Needed rain is coming

It's been an interesting last few days in terms of temperature at Flint's Bishop Airport.

I'm often impressed at how cold it can get there at night compared to surrounding communities when skies are clear and winds are light, and then warm up just as much as everyone else in the afternoon.

But every day since Tuesday has had a very cool start followed by a very warm afternoon giving us a wide diurnal range in temperature.

The diurnal range in temperature -- the difference between the morning low and afternoon high -- from Tuesday through today has been 35°, 37°, 41°, and 37° respectively in Flint.

Our average high and low this time of year in Flint is 68° and 45°, giving us an average diurnal range of 23°.

So I asked myself on my way home from work last night, what could be causing this wide difference between day and night?

It quickly hit me that it hasn't rained in awhile, and the dry soil must be allowing us to warm-up quickly after our chilly morning lows.

So I did a little research today and found that it hasn't rained in Flint since September 16th (image 2), and our rainfall deficit for the month of September is almost 3" (image 1)!

Similar stats can be found for Saginaw's MBS Airport, showing it's been an unusually dry September there as well.

However, the 0.19" of rain that fell there on the 20th must have left enough moisture in the soil there to prevent the almost desert-like diurnal range in temperature that Flint has been experiencing.

The biggest diurnal range in this same stretch for Saginaw was 35°, and this occured today with a low of 44° and a high of 79°.

Having said all of this, we're still in decent shape in terms of drought.

The Climate Prediction Center (CPC) lists sections of western and northern Lower Michigan as abnormally dry, but the southestern quadrant of the state isn't analyzed in the CPC's Drought Monitor (image 3).

That's mainly because we're still running about 2" above normal for the year, thanks to a wet spring and early summer.

Still, to help keep us out of drought status, any rain we get on Sunday will be welcome.

For the week ahead, dry weather will resume through Wednesday, followed by another opportunity for rain Thursday and Friday as a strong area of low pressure moves across the Great Lakes.

Click on the video for your complete forecast.