370
FXXX10 KWNP 180031
DAYTDF

:Product: 3-Day Forecast
:Issued: 2026 Jan 18 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 5 (NOAA Scale
G1).
The greatest expected 3 hr Kp for Jan 18-Jan 20 2026 is 4.67 (NOAA Scale
G1).

NOAA Kp index breakdown Jan 18-Jan 20 2026

             Jan 18       Jan 19       Jan 20
00-03UT       4.33         4.00         3.67
03-06UT       4.67 (G1)    3.67         3.67
06-09UT       4.00         3.33         3.33
09-12UT       3.00         3.00         3.00
12-15UT       3.00         3.00         2.00
15-18UT       3.33         3.33         2.67
18-21UT       3.67         3.33         3.00
21-00UT       3.67         4.00         3.33

Rationale: G1 (Minor) geomagnetic storms are expected on 18 Jan due to
influence from a positive polarity coronal hole.

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 Jan 18-Jan 20 2026

              Jan 18  Jan 19  Jan 20
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

Radio blackouts reaching the R1 levels were observed over the past 24
hours. The largest was at Jan 17 2026 1029 UTC.

Radio Blackout Forecast for Jan 18-Jan 20 2026

              Jan 18        Jan 19        Jan 20
R1-R2           55%           55%           55%
R3 or greater    5%            5%            5%

Rationale: R1-R2 (Minor-Moderate) radio blackouts are likely, with a
slight chance of R3 (Strong), over 18-20 Jan due to the flare potential
from multiple complex regions on the solar disk.