:Product: 3-Day Forecast
:Issued: 2026 Jul 17 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 Jul 17-Jul 19 2026 is 3.00 (below NOAA
Scale levels).

NOAA Kp index breakdown Jul 17-Jul 19 2026

             Jul 17       Jul 18       Jul 19
00-03UT       1.00         2.33         1.67     
03-06UT       1.33         3.00         2.00     
06-09UT       0.67         1.67         1.67     
09-12UT       1.67         1.67         1.33     
12-15UT       1.67         1.00         0.67     
15-18UT       1.67         1.00         0.67     
18-21UT       2.00         2.00         1.67     
21-00UT       2.00         2.33         1.67     

Rationale: No G1 (Minor) or greater geomagnetic storms are expected
through 19 Jul.

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 17-Jul 19 2026

              Jul 17  Jul 18  Jul 19
S1 or greater    1%      1%      1%

Rationale: No S1 (Minor) or greater solar radiation storms are expected
through 19 Jul.  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 17-Jul 19 2026

              Jul 17        Jul 18        Jul 19
R1-R2           25%           25%           25%
R3 or greater    1%            1%            1%

Rationale: There is a chance for R1-R2 (Minor-Moderate) radio blackouts
through 19 Jul.