480
FXXX10 KWNP 040031
DAYTDF

:Product: 3-Day Forecast
:Issued: 2025 Jun 04 0030 UTC
# Prepared by the US Dept. of Commerce, NOAA, Space Weather Prediction Center
# Product description and SWPC contact on the Web
# http://www.swpc.noaa.gov/wwire.html
#
#             3-Day Forecast
#
A. NOAA Geomagnetic Activity Observation and Forecast

The greatest observed 3 hr Kp over the past 24 hours was 7 (NOAA Scale
G3).
The greatest expected 3 hr Kp for Jun 04-Jun 06 2025 is 5.00 (NOAA Scale
G1).

NOAA Kp index breakdown Jun 04-Jun 06 2025

             Jun 04       Jun 05       Jun 06
00-03UT       4.00         5.00 (G1)    3.33
03-06UT       4.67 (G1)    4.00         3.33
06-09UT       2.33         3.33         2.00
09-12UT       3.00         3.00         3.00
12-15UT       2.33         2.33         3.00
15-18UT       2.33         2.33         3.33
18-21UT       2.67         3.00         2.00
21-00UT       4.00         3.67         3.33

Rationale: No G1 (Minor) geomagnetic storms are expected should the
current solar wind environment turn favorable again early on 4 Jun. CME
influences are anticipated to cease later on 4 Jun, and a transition
back to a CH HSS regime is expected which will make G1 storm levels
possible again on 5 Jun.

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 Jun 04-Jun 06 2025

              Jun 04  Jun 05  Jun 06
S1 or greater   15%     15%     15%

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

Radio blackouts reaching the R1 levels were observed over the past 24
hours. The largest was at Jun 03 2025 1303 UTC.

Radio Blackout Forecast for Jun 04-Jun 06 2025

              Jun 04        Jun 05        Jun 06
R1-R2           55%           55%           55%
R3 or greater   10%           10%           10%

Rationale: R1 (Minor) radio blackouts are likely due to a few active
regions on the solar disk and their combined solar flare potential.