176
FXXX10 KWNP 211231
DAYTDF

:Product: 3-Day Forecast
:Issued: 2025 Mar 21 1230 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 3 (below NOAA
Scale levels).
The greatest expected 3 hr Kp for Mar 21-Mar 23 2025 is 3.67 (below NOAA
Scale levels).

NOAA Kp index breakdown Mar 21-Mar 23 2025

             Mar 21       Mar 22       Mar 23
00-03UT       3.33         2.00         3.67
03-06UT       3.00         2.00         3.33
06-09UT       2.33         2.33         2.67
09-12UT       2.33         2.67         2.67
12-15UT       2.00         2.00         2.00
15-18UT       2.00         2.67         2.00
18-21UT       2.67         3.33         2.33
21-00UT       3.67         3.67         2.67

Rationale: No G1 (Minor) or greater geomagnetic storms are expected.  No
significant transient or recurrent solar wind features are forecast.

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 Mar 21-Mar 23 2025

              Mar 21  Mar 22  Mar 23
S1 or greater    5%      5%      5%

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

No radio blackouts were observed over the past 24 hours.

Radio Blackout Forecast for Mar 21-Mar 23 2025

              Mar 21        Mar 22        Mar 23
R1-R2           25%           25%           25%
R3 or greater    5%            5%            5%

Rationale: A chance for R1-R2 (Minor-Moderate) radio blackouts due to
M-class flares will persist through 23 Mar.