Routine Space Environment Product (Daily)
Issued by NWS
Issued by NWS
110
FXXX10 KWNP 181231
DAYTDF
:Product: 3-Day Forecast
:Issued: 2026 Jul 18 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 2 (below NOAA
Scale levels).
The greatest expected 3 hr Kp for Jul 18-Jul 20 2026 is 2.67 (below NOAA
Scale levels).
NOAA Kp index breakdown Jul 18-Jul 20 2026
Jul 18 Jul 19 Jul 20
00-03UT 1.67 1.67 1.33
03-06UT 1.00 2.00 1.33
06-09UT 2.67 1.67 1.33
09-12UT 2.00 1.33 1.33
12-15UT 1.67 0.67 1.67
15-18UT 1.00 0.67 1.67
18-21UT 1.00 1.67 1.67
21-00UT 2.00 1.67 1.33
Rationale: No G1 (Minor) or greater geomagnetic storms are expected
through 20 Jul.
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 18-Jul 20 2026
Jul 18 Jul 19 Jul 20
S1 or greater 1% 1% 1%
Rationale: No S1 (Minor) or greater solar radiation storms are expected
through 20 Jul. 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 18-Jul 20 2026
Jul 18 Jul 19 Jul 20
R1-R2 15% 15% 15%
R3 or greater 1% 1% 1%
Rationale: There is a slight chance for R1-R2 (Minor-Moderate) radio
blackouts through 20 Jul.