Wednesday August 1 Update

3PM Update:

Severe Thunderstorm Watch issued until 10PM for parts of west KY:

Storms have been firing along a weak convergence boundary running from around Vienna, IL to Hopkinsville, KY. 

Scattered storms will likely continue to form periodically along this boundary as it sags southward through the afternoon.

On another note...we're officially at 100 degrees at Barkley Regional/NWS Paducah....our 16th 100+ day this summer.

Original Post:

Happy Wednesday!  We're halfway through another work week, and possibly inching closer to some minor changes in the weather scene.

This afternoon features a weak disturbance sliding southeast over Missouri & Arkansas. This will bring increased cloud cover and a chance of sprinkles or spotty showers over sections of SEMO & NW TN...but most areas of west KY & southern IL will stick with mainly sunny skies and highs in the upper 90's to near 100. 

Aside from the continuing heat, the big story I'm focused on right now is an increase in rain chances over the next few days.  The graphic below shows the 500mb charts (mid-level of atmosphere)...and reads from Wed PM on the top left, to Thu AM on the top right, Thu PM on bottom left, and Fri AM on bottom right.

Notice the H over Texas?  That is the core of the ridge responsible for the intense heat....that ridge will be suppressed over the next few days, allowing for more of a "zonal" (west to east) flow aloft.  You may also notice some blobs of green and yellow over our region on the bottom two images....that represents pieces of mid-level energy (called vorticity) which enhance uplift and typically create more unsettled weather.  This means better chances of rain ahead.  Here's what some of today's forecast model charts are showing:

GFS at 12Z Friday (7AM CDT):

Euro 18Z Friday (1PM CDT):

Euro 18Z Saturday (1PM CDT):

Euro 18Z Sunday (1PM CDT):

I still think it's probably a good idea to take a bit of a "wait and see" approach with this setup....wouldn't be the first time this summer that a good looking rain chance a few days out got drier and drier as the event got closer.  Drought typically leads to more drought.  However, like I said yesterday, the Euro model has performed well this year, and that makes me a little more optimistic that we'll see some rain.  Like usual, I think it will be mainly PM scattered showers and storms....doubt we'll have any one particular day that is a washout.  As for totals, I would expect a pretty wide range, probably 0.25"-1.25", with localized lesser and greater amounts.  Here's the latest 5-day rainfall from the HPC:

Something else noteworthy in the models today...the GFS model is showing signs that we may cool off a little next week!  Here's a peak at next Friday's 850mb temps (about 1,500 ft high....a good first-glance at temperature trends):

Those shades of yellow an orange would likely correspond with highs in the 80's!  We'll need to take this with a big grain of salt though, because models like this want to trend toward our climatological averages (upper 80's) as you get farther into the future.  Still...this is the first time in a while we've seen a signal for a possible cool down.

Finally, a couple of days ago I shared that business was picking up a little in the Atlantic.  That same disturbance is still churning along, and the latest from the National Hurricane Center is that it has a 60% chance of becoming T.D. Five within 48 hours:

 This tropical wave is still about 1,000 miles east of the Lesser Antilles...and while it is becoming more organized, most forecast models currently do not show this system becoming a hurricane.  Because it is at a low latitude (closer to the equator), it will have a hard time generating spin.  That is one thing working against this storm.  The second thing working against it is that it will be moving into a relatively stable atmosphere as it approaches the Caribbean.  Still, things can change, and will be worth watching over the next several days at it moves off to the west/northwest.  Here's the latest model data on the future track of this wave:

That's it for today!  Have a good afternoon, and I'll leave you with your latest 7-Day Planning Forecast...notice we may have a little bit of a cool down to look forward to next week: