922
FXXX10 KWNP 301231
DAYTDF

:Product: 3-Day Forecast
:Issued: 2026 Mar 30 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 30-Apr 01 2026 is 5.67 (NOAA Scale
G2).

NOAA Kp index breakdown Mar 30-Apr 01 2026

             Mar 30       Mar 31       Apr 01
00-03UT       2.67         3.67         5.00 (G1)
03-06UT       2.67         3.00         4.67 (G1)
06-09UT       3.33         2.67         4.33
09-12UT       3.00         2.00         4.00
12-15UT       2.33         4.67 (G1)    3.00
15-18UT       2.33         5.67 (G2)    2.67
18-21UT       3.00         5.67 (G2)    2.00
21-00UT       3.67         5.00 (G1)    2.33

Rationale: G1 (Minor) geomagnetic storming is likely on 30 Mar due to
recurrent positive polarity CH HSS effects. Enhancements are likely to
be further increased to G2 (Major) levels midday to late on 31 Mar due
to possible CME effects from the 30 Mar X1.4 major flare event. Active
to G1 (Minor) levels are then expected into 01 Apr due to continued CH
HSS and CME effects.

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 30-Apr 01 2026

              Mar 30  Mar 31  Apr 01
S1 or greater   10%     50%     50%

Rationale: The greater than 10 MeV proton flux is likely to exceed event
levels (S1/Minor) on 31 Mar through 01 Apr.

C. NOAA Radio Blackout Activity and Forecast

Radio blackouts reaching the R3 levels were observed over the past 24
hours. The largest was at Mar 30 2026 0319 UTC.

Radio Blackout Forecast for Mar 30-Apr 01 2026

              Mar 30        Mar 31        Apr 01
R1-R2           55%           55%           55%
R3 or greater   10%           10%           10%

Rationale: Solar activity is expected to be low with M-class flares
(R1-R2/Minor-Moderate) likely through 01 Apr and a slight chance of
X-class flares (R3/Strong) through 01 Apr.