Monday Afternoon Discussion

The cold front has pushed completely south of the area, and the results have been spectacular weather for July. Dewpoints in the mid 50s (very dry for this time of year) and light northerly winds have made for a beautiful and low humidity day. But enough about now, what about the week ahead?

Essentially the weather will be the same. Sunny, dry, and gradually warming up.


The 12z GFS model run showing 2m temps and surfaces winds valid at 1 am Wednesday morning shows high pressure over the Ozarks, giving us clear skies and still relatively dry air. Bertha continues to meander through the Atlantic, pestering Bermuda with high surf and occasional rain squalls. The main precipitation area will be confined to Florida (sea breeze thunderstorms) and the Upper Midwest/Plains (where the jet stream is). Bertha will wander around before finally pulling north-northeast and away from Bermuda.

Looking into the GFS crystal ball:


This is the 500mb chart of the 12z GFS valid at 7 pm Tuesday, July 29. A trough is centered across the East and Northeast. That X centered near Sikeston ad the MO/IN/KY border is an impulse of energy riding the flow aloft. If we look at the surface features...


We see a typical summertime pattern with scattered thunderstorms across the Southeast, with the disturbance aloft enhancing rains in the afternoon hours. At the surface, the general flow will be from the south, so moisture would certainly be in place. For us, we would be on the back side of the trough, limiting our rain chances. But again, with the flow at the surface coming out of the tropics (see all those winds from the Atlantic/Gulf moving west and then north?), we can expect the summertime storms in the afternoon hours.

Tomorrow, weather across "The Pond" as the British Open starts Thursday.

Early Evening Radar

Saturday Afternoon Map Discussion

The two H's have dominated the weather here in the Mid-South lately. HOT and HUMID. Dewpoints in the low to mid 70s are putting the heat index in the 100-105 range for today. Having been outside today, I can tell you it is definitely humid. That humidity will lead to rainfall as we head overnight and into tomorrow.



Above is the 12z NAM model valid at 10am, and it clearly shows the cold front moving through the region. Expect some heavy rainfall out of this frontal passage - on the order of one half to one and a half inches. Much drier air will push into the area, and overnight lows at the beginning of the week may dip down into the upper 50s in some locations. The humidity will slowly creep back up throughout the week, so the air will feel more and more sticky as the week goes on.

That's all for now. Crystal ball discussion later.

Wednesday Afternoon Radar and Map Discussion

Let's first take a look at the radar at 3:56 CDT:

Let's take a look at the weather for tomorrow, courtesy the 12z NAM model run valud at 1 pm Thursday afternoon:

I've drawn in three items of note. First, the monsoon season is underway across the desert Southwest. That's evident with the surge of moisture. The cold front producing activity here today will continue to sag through the area tomorrow, keeping rain chances in the forecast. A second front is taking shape across the Midwest. That will move in over the weekend. With the old front hanging around and the new front set to move in, expect scattered to isolated thunderstorms the remainder of the week.

That's all for now. More later.

Summer Storms and Outflow Boundaries at Work

Check out the two radar images below (courtesy Wunderground):


Now look at the radar 8 minutes later:


Notice how quickly the storms in Fayette County grew along that outflow boundary.

More information on outflow boundaries can be found here.

Model discussion tomorrow.