A Heat Advisory will be in effect from noon tomorrow (Wed.) until 2 am Thursday. The Advisory is for Ottawa, Kent, Allegan, Barry, Van Buren, Kalamazoo, Calhoun, Berrien and Cass Counties. Heat Advisories and possible Warnings will also be in effect for N. Indiana, N. Illinois and W. Ohio.
The Heat Index is expected to climb to near 100. Heat Advisories and Warnings will likely be in effect again on Thursday. These two days could be the warmest days we’ll see this summer. The GFS model gives Grand Rapids high temperatures of 94 on Wed. and 93 on Thu.
There are quite a few high school football games scheduled Thursday evening. For the fans in the stands and especially for the players, it’s important to stay hydrated. The sun will be lower in the sky by gametime, but find some shade if you can.
The Storm Prediction Center has a Marginal Risk of a severe thunderstorm late tonight and early tomorrow for areas generally east of US 131. SPC says:
A mid-level anticyclone will be located across the central U.S. today. On the northeastern periphery of this feature, mid-level flow will be from the west and northwest across the Great Lakes region. Thunderstorms will likely be ongoing across parts of Lower Michigan at the start of the period. This activity is expected to weaken by late morning. A moist airmass will advect eastward across Lower Michigan today, with surface dewpoints increasing into the lower to mid 70s F. Within northwest mid-level flow, a shortwave trough is forecast to move southeast across the eastern Great Lakes. Ahead of this feature, model forecasts consistently develop scattered thunderstorms late this evening. This activity is forecast to organize into an MCS and move southeastward across eastern Lower Michigan, and into northern Ohio and northwest Pennsylvania during the overnight period. RAP forecast soundings near the track of the MCS around midnight suggest that the storms will be surface-based with strong instability (MUCAPE above 4000 J/kg), and moderate deep-layer shear. This should support a wind-damage threat as the MCS develops into a bowing line segment.
Small Craft Advisories will be in effect tomorrow (Wed.) from Ottawa County to the north. This includes Grand Haven State Park, where dangerous currents may develop on the south side of the pier. Waves will likely be in the 2-4 foot rangeA Beach Hazards Statement will likely be issued for Wed. (and possibly on Thu.). Do not swim near or jump off the piers and on breezy/windy days.
We also have an Air Quality Alert for Wed. and Thu. The Air Quality Index will likely reach into the Unhealthy category both days.