Scattered Severe Weather Possible Today - Saturday, July 19th, 2025

Summary:

Scattered severe weather continues to remain possible today, with the SPC outlining a broad level 2/5 Slight Risk across much of the area. Damaging winds and heavy rainfall are the primary threats, with an isolated tornado or 2 and locally large hail as lower threats.

Discussion:

A difficult forecast is once again the theme for today's severe weather risk across West Michigan. A more robust line comprised of clusters of storms and bowing damaging wind segmenets is possible after the noon hour across the area. However, there are several variables that all need to come together for these storms to actually pose a severe risk across the area.

Areas along and south of the I-96 corridor have the best chance of seeing severe thunderstorms today. A couple of storng storms may occur farther north, perhaps as far north as Traverse City, but the threat for a bonified severe storm is lower in this area, and small hail and gusty winds are much more likely. If severe storms do occur, the best chance will be sometime between noon and 9:00 PM, with the early to middle part of the afternoon the most favored time frame.

Severe storms are definetly not a guarantee, though with plenty of very realistic forecast scenarios resulting in little to no severe weather threat today.

• Thunderstorms need to develop this afternoon out ahead of the cold front as they move into an environment here that is more stable (less favorable for development) than on the other side of Lake Michigan.

• Storms also need to have a trajectory that moves them into our area. It is totally possible that an atmospheric effect known as gravity wave action, which is ongoing to our South, may pull storms like a magnet into that area instead of having them move through our area in a west to east fashion.

• Early morning cloud cover and isolated rain showers may just prove to be too inhibiting to the development of a favorable severe storm environment.

Timing:

As aforementioned, if severe storms do indeed develop or move into the area, the most likely time for this to occur will be in the early to mid-afternoon, with the threat generally winding down for our entire area by 9:00 PM at the latest. Storms will first impact the US-31 corridor near I-96 and move eastward towards US-131 and US-127 as the afternoon continues, reaching those areas by 4:00 PM and 6:00 PM, respectively. Additional storm development is possible along US-10 by 7:00 PM this evening, and this will also track east/southeast though the severe threat will, once again, be lower in this area. This is also the more favorable timeframe for storms near I-94, though it is unclear how strong these storms will be. Bottom line, the best shot at severe storms will be this afternoon with the initial cluster of storms as it tracks along and near the I-96 corridor from west to east.

Marginal - Slight Risk:

As we stated in the forecast summary above, the NWS Storm Prediction Center has outlined a broad level 2/5 Slight Risk for severe weather for areas south of US-10 with a narrow level 1/5 Marginal Risk in place for areas along and north of US-10.

Remember, a Slight Risk means that scattered severe storms are possible and that an isolated significant severe storm is possible. Today, this slight risk is driven by a 15-29% chance for damaging wind gusts, but an isolated tornado or local large hail event is also possible.

Tornado Outlook:

The risk for a tornado today is not particularly high, but it also not zero. An isolated, brief, and weak spin-up style tornado or 2 are certainly not out of the realm of possibilities today, given modestly favorable low-level SRH (storm spin) and slightly curved wind profiles in the lower levels of the atmosphere near the surface. The best chance for a brief tornado or 2 will be near I-96, probably between Grand Rapids and Lansing, particularly where any small-scale local features like a lake-breeze boundary, outflow boundary, or storm mergers occur.

Damaging Wind Outlook:

As mentioned above, today's Slight Risk is driven by a 15-29% chance for at least 1 damaging wind gust within 25 miles of a given point in areas south of US-10. Scattered gusts in this area could range from 50-70 MPH.

Large Hail Outlook:

The threat for large hail is the least concerning for today, thanks to overall unfavorable atmospheric conditions for the development of robust updrafts that could force rain into the freezing layer. The best chance for hail will be with any thunderstorm activity closer to US-10. However, I think any hail that does fall in this area will likely be sub-severe (under 1 inch in diameter), once again owed to the generally unfavorable conditions for hail growth. Still, a locally severe hail stone or 2 can't be entiely ruled out with any thunderstorm today, especially in this area.

Conclusion:

The bottom line is that this is yet another tricky forecast setup across the area today and it may wind up being just a cloudy summer day with a few thunderstorms possible, however, it could just as easily be the next notable severe event of this year with the possibility of scattered to more widespread wind damage and perhaps a tornado or 2 across the area so we need to continue to monitor the weather today. Have multiple ways to receive watches and warnings and heed the advice of the NWS and local officials if a warning is issued for your area.