:Product: 3-Day Forecast
:Issued: 2026 Aug 01 0030 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 Aug 01-Aug 03 2026 is 5.67 (NOAA Scale
G2).

NOAA Kp index breakdown Aug 01-Aug 03 2026

             Aug 01       Aug 02       Aug 03
00-03UT       3.00         4.00         3.33     
03-06UT       2.33         4.33         4.00     
06-09UT       2.00         5.67 (G2)    3.00     
09-12UT       1.33         4.33         2.33     
12-15UT       3.00         5.00 (G1)    3.00     
15-18UT       3.00         3.00         1.00     
18-21UT       3.67         1.67         1.00     
21-00UT       4.00         1.67         0.67     

Rationale: G1-G2 (Minor-Moderate) geomagnetic storms are likely on 02
Aug due to the anticipated arrival of CME that left the Sun on 30 Jul.

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 (S1 - Minor level).

Solar Radiation Storm Forecast for Aug 01-Aug 03 2026

              Aug 01  Aug 02  Aug 03
S1 or greater   75%     25%      10%

Rationale: S1 (Minor) solar radiation storms are expected on 01 Aug.
There is a chance for S1 (Minor) radiation storms on 02 Aug and a slight
chance on 03 Aug.

C. NOAA Radio Blackout Activity and Forecast

No radio blackouts were observed over the past 24 hours.

Radio Blackout Forecast for Aug 01-Aug 03 2026

              Aug 01        Aug 02        Aug 03
R1-R2           35%           35%           35%
R3 or greater    5%            5%            5%

Rationale: There is a chance for R1 (Minor) radio blackouts on 01-03
Aug.