Weather Alerts For Rochester, MI

There is a Marginal Severe Storm Risk for your location. Continue reading for today's outlook from the National Weather Service's Storm Prediction Center. -------------------- National Severe Storm Outlook THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS FROM THE NORTHERN/CENTRAL PLAINS TO THE LOWER OHIO VALLEY SUMMARY Scattered severe thunderstorms are possible today through this evening from parts of the mid Mississippi Valley and lower Ohio Valley into portions of the central and northern High Plains. Severe gusts and large hail are the primary hazards. IA to OH Valley Radar/satellite imagery this morning show several thunderstorm clusters ongoing from IA into the OH Valley. The most notable thunderstorm cluster is over far eastern IA and is moving into central and northern IL this morning. The airmass downstream of this activity is very moist and extremely unstable [reference the 12 UTC Davenport, IA raob (4300 J/kg MLCAPE)], and it is located near the terminus of a 35-kt west-southwesterly LLJ over northern MO. Expecting a gradual intensification of storms this morning across IL with a risk for scattered severe gusts and associated wind damage. Considerable uncertainty remains regarding the eventual evolution of additional storm clusters over parts of the Midwest through this afternoon. Outflow from morning showers/storms over eastern IN into central KY will likely inhibit appreciable severe risk farther east across parts of the OH Valley. Nonetheless, a moist and destabilizing boundary layer will lend a risk for scattered wind damage and isolated large hail with the stronger storms through the late afternoon and evening. Northern/Central Plains East/southeasterly low-level flow will maintain modest moisture across the Dakotas, increasing with southward extent across NE into northern KS. Near-60 F dewpoints will likely spread westward into eastern CO/WY/MT beneath steep lapse rates. Ample heating will result in moderate buoyancy and 30+ kt effective shear---supporting some organization to the scattered thunderstorms forecast to develop later this afternoon/evening. Initial cells will pose a threat for large hail and severe gusts. Some clustering may occur during the evening but confidence remains low regarding specific corridors where the severe threat will focus. Lower MI into NY/PA/NJ A belt of stronger northwesterly flow aloft will extend from Lower MI into NY/PA today. A seasonally moist/unstable airmass will be in place. Vertically veering wind profiles will foster 35+ kt effective shear magnitudes, while hodographs are fairly elongated. Midlevel lapse rates will remain modest, with MLCAPE around 1000-1500 J/kg expected. Isolated to widely scattered storms will pose a risk for damaging gusts and marginally severe hail. TN Valley/Southeast Thunderstorms are expected to develop by midday within a very moist and strongly unstable airmass. Deep-layer northwesterly flow will remain weak, but steepened 0-2 km lapse rates and high PW (near 2 inches) will support an isolated risk for some stronger water-loaded downdrafts capable of wind damage. Lower CO River Valley Model guidance shows widely scattered storms developing this afternoon near a weak upper trough analyzed this morning via water-vapor imagery. Some of the stronger thunderstorm downdrafts may be capable of isolated severe gusts.

Pollen Index: 8.6 Pollen Level: medium-high Predominant Pollen: Grass, Nettle and Plantain. The amount of pollen in the air for Thursday will be on the increase in the high range. This higher level is caused in part by higher temperatures and the lower dewpoint.