27ºF

Heat, humidity and storm chances will stick around in metro Detroit

Plus, a severe storm threat to discuss for Wednesday

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DETROIT – Lots to chat about today, so let's get right down to it:

Steamy conditions this afternoon have promoted a few isolated pop-up showers across our area. Most of us didn't see any rain, but the threat for a shower or thunderstorm remains with us well into the evening. Later tonight, as things stabilize with some cooling, I think the activity will settle down. Lows only dropping to around 70° (21° Celsius) -- another muggy, sticky, difficult night for those without air conditioning. Wind overnight should remain very light.

Tuesday forecast:

We'll likely start our Tuesday with a lot of cloud cover, but skies should eventually become partly cloudy. As the sun comes out, we'll bake once again (although not quite as hot as today), with steamy highs in the low to mid 80s (28° Celsius). South-southeast wind at 5 to 10 mph. A few isolated thunderstorms are possible during the mid-to-late afternoon period but, like today, many of us won't see a drop. Still, if you have outdoor plans, stay alert and monitor the radar on our FREE Local4Casters app. Also remember to follow me on Twitter, as I tweet weather updates and radar images whenever the weather takes a turn. Tuesday's sunrise is at 6:44 AM, and Tuesday's sunset is at 8:30 PM.

There's a small chance of thunderstorms Tuesday night, with lows once again near 70°.

Wednesday forecast:

Wednesday is the day that's been in my crosshairs since last Friday. A strong cold front will approach late in the day, with a line of storms developing ahead of it. We'll still be in the steamy air mass, and it's possible that we can even get some sunshine during the first half of the day, which would boost our temperatures into the mid 80s and create an unstable atmosphere. Other ingredients I'm watching is a strong jet stream aloft to our west. Ahead of that, wind aloft will tend to diverge and, when diverging wind aloft overspreads a very unstable air mass, then widespread severe storms are more likely.

However, this Wednesday is not a slam dunk situation -- some of the crucial ingredients I watch are still uncertain in terms of timing and placement. Furthermore, there are other factors that can come into play. For example, let's say a batch of "innocent" storms develops well ahead of the front and crosses our area during the morning -- this could work over and stabilize our atmosphere and reduce our thunderstorm severity later on. Or, let's say that the divergence aloft I mentioned earlier lags behind and doesn't coincide with the storms along the surface front -- then our storm intensity would be impacted. There are a lot of details to still work out (including a lot more I don't have time to discuss here). Tomorrow's models, and then Wednesday morning's new upper air data from the radiosondes (weather balloons) will provide a lot more detail and, naturally, I'll keep you updated.

And while we're on the subject, I realize that a lot of people are interested in the weather, and love to see severe weather (be careful what you wish for). One person, in fact, asked me about the potential "tornado outbreak" on Wednesday. Yes, there's a lot of weather information available on the internet. However, this past weekend, people started tweeting me (yes, I respond to most tweets as long as I'm able to) asking about the Storm Prediction Center putting us in an initial long-range severe weather outlook for this Wednesday. Please understand that these long-range outlooks are just that: outlooks. I discussed above some of the meteorological details I need to monitor, and I cannot possibly predict the precise nature of those details five days in advance. This is why I have mixed feelings about this type of information being available to the public. Yes, some of you want to feel empowered, and want to have the ability to find and see this information yourself, but when people start tweeting me about severe weather five days in advance, other people not as weather savvy are hearing about this for the first time and, given the sensationalistic nature of social media, then get the wrong idea -- and this is very harmful.

Alright, I digressed. Sorry about that. The storms that develop late Wednesday will continue into Wednesday night. Lows in the low 60s, as long as the front clears the area by 3:00 AM.

Thursday forecast:

Partly cloudy on Thursday, with only the slight chance for an isolated mid-to-late afternoon shower. Cooler and less humid, with highs in the mid 70s.

Mostly clear Thursday night, with lows in the upper 50s.

Mostly sunny both Friday and Saturday, with highs approaching 80° on Friday, and into the low to mid 80s on Saturday, with overnight lows in the low to mid 60s.

I'm hoping to salvage Sunday. Another cold front should cross the area Sunday night, but the models differ just enough on the timing to make it uncertain whether storms will hold off until Sunday night, or if they'll develop in the late afternoon. I'll keep a close eye on the models and keep you updated. Regardless of the front's timing, highs should reach the mid 80s.

Remember, when it comes to weekends, I'm a professional. The weekend is always on my mind -- I'll be watching this closely.