Mesoscale Discussion #2236: Michigan

SPC issues Mesoscale Discussion #2236 for heavy snow:

A dominant and well-organized lake-effect snow band remains firmly in place early this afternoon across northern Lower Michigan, supported by a notable upstream connection to Lake Superior. Dual-pol imagery from KAPX continues to sample elevated KDP values within the core of this band, indicating highly efficient snowfall production. As a result, snowfall rates on the order of 1 to 2 inches per hour remain likely in the most persistent portions of the band.

Given the lack of significant change in the synoptic environment through the next several hours—particularly the steady low-level wind field and continued cold air advection over the lakes—there is strong confidence that this band will hold its current structure and intensity well into the afternoon. High-resolution ensemble guidance supports this scenario, showing a sustained and narrowly focused plume of enhanced reflectivity lingering over roughly the same corridor.

As we move toward late afternoon, the most intense snowfall rates are expected to gradually diminish. This weakening will coincide with the departure of mid-level ascent associated with an exiting shortwave trough, which has been providing an additional boost to vertical motion and crystal growth. With this support fading, subtle adjustments in the wind field between 850 and 700 mb—shifting slightly more northerly—may also induce a minor southward drift or wobble of the band.

Nonetheless, conditions will remain favorable for continued accumulation through the early evening, and localized heavy totals remain possible wherever the band lingers longest. Visibility will also remain periodically reduced, especially in rural and open areas, making travel hazardous in the core of the snow band.