240
FXXX10 KWNP 200031
DAYTDF

:Product: 3-Day Forecast
:Issued: 2026 Jul 20 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 1 (below NOAA
Scale levels).
The greatest expected 3 hr Kp for Jul 20-Jul 22 2026 is 5.00 (NOAA Scale
G1).

NOAA Kp index breakdown Jul 20-Jul 22 2026

             Jul 20       Jul 21       Jul 22
00-03UT       1.33         1.33         4.00
03-06UT       2.00         2.00         4.00
06-09UT       2.00         2.00         4.00
09-12UT       1.33         1.33         4.33
12-15UT       1.67         1.33         5.00 (G1)
15-18UT       0.67         2.33         5.00 (G1)
18-21UT       0.67         3.00         4.67 (G1)
21-00UT       1.33         4.00         4.33

Rationale: G1 (Minor) geomagnetic storms are likely on 22 Jul due to the
anticipated onset of influence from a negative 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 Jul 20-Jul 22 2026

              Jul 20  Jul 21  Jul 22
S1 or greater    1%      1%      1%

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 Jul 20-Jul 22 2026

              Jul 20        Jul 21        Jul 22
R1-R2           15%           15%           15%
R3 or greater    1%            1%            1%

Rationale: There remains a chance for R1-R2 (Minor-Moderate) radio
blackouts over 20-22 Jul.