Coronal Hole May Double Solar Wind to 700 km/s, Raising G2 Aurora Chance by July 22
Updated
Updated · Tech Times · Jul 21
Coronal Hole May Double Solar Wind to 700 km/s, Raising G2 Aurora Chance by July 22
3 articles · Updated · Tech Times · Jul 21
Summary
NOAA-linked modeling shows a large transequatorial coronal hole could lift solar wind from about 325 km/s to roughly 700 km/s by July 22, with geomagnetic conditions rising from quiet now to G1 and possibly G2.
That fast stream is forecast to form a corotating interaction region as it overtakes slower solar wind, a setup forecasters can track days ahead—unlike CME storms whose magnetic orientation is unknown until 15 to 60 minutes before impact.
July 22 is the best aurora window, with Seattle, Edinburgh and Oslo among the mid-latitude cities that could see displays if G2 intervals develop; July 21 is expected to be weaker, around unsettled to active conditions.
G1 to G2 storms can bring minor satellite drag, weak grid fluctuations, voltage alarms at high latitudes and some HF radio fading, though operators have unusual multi-day lead time to prepare.
AR4491, the sunspot region that drew flare attention last week, has stayed small and quiet so far, while an unnumbered northeast-limb region producing C-class flares remains a secondary wildcard.