. Scientific Frontline: Space Weather

Space Weather

Warnings
Space Weather Message Code: WARK04
Serial Number: 5038
Issue Time: 2025 Jul 16 1147 UTC

EXTENDED WARNING: Geomagnetic K-index of 4 expected
Extension to Serial Number: 5037
Valid From: 2025 Jul 16 0240 UTC
Now Valid Until: 2025 Jul 16 2100 UTC
Warning Condition: persistence

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 Scales
Current Condition and Alerts
Issued: 2025 Jul 16 1205 UTC
Prepared by the US Dept. of Commerce, NOAA, Space Weather Prediction Center

Geophysical Alert Message

Solar-terrestrial indices for 15 July follow.
Solar flux 139 and estimated planetary A-index 23.
The estimated planetary K-index at 1200 UTC on 16 July was 3.67.

No space weather storms were observed for the past 24 hours.

Space weather for the next 24 hours is predicted to be minor.
Radio blackouts reaching the R1 level are likely.
Space Weather Scales
Forecast Discussion
Issued: 2025 Jul 16 1230 UTC
Prepared by the U.S. Dept. of Commerce, NOAA, Space Weather Prediction Center

Solar Activity

.24 hr Summary...
Solar activity was at low levels. The largest flare of the period was a
C5.0/Sf at 16/0358 UTC from Region 4143 (N23W05, Dai/beta). Moderate
growth was observed in Regions 4139 (N22W35, Dai/beta-gamma), 4142
(N01E28, Dai/beta-gamma), and 4143. Both 4142 and 4143 contributed to
the C-class activity. Only minor growth was observed in Regions 4136
(N19W21, Cko/beta-gamma) and 4145 (S26E14, Cro/beta). The rest of the
spotted regions were either stable or in decay. No Earth-directed CMEs
were observed.

.Forecast...
Solar activity is expected to be low with moderate levels likely (R1-R2,
Minor-Moderate) on 16-18 Jul due to the flare potential of Regions 4139,
4142, and 4143.

Energetic Particle

.24 hr Summary...
The greater than 2 MeV electron flux reached high levels with a peak
flux of 1,800 pfu at 15/1545 UTC.

The greater than 10 MeV proton flux remained at background levels.

.Forecast...
Continued influence from the coronal hole (CH) high speed stream (HSS)
will maintain higher than normal electron flux at geostationary orbit
through 18 Jul. The greater than 2 MeV flux will be moderate to high,
especially during the diurnal maxima, during this time.

The greater than 10 MeV proton flux is expected to continue at
background levels through 18 Jul.

Solar Wind

.24 hr Summary...
Solar wind parameters continued to be enhanced under positive polarity
CH HSS influence. Total field was between 2-8 nT with the Bz component
oscillating between +7/-6 nT. Solar wind speeds averaged around 600
km/s. Phi angle was predominantly in the positive sector with brief
oscillations into the negative sector.

.Forecast...
Solar wind parameters are expected to continue to be enhanced under CH
HSS influence through 18 Jul.

Geospace

.24 hr Summary...
The geomagnetic field was quiet to active.

.Forecast...
Quiet to unsettled levels, with isolated active periods possible, are
expected through 18 Jul as HSS conditions persist.
Space Weather Scales
Three Day Forecast
Issued: 2025 Jul 16 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 Jul 16-Jul 18 2025 is 3.67 (below NOAA
Scale levels).

NOAA Kp index breakdown Jul 16-Jul 18 2025

Jul 16 Jul 17 Jul 18
00-03UT 3.00 3.00 3.00
03-06UT 3.00 2.67 2.67
06-09UT 2.67 2.00 2.33
09-12UT 3.67 1.67 1.67
12-15UT 2.67 2.00 1.33
15-18UT 2.00 2.00 1.33
18-21UT 2.33 1.67 1.67
21-00UT 2.67 2.00 2.00

Rationale: No G1 (Minor) or greater geomagnetic storms are expected. No
significant transient or recurrent solar wind features are forecast.

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 Jul 16-Jul 18 2025

Jul 16 Jul 17 Jul 18
S1 or greater 1% 1% 1%

Rationale: No S1 (Minor) or greater solar radiation storms are expected.
No significant active region activity favorable for radiation storm
production is forecast.

C. NOAA Radio Blackout Activity and Forecast

No radio blackouts were observed over the past 24 hours.

Radio Blackout Forecast for Jul 16-Jul 18 2025

Jul 16 Jul 17 Jul 18
R1-R2 60% 60% 60%
R3 or greater 5% 5% 5%

Rationale: Solar activity is expected to be low with moderate levels
likely (R1-R2, Minor-Moderate) on 16-18 Jul due to the flare potential
of Regions 4139, 4142, and 4143.
Space Weather Scales
Weekly Highlights and Forecasts
Issued: 2025 Jul 14 0702 UTC
Prepared by the US Dept. of Commerce, NOAA, Space Weather Prediction Center

Highlights of Solar and Geomagnetic Activity
07 - 13 July 2025

Solar activity was ranged from low to moderate levels. R1 (Minor)
events were observed on 08-09 Jul and 12 Jul. The largest was an
M2.4 flare at 08/0417 UTC from Region 4136 (N19, L=022,
class/area=Dai/220 on 11 Jul). Region 4140 (S15, L=348,
class/area=Dao/130 on 12 Jul) produced a similarly powerful M2.3/1f
flare at 12/0834 UTC. The other 15 numbered active regions on the
visible disk were either quiet or only produced C-class activity. No
Earth-directed CMEs were observed in available coronagraph imagery.

No proton events were observed at geosynchronous orbit.

The greater than 2 MeV electron flux at geosynchronous orbit reached
high levels on 09-10 Jul following elevated wind speeds from a
coronal hole. The remainder of the summary period was at normal to
moderate levels.

Geomagnetic field activity was varied from quiet to G1 (Minor)
geomagnetic storm levels. G1 conditions were observed early on 07
Jul, with a slow decrease to active levels on 08 Jul and unsettled
levels on 09 Jul due to influence from a negative polarity coronal
hole. Active conditions were observed on 11 Jul and unsettled
conditions on 12 Jul were in response to the onset of a positive
polarity coronal hole. G1 conditions observed on 13 Jul followed a
pronounced increase in solar wind speeds from a mildly elevated ~500
km/s on 12 Jul to a peak just over 700 km/s on 13 Jul.

Forecast of Solar and Geomagnetic Activity
14 July - 09 August 2025

Solar activity is likely to be at low levels, with a chance for
R1-R2 (Minor-Moderate) radio blackouts, over next 27 days due to
several complex active regions on the visible disk and the
anticipated return of multiple active regions from the Sun's
farside.

No proton events are expected at geosynchronous orbit.

The greater than 2 MeV electron flux at geosynchronous orbit is
expected to reach high levels on 20-28 Jul and 05-06 Aug following
activity from recurrent coronal holes. The remainder of the outlook
is likely to be at normal to moderate levels.

Geomagnetic field activity is likely observed mild elevations,
mostly in response to recurrent coronal hole features. Active
conditions are likely on 14 Jul, 22-24 Jul, 02-04 Aug, and 07-09
Aug. Unsettled conditions are likely on 15-17 Jul, 25 Jul, and 01
Aug. The remaining days of the outlook period are expected to be
mostly quiet.
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)
171Å | quiet corona, upper transition region | Fe IX
Daily Image AIA 171 PFSS Model
Channel | Region of atmosphere | Primary ion(s)
171Å | quiet corona, upper transition region | Fe IX
Daily Image AIA 193
Channel | Region of atmosphere | Primary ion(s)
193Å | corona and hot flare plasma | Fe XII, XXIV
Daily Image AIA 304
Channel | Region of atmosphere | Primary ion(s)
304Å | 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 Å 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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