Space Weather Observations, Alerts, and Forecast

3-day Solar-Geophysical Forecast

:Product: 3-Day Forecast
:Issued: 2026 Sep 06 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 1 (below NOAA
Scale levels).
The greatest expected 3 hr Kp for Sep 06-Sep 08 2026 is 4.67 (NOAA Scale
G1).

NOAA Kp index breakdown Sep 06-Sep 08 2026

             Sep 06       Sep 07       Sep 08
00-03UT       1.33         3.33         4.00     
03-06UT       1.33         2.00         4.00     
06-09UT       1.33         2.00         4.67 (G1)
09-12UT       1.33         3.00         4.67 (G1)
12-15UT       1.33         3.00         4.67 (G1)
15-18UT       1.33         3.33         4.00     
18-21UT       1.33         3.67         3.67     
21-00UT       1.67         4.00         3.33     

Rationale: Isolated G1 (Minor) periods are likely if the CMEs from 05
Sep impact Earth as forecast.

B. NOAA Solar Radiation Activity Observation and Forecast

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

Solar Radiation Storm Forecast for Sep 06-Sep 08 2026

              Sep 06  Sep 07  Sep 08
S1 or greater   75%     10%     10%

Rationale: The greater than 10 MeV proton flux is expected to continue
decreasing towards background levels through early 08 Sep, with a slight
chance for S1 (Minor) levels over the next three days.

C. NOAA Radio Blackout Activity and Forecast

Radio blackouts reaching the R1 levels were observed over the past 24
hours. The largest was at Sep 05 2026 1518 UTC.

Radio Blackout Forecast for Sep 06-Sep 08 2026

              Sep 06        Sep 07        Sep 08
R1-R2           20%           20%           20%
R3 or greater    5%            5%            5%

Rationale: There is a slight chance for R1-R2 (Minor-Moderate) radio
blackouts through 08 Sep.

Real Time Images of the Sun

SOHO EIT 304

SOHO EIT 284

The sun is constantly monitored for sun spots and coronal mass ejections. EIT (Extreme ultraviolet Imaging Telescope) images the solar atmosphere at several wavelengths, and therefore, shows solar material at different temperatures. In the images taken at 304 Angstrom the bright material is at 60,000 to 80,000 degrees Kelvin. In those taken at 171 Angstrom, at 1 million degrees. 195 Angstrom images correspond to about 1.5 million Kelvin, 284 Angstrom to 2 million degrees. The hotter the temperature, the higher you look in the solar atmosphere.

Real Time Solar X-ray and Solar Wind

Latest LASCO Solar Corona Large Angle and Spectrometric Coronagraph (LASCO).

Real-Time Solar Wind Real-Time Solar Wind data broadcast from NASA's ACE satellite.

Space Weather Overview

The Solar Cycle is observed by counting the frequency and placement of sunspots visible on the Sun. Solar cycle 25 started in December, 2019 and is expected to complete around 2030, approximately 11 years.

Auroral Activity Extrapolated from NOAA POES

Northern Hemi Auroral Map

Southern Hemi Auroral Map

Instruments on board the NOAA Polar-orbiting Operational Environmental Satellite (POES) continually monitor the power flux carried by the protons and electrons that produce aurora in the atmosphere. SWPC has developed a technique that uses the power flux observations obtained during a single pass of the satellite over a polar region (which takes about 25 minutes) to estimate the total power deposited in an entire polar region by these auroral particles. The power input estimate is converted to an auroral activity index that ranges from 1 to 10.

VHF and HF Band Conditions

Credits: