:Product: 3-Day Forecast
:Issued: 2026 Jul 03 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 Jul 03-Jul 05 2026 is 5.67 (NOAA Scale
G2).

NOAA Kp index breakdown Jul 03-Jul 05 2026

             Jul 03       Jul 04       Jul 05
00-03UT       1.00         5.67 (G2)    2.67     
03-06UT       1.00         4.67 (G1)    2.33     
06-09UT       1.00         4.33         2.33     
09-12UT       1.33         4.33         2.33     
12-15UT       5.67 (G2)    3.67         2.33     
15-18UT       4.67 (G1)    3.67         2.33     
18-21UT       4.67 (G1)    3.33         4.67 (G1)
21-00UT       5.00 (G1)    2.33         5.00 (G1)

Rationale: CME arrival from the event on 30 June is likely to bring G1
(Minor) geomagnetic storm conditions, with a chance for G2 (Moderate)
levels beginning on 03 July and continuing into 04 Jul. Further CME
activity from 01-02 Jul, combined with possible influences from +CH72,
are likely to bring active to additional G1 (Minor) storm conditions,
with an isolated period of G2 (Moderate) levels possible.

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 03-Jul 05 2026

              Jul 03  Jul 04  Jul 05
S1 or greater   10%     10%     10%

Rationale: There is a slight chance for a greater than 10 MeV proton
event (S1-Minor) due to the flare potential of Regions 4478 and 4479 on
03-05 Jul.

C. NOAA Radio Blackout Activity and Forecast

Radio blackouts reaching the R1 levels were observed over the past 24
hours. The largest was at Jul 02 2026 2312 UTC.

Radio Blackout Forecast for Jul 03-Jul 05 2026

              Jul 03        Jul 04        Jul 05
R1-R2           65%           65%           65%
R3 or greater   15%           15%           15%

Rationale: R1-R2 (Minor-Moderate) radio blackouts are likely, with a
slight chance for an isolated R3 (Strong) event through 05 Jul.