A somewhat stalled and blocked weather pattern will continue to funnel gulf moisture northward into the Midwest and Great Lakes these next few days, with us really seeing an increase Monday afternoon. High pressure pushing well into the Pacific Northwest will bring triple digit heat up and down the West Coast this week where several record high temperatures are likely to fall. Downstream, low pressure remains anchored over the Plains and Midwest thanks to a blocking high pressure over the Southeast.
The high to our southeast and low to our northwest will keep the moisture in place as a stalled out frontal boundary wobbles back and forth (north and south) under southwest flow aloft. That boundary Sunday was far enough to the south to keep storm chances well downstate. But we could see an increase in some of those rain showers late Sunday night as the boundary is slowly pulled back north with an approaching low pressure system. Overall coverage is expected to remain light, but a few light showers could be ongoing early Monday morning.
Showers and thunderstorms will then become likely Monday afternoon with the heating of the day and the frontal boundary close by. While a few of the stronger storms could produce some gusty winds, our biggest threat appears to be torrential downpours as copious amounts of moisture will be present in the atmosphere. It won’t be like the widespread heavy rain we experienced last Sunday evening with the severe weather, but more scattered, meaning some areas could see half an inch to three quarters of an inch while others don’t get much at all. And while a few showers are possible Monday evening, we’ll see our rain chance increase again Tuesday afternoon. Between the next few days it’s possible for another one to two inches of rain to fall.
A cold front will move through Wednesday and Thursday as the upper level trough currently over the Plains begins to east thanks to the high over the southeast weakening. Showers and thunderstorms will continue to be a threat Thursday, with a few showers possible Friday afternoon. The chance for rain heading into the holiday weekend, right now, appears to be low. If the low is slow to move Friday and Saturday then showers will last into the start of the weekend and temperatures will be cooler. If, however, the low is quick to move (which it looks like will be the case) then the majority of the weekend will be dry with highs warming back into the upper 70s and low 80s.