Why Are There “Gales of November?”
Is it true that November spawns more high-energy storms than other months of the year?
“November is what we call a transitional month,”
says Carol Christenson, warning coordination meteorologist at the
National Weather Service in Duluth, Minnesota.
The transition from a warmer to a colder season
agitates stronger high and low pressure systems, creating the clash
between what comes up from the southwest and what comes down from the
northeast. Those resulting gales can hit or surpass 75 mph “hurricane”
winds. Also, as we head into winter, the jet stream - benignly north
most of the summer - dips south more frequently to rile up Rocky
Mountain storms to send our way. Prevailing winds on Lake Superior are
from the east March through August, then from the northwest September
through April.
Finally, November - and April - are storm prone because, unlike the middle of winter, more water is open, Carol says.
Lake Notes
 This
summer brought rumors of tiny clear jelly-like globs showing up on
beaches all around Lake Superior (made the front page in theDuluth News Tribune). Turns out the stories were a lot of Holopedium gibberum
- the name of the zooplankton that discarded these protective gel
globes as part of its life cycle. While periodic appearances of these
clear “balls” are not unusual, Minnesota Sea Grant did report in
October 2005 that the invasive spiny waterflea may have caused a
decline in native species Bosmina longirostris and Daphnia retrocurva but an increase in Holopedium gibberum.
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