (Minor) storm
levels on 08 and 10 Dec, with G2-G3 (Moderate-Strong) storming
likely on 09 Dec, due to the anticipated arrival and passage of a
CME that left the Sun on 06 Dec. Periods of G1 storming are likely
on 21-23 Dec in response to negative polarity CH HSS influences, and
again on 24-26 Dec under positive polarity CH HSS influences. Period
of G2 (Moderate) storms are likely on 30 Dec, with G1 storming
likely on 31 Dec, when negative polarity CH HSS influences are
anticipated.
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.
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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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