Significant risk for severe thunderstorms through this evening from east-central Minnesota into north-central Wisconsin

Today’s severe weather setup is a potent one with Moderate and Enhanced risks for severe thunderstorms in place through this evening in southern portions of the Northland.

Moderate risks do happen in this area, but not very often, maybe once or twice a year.

Severe weather risk is based on a 5 point scale with 1 being the lowest risk (marginal) and 5 the highest risk, so today’s risk is sitting in the 3 to 4 range across southern portions of the Northland, that’s a significant risk!…

If you live in the severe weather risk zone, here’s what you can do to prepare…

Don’t cancel any plans you may have, but be aware that weather conditions could change rapidly later this afternoon. Make sure you know what County you live in, and the part of the County you live in in case a watch or warning is issued later today. Be prepared! Have an emergency kit ready to go just in case severe weather and damage occurs in your area. Take shelter immediately if a warning is issued!

…Impacts…

  • Risk to life and property.
  • Severe damage to trees, buildings and power grids.

Difference between a watch and warning

A watch means that conditions are favorable for the development of severe weather in and close to the watch area, typically a watch is in effect for 6 to 8 hours, and a watch doesn’t guarantee that your specific location will see severe weather or damage, it just means conditions are favorable for the development of severe thunderstorms while the watch is in effect.

A warning means severe weather is occurring or is imminent.

Today’s severe risks range from marginal to moderate across the Northland — Here’s what these risks mean.

One of the reasons for the potential severe weather outbreak later today is due to the strong winds in the mid/upper levels of the atmosphere, this is a little unusual to see such strong jet stream winds in mid July.

We already have a large pool of extreme CAPE (instability) in place across southern Minnesota, this will advect slowly north/east through this evening as low pressure lifts east-northeast out of eastern South Dakota.

Just an incredible amount of moisture in place today with widespread 70 to 80 degree dew points across the southern half of Minnesota.

Severe weather has already been occurring late this morning-early this afternoon over a small portion of western Minnesota (red outlined area on map)

Here are two radar forecasts from two different models showing how things could play out through this evening.

Radar forecasts are from 1 PM to 10 PM Friday.

Note: Trying to time when these storms develop or impact parts of the Northland is always tough, but there seems to be some model consensus between a 3-10 PM time frame for when storms and possible severe weather could impact southern areas of the Northland.

First model is the NAM-WRF (12z run)

Next model is the HRRR (16z or 11 AM run)

In closing this has the potential to be a big severe weather day in southern portions of the Northland, we don’t see a setup like this very often. A combination of supercells capable of producing very large hail, tornadoes and damaging winds along with a possible bow echo (derecho) which could go on to produce widespread significant wind damage is possible later today in parts of east-central Minnesota into north-central Wisconsin.

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