Today’s forecast is one of those in which the overview is easy, but the specifics are very challenging. So…let’s start with the easy part: it will be hot, it will be very muggy, and scattered storms are possible.
Not so fast. Let’s take a shot at some specifics. Before sunrise this morning, a complex of thunderstorms moved straight south from Missouri into Arkansas. That trajectory keeps those specific thunderstorms from impacting us here in the Midstate, but the rain-cooled air from those storms doesn’t go just to the south — it spreads out to the east and west as well:
As that rain-cooled air advances, it pushes on the lowest levels of the atmosphere, which forces some of the air upward (think of pushing a tablecloth, and the folds that develop). That allows thunderstorms to develop in advance of the cold air, which is what we’re seeing along the Mississippi River as I type this (8:30am-ish).
So, how will those storms behave once they’ve matured (the arrow should give you a hint)?
Figuring that out is made more complicated by the fact that the forecast model data for about the last two weeks has been, well…
…yeah, that pretty much sums it up. The forecast models have been all over the place, whether you’re comparing different models, or even different runs of the same model. So we have to take our precious computer data with a giant grain of salt.
The RPM model brings storms from west-to-east across the Midstate from late morning through early afternoon, with the storms weakening as they progress:
The HRRR model is a little faster, but more “robust” — it produces more widespread and stronger storms.
But the WRF model thinks the morning storms will head off to the southeast, and we’ll have to wait until this afternoon for storms to pop up directly overhead or move in from the west.
Right now I lean bit more toward a midday-through-afternoon compromise — that is, I buy the RPM timing, with the HRRR strength…I’m not sure what the WRF is doing. (It won’t rain the entire time I indicate on this map — these are the “storm windows” when the strongest storms are most likely):
That means we’ll have plenty of time for temperatures to heat up (notice the rain-cooled air, though…):
And it will feel…gross.
The Storm Prediction Center has outlined a “Slight Risk” (level 2 of 5) for severe thunderstorms, which means that we’ll see numerous thunderstorms, a few of which could produce damaging straight-line wind gusts:
Plan on staying-weather aware this afternoon.
Tomorrow brings more of the same, but it won’t be quite as hot. I expect thunderstorms to develop directly overhead, instead of moving in from elsewhere, and once again a few of them could be strong-to-severe. The complicating factor here is that today’s storms could re-arrange the atmosphere and alter tomorrow’s storm chances significantly:
- A massive heat wave will grip the middle of the country next week (we’ll feel the influence more directly around here by Thursday and Friday).
- We had significant flooding problems around here last week — this week, it’s been happening in Minnesota and Wisconsin.
- The National Weather Service suffered a “major network disruption” yesterday, and even the warning system was compromised.
- The percentage of Americans who are concerned enough about climate change to allow it to influence their vote it rising.
- One of the titans of the severe thunderstorm research community (an absolute legend) weighed in on the supposed “debate” over climate change.
- NASA released another “moon photobomb” image — but why does it look so fake?
- A 3-D printer on the International Space Station is being tested to create parts that otherwise would have to be sent to space on a rocket.
- Astronomers have captured their first glimpse of the “snow line” forming around a new-born star.
- Could gravitational waves be used to make images of planets in other solar systems?
- As asteroid/comet impact helped bring an end to the era of the dinosaurs…but did an asteroid impact help start that era?
- Effective antibiotics allow us to take for granted elective surgery, chemotherapy, and organ transplants…but the rise of antibiotic-resistant bacteria may put an end to that.