Metro Detroit weather: Honing in on how much rain to expect this weekend

Showers, thunderstorms in the forecast

DETROIT – The upper level low pressure area we talked about yesterday is slowly drifting into Indiana but, as it weakens, will pick up the pace and start heading northeast right toward us overnight into the first half of our Saturday.  

Bands of showers and possible thunderstorms rotating around the upper low will cross the area this evening, but there will be dry periods in between. The humidity is coming up, too, so overnight lows should hold in the mid 60s (18 degrees Celsius). The east-northeast wind we’ve had today will continue the lakeshore issues along Lake Erie into this evening, which developed due to that wind plus the already well above average water levels. A Lakeshore Flood Warning is in effect until 10:00 p.m. for the Lake Erie shoreline in Monroe County, and a Lakeshore Flood Advisory is in effect until 10:00 p.m. for the Lake Erie shoreline in Wayne County.

Saturday will be one of those days where our free Local4Casters app will come in very handy if you have outdoor plans. Here’s how we see the day shaping up: scattered showers and thunderstorms will start our day, with a period of less activity for the late morning / early afternoon hours. However, any peeks of sun we get in the afternoon will pop-up more scattered showers and thunderstorms.  It is important to remember that that the activity will be scattered: not everybody will be getting rain at any particular time on Saturday…there will be parts of the day that are dry.  

That’s why you should check the customizable radar on our app if you are trying to find a time to get outside…perhaps a short walk with the dog, a bit of yard work you need to do, etc.  As long as we get a bit of sun, highs should reach the upper 70s to near 80 degrees (26 to 27 degrees Celsius).  A light and variable wind will eventually blow from the southwest at 5 to 10 mph.

Scattered showers and thunderstorms will gradually diminish Saturday night with the loss of the daytime heating. Temperatures by dawn will be in the mid-60s (18 degrees Celsius).

Sunday could potentially start dry at dawn, but scattered showers and thunderstorms my pop-up in the morning, with a better chance during the afternoon as a cold front slides by. Again, our app’s radar will be a very valuable tool if you need to find a dry period on Sunday. Expect highs in the mid 70s (24 to 25 degrees Celsius).

Rain will finally end Sunday night, with lows back down into the mid to upper 50s (14 to 15 degrees Celsius)…much more comfortable sleeping weather.

Monday is the big Ford Fireworks show, and the weather continues to look perfect, with mostly sunny skies during the day for those of you coming downtown early to stake out a good spot to watch.

Don’t forget the sunscreen…the sun’s rays right now are at their most powerful of any time of the year. Highs in the upper 70s (26 degrees Celsius) will cool through the 70s during the evening, and perhaps into the upper 60s (20 degrees Celsius) by 11:00 p.m. Combine this with very light wind (or none at all), and we have spectacular weather for North America’s biggest fireworks show. Of course, if you can’t make it downtown, Local 4 is your exclusive station…the ONLY station to bring you live coverage from start to finish. Tune in starting at 8 p.m. for all of the fun and excitement!

Clear skies Monday night, with lows again in the mid to upper 50s (14 to 15 degrees Celsius).

Mostly sunny to start on Tuesday, then we may see some increase in cloud cover during the afternoon. Some models keep the day dry, but one model (the GFS) tries to bring in some showers and thunderstorms by the end of the afternoon. The GFS has a tendency to sometimes move weather systems along too fast so, right now, we’ll side with the other models and go for a dry daytime. As long as we hold off the rain, highs should reach the low to mid 80s (28 to 29 degrees Celsius).

Showers and thunderstorms are likely Tuesday night, and it becomes muggy, with lows near 70 degrees (21 degrees Celsius).

Expect showers and thunderstorms Wednesday morning, then ending from west to east during the afternoon. Highs in the mid 80s (30 degrees Celsius).

Partly cloudy, hot and humid on Thursday, with highs near 90 degrees (32 degrees Celsius).

This starts a hot and humid stretch that now appears to extend all the way through next weekend, with highs near or a little above 90 degrees (32 to 33 degrees Celsius), and overnight lows in the low 70s (22 degrees Celsius).  

It’s too difficult to try and time any particular thunderstorm chance, so stay tuned on that.  But it’ll be another stretch where those of you without air conditioning at home will really suffer.