|
|
| Warnings and Alerts | |
| No Current Warnings Space Weather Scales | |
| Current Condition and Alerts | |
|
Issued: 2026 May 31 1205 UTC
Prepared
by the US Dept. of Commerce, NOAA, Space Weather Prediction
Center
Geophysical Alert Message Solar-terrestrial indices for 30 May follow. Solar flux 142 and estimated planetary A-index 15. The estimated planetary K-index at 1200 UTC on 31 May was 1.67. No space weather storms were observed for the past 24 hours. No space weather storms are predicted for the next 24 hours. Space Weather Scales |
|
| Forecast Discussion | |
|
Issued: 2026 May 31 1230 UTC
Prepared
by the U.S. Dept. of Commerce, NOAA, Space Weather Prediction
Center
Solar Activity .24 hr Summary... Solar activity remained at low levels with weak C-class flare activity observed from Regions 4447 (S17W61, Hsx/alpha), 4449 (S09W23, Cso/beta), 4452 (N10W68, Dai/beta-gamma), and 4457 (S10W07, Cro/beta). Region 4447 produced a C3.1 flare at 31/0209 UTC, the largest event of the period. Region 4452 exhibited decay primarily in its leading spots, but managed to maintain a mixed polarity magnetic configuration. Region 4455 (N15E31, Dho/beta) gained additional spots, but lacked any significant flare activity. Region 4457 rapidly emerged and was subsequently numbered. The remaining active regions remained relatively stable and quiet. A faint and narrow CME, associated with a C4.8 flare event at 30/1153 UTC from Region 4446 (S15W28, Cho/beta) is undergoing modeling efforts for any potential impacts to Earth. .Forecast... Solar activity is expected to be at low to moderate levels through 02 Jun with a chance for isolated M-class flare activity. Energetic Particle .24 hr Summary... The greater than 2 MeV electron flux at geosynchronous orbit was at low to moderate levels. The greater than 10 MeV proton flux at geosynchronous orbit remained at background levels. .Forecast... The greater than 2 MeV electron flux is expected to remain at low to moderate levels through 31 May with a chance for high levels on 01 and 02 Jun. The greater than 10 MeV proton flux is expected to remain at background levels through 02 Jun. Solar Wind .24 hr Summary... Solar wind parameters reflected continued negative polarity CH HSS influences. Total field increased to 10-11 nT. The Bz component of the IMF underwent a few sustained southward deflections reaching -7 to -10 nT. Solar wind speeds increased from about 425 km/s to near 560 km/s by the end of the period. Phi angle was in a predominately negative sector. .Forecast... Negative polarity CH HSS influences are expected to continue through 01 Jun with possible glancing influences from the slow eruptions that departed the Sun on 27 and 28 May. Ambient-like conditions are expected to return by the close of 02 Jun. Geospace .24 hr Summary... The geomagnetic field was at quiet to active levels in response to negative polarity CH HSS influences. .Forecast... Unsettled to active conditions, with a chance for isolated G1 (Minor) levels, are expected on 31 May due to negative polarity CH HSS effects. Chances for isolated G1 (Minor) storm periods increase on 31 May with any glancing influences from the aforementioned 27-28 May CMEs. Quiet to active levels are expected to continue into the early to mid portions of 01 Jun as negative polarity CH HSS effects wane with mostly quiet conditions prevailing on 02 Jun. Space Weather Scales |
|
| Three Day Forecast | |
|
Issued: 2026 May 31 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 May 31-Jun 02 2026 is 4.00 (below NOAA Scale levels). NOAA Kp index breakdown May 31-Jun 02 2026 May 31 Jun 01 Jun 02 00-03UT 3.67 3.67 2.33 03-06UT 3.00 3.00 2.00 06-09UT 2.00 2.67 1.67 09-12UT 1.67 2.00 1.33 12-15UT 2.33 2.67 1.00 15-18UT 2.67 2.00 1.67 18-21UT 4.00 2.67 1.67 21-00UT 3.67 2.67 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 May 31-Jun 02 2026 May 31 Jun 01 Jun 02 S1 or greater 5% 5% 5% 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 May 31-Jun 02 2026 May 31 Jun 01 Jun 02 R1-R2 25% 25% 25% R3 or greater 5% 5% 5% Rationale: There is a chance for R1-R2 (Minor-Moderate) radio blackouts over 31 May-02 Jun. Space Weather Scales |
|
| Weekly Highlights and Forecasts | |
|
Issued: 2026 May 25 0601 UTC
Prepared
by the US Dept. of Commerce, NOAA, Space Weather Prediction
Center
Highlights of Solar and Geomagnetic Activity 18 - 24 May 2026 Solar activity ranged from low to moderate levels. The largest flare was an M2.3 (R1-Minor) at 22/1029 UTC from Region 4436 (N18, L=333, class/area Dai/200 on 13 May). The region was also responsible for a C8.3 and C9.5 flares on 21/1814 UTC and 21/1825 UTC, respectively. This region was responsible for the majority of the C-class activity until its rotation off the W limb on 21 May. On 23-24 May, the majority of the C-class activity occurred from Region 4446 (S13, L=141, class/area Dko/280 on 24 May). No Earth-directed CMEs were observed during the period. No proton events were observed at geosynchronous orbit. The greater than 2 MeV electron flux at geosynchronous orbit reached high levels on 18-24 May due to CH HSS influences. The highest flux observed was 6,667 pfu at 18/1435 UTC. Geomagnetic field activity ranged from quiet to active levels. Solar wind parameters began the period in a slow decline from 560 km/s as negative polarity CH HSS effects gradually diminished. At 19/0630 UTC, a small shock was observed increasing total field to 7-8 nT while solar wind speed increased to near 625 km/s before beginning to decline once again. This was likely the glancing effects from a CME that left the Sun on 16 May. Solar wind speed continued to decrease to nominal levels through 22 May. The geomagnetic field reacted with quiet to active levels on 19 May. Quiet to unsettled levels were observed on 18 May and 20-22 May. Quiet conditions occurred on 23-24 May. Forecast of Solar and Geomagnetic Activity 25 May - 20 June 2026 Solar activity is expected to be at low to moderate levels (R1-R2, Minor-Moderate) on 25 May through 07 Jun with the return of old Region 4432 (N14, L=081). Mostly low levels with a chance for M-class flares is expected from 08-20 Jun. 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 25-27 May and 12-20 Jun due to CH HSS influences. Geomagnetic field activity is expected to be at unsettled to active levels on 27-29 May, 04 Jun, 09 Jun, and 11-15 Jun due to recurrent CH HSS activity. G2 (Moderate) storm conditions are likely on 11 Jun and G1 (Minor) storming on 12 Jun due to CIR/CH HSS onset. 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 | |
 |
|
| Daily Image AIA 171 PFSS Model | |
 |
|
| Daily Image AIA 193 | |
 |
|
| Daily Image AIA 304 | |
 |
|
| 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. 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 | |
 |
|
| Daily Video HMI Continuum | |
 |
|
| Daily Video 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. Left Click Image for screen size, Right Click Image and open in new tab for full size. | |
| 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. |
.jpg)