Beau Dodson's WeatherTalk Blog

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It has certainly been a difficult week of forecasting.  The primary uncertainty each day has centered on rain probabilities.  How high and how low to place the percent number.

I knew it would rain each day, but trying to put a % number on it has been difficult.

Most of the region experienced showers and thunderstorms over the last few days.  Some locations have received 1 to 3 inches of rain.  Some places have received less than 0.10″ of rain.

The next 48 hours will bring more of the same.

I lowered today’s rain probabilities.  There will be precipitation on radar today, but many areas may end up dry or mostly dry.

Twenty-four hours ago, today looked like it was going to be quite wet.

Last night’s storms stabilized the atmosphere.  I only expect widely scattered showers and thunderstorms today and tonight.

Then, I expect rain coverage to increase tomorrow and tomorrow night.

A few of the thunderstorms could be intense over our eastern counties today and tonight.  Then, across a bit more of the area on Friday.

Overall, the threat of severe weather will remain minimal.

Today’s severe weather outlook.  Light green is where storms are possible, but below severe levels.  Dark green is a level one threat zone.  The lowest threat.  Yellow is a level two (slight) risk.

Today’s outlook

Tomorrow’s outlook

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Rain totals will vary greatly based on the placement of thunderstorms.  Storms can always enhance rain totals.

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A few showers may linger into Saturday and Saturday night.  The chances will be a bit higher over Kentucky and Tennessee on Saturday.

Rain chances on Sunday will be low, but perhaps not zero over our eastern counties.  Any rain would be light.

A big upper-level low will push into the region this weekend.  That will bring cooler air.

You can see that upper-level low on this 500 MB vort max from the GFS model.

It will turn quite a bit cooler on Saturday and Sunday.  Highs will mostly be in the 60s.  Lows this weekend will be in the 40s and 50s.  A bit of a chill in the air.

Check out these temperature anomaly maps.  These maps show you how many degrees above or below average temperatures will be.

Above average today (orange and red).

Check out tomorrow into Monday.  Blue, green, and purple colors.  That represents below-average temperatures.

Sunday

Monday temperature anomaly map

Peak tornado season is May.  Any time we have cooler air in May, it is a good thing.  It does help keep the tornadoes away.

I continue to worry about a severe drought this summer over portions of the central United States.  Perhaps centered on Iowa.

The question may be our region.  Will we slip into drought, or will we remain in the MCS train-zone?  MCS’s are large summer thunderstorm clusters that ride the heat ridge.  Up and over the drought zone.  They can bring heavy rain and severe weather.

I am monitoring trends in the guidance.

Let’s take a look at the latest rain probability maps for the next couple of days.

Double-click each image to enlarge it.

Today’s rain probabilities

You can expect 20 to 30% chances area-wide.  Scattered thunderstorms will be possible.

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Tonight’s rain probabilities

Similar tonight.  Scattered showers and thunderstorms.

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Friday’s rain probabilities

Chances on Friday may end up higher over far southeast Missouri, far southern Illinois, Kentucky, and Tenenssee.

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Friday night’s rain probabilities

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Saturday’s rain probabilities

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Saturday night’s rain probabilities

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Sunday’s rain probabilities

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A warming trend is expected to return around the middle of next week.
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Let’s look at some future-cast radars.

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Double-click the animation to enlarge it.

Hrrr model.  This shows you the shower and thunderstorm activity today into tomorrow.

As you can see, periods of showers and thunderstorms.

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Here is the NAM model.

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