322
FXXX10 KWNP 111231
DAYTDF

:Product: 3-Day Forecast
:Issued: 2026 Jun 11 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 Jun 11-Jun 13 2026 is 5.00 (NOAA Scale
G1).

NOAA Kp index breakdown Jun 11-Jun 13 2026

             Jun 11       Jun 12       Jun 13
00-03UT       1.33         3.67         3.00
03-06UT       2.33         4.00         2.00
06-09UT       3.00         4.00         2.00
09-12UT       3.33         2.33         2.67
12-15UT       3.00         2.00         2.67
15-18UT       3.00         2.67         2.67
18-21UT       3.00         2.00         4.33
21-00UT       2.67         2.33         5.00 (G1)

Rationale: Unsettled to active conditions are anticipated on 12 June
with -CH HSS onset. Active to G1 (Minor) storming levels are anticipated
on 13 June due to the persistence of the high-speed stream and the
arrival of glancing CME influences.

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 11-Jun 13 2026

              Jun 11  Jun 12  Jun 13
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 Jun 11-Jun 13 2026

              Jun 11        Jun 12        Jun 13
R1-R2           35%           35%           35%
R3 or greater    5%            5%            5%

Rationale: There is a chance for R1-R2 (Minor-Moderate) radio blackouts,
with a slight chance for R3 (Strong) or greater events through 13 Jun
primarily due to regions 4465 and 4464.