Kristen M. Daum and Mike Nowatzki, Forum staff writers, Published August 14 2010
Storms, warnings plentiful in region
Blame it on Mother Nature’s perfect mix of geography, atmospheric conditions and a climate pattern that’s spicing things up.
As of Wednesday, eastern North Dakota and northwest Minnesota had seen 158 severe thunderstorm warnings and 115 tornado warnings so far in 2010, said Jim Kaiser, a National Weather Service meteorologist in Grand Forks.
In all of 2009 – when the weather was cool and much calmer – 52 severe thunderstorm warnings and 53 tornado warnings were issued, Kaiser said.
The northern Plains are experiencing the final stages of an El Niño that began last fall, the weather service said.
An El Niño means there are warmer-than-normal sea-surface temperatures in the tropical Pacific Ocean, which can impact global weather patterns.
El Niños tend to cause severe weather in the southern and eastern United States during winter and spring, but as summer approaches, a souped-up jet stream moves northward bringing with it the potential for worse severe weather.
Combining that energy with southern winds that drive in low-level moisture instigates more intense weather than the Red River Valley might typically see, Kaiser said.
“With the moisture in place and a stronger jet stream, you’re able to make your thunderstorms stronger,” Kaiser said.
By late July, the Grand Forks office had issued more tornado and severe weather warnings than it had in the past two years.
“The fact that we’ve had this many, the pattern shows that it’s probably associated with El Niño,” Kaiser said, but he added: “In years when you don’t have El Niños, you still have (severe weather), so it’s really a question of: Is it induced by this or just a product that we would’ve had anyway?”
The latest blitz of severe weather came through the region late Thursday and early Friday. Thunderstorms carried heavy rains and strong winds that caused street flooding and power outages in Fargo-Moorhead and possibly spawned a tornado in southeast North Dakota near Geneseo.
Whipping winds knocked down tree limbs that fell onto power lines, which sparked a fire in at least one case in north Fargo.
About 4,100 Xcel Energy customers in south Fargo lost power at 10:10 p.m. Thursday for about 90 minutes, spokeswoman Bonnie Lund said. The outage affected an area from Interstate 94 to 32nd Avenue South and from I-29 to the Red River.
At the height of the storm, an additional 1,000 customers also were without power, Lund said.
Xcel was still working to restore power to seven customers as of Friday afternoon, with the goal of restoring service to them by Friday night.
Readers can reach Forum reporters Kristen Daum at (701) 241-5541 and Mike Nowatzki at (701) 241-5528