Rain Chances, Cool Temps, and a Peek at the BBQ Fest Forecast

We've gotten a taste of early summer this past weekend with increased humidity, daytime temps in the 80s, and warm overnight lows. That all changes though as a cold front moves towards the region.

A look at surface temperatures this morning shows a clear boundary through the central US separating the warm and muggy conditions we have been experiencing here and the much cooler and drier conditions across parts of the Plains. This temperature gradient is associated with a potent cold front for this time of year. As a result we can expect a good amount of rain as it approaches as well as near record low temperatures for this time of year (into the 40's in many areas!). We'll also take an early look at the BBQ Fest weekend forecast. Lets get into some specifics as to what you can expect in the Mid-South this week.

Surface temps at 11am CDT showing a cold airmass across the Plains and west and a very warm one in the east.

Above you can see the potency of the aforementioned cold front. There is a very sharp gradient of surface temperatures where it quickly goes from 70 degrees to the mid 40's over a short distance. This front will not be quite as strong by the time it arrives here on Wednesday but it will still be rather significant for a mid-May storm system. Another factor worth mentioning is that once the front nears the area, it will have some trouble trying to continue moving through as the upper level wind parallels the front and low pressure forms on it just to our east. As a result, rainfall associated with the front could train over our area, which could lead to higher rain totals.

GFS Total Precipitation through Thursday at 1 AM

Precipitation totals from one particular model (not a forecast) show rain totals right around 1 inch in the Memphis metro. There's a sharp gradient between values closer to 2 inches northwest of our area. We will have to keep an eye on where the heaviest precipitation sets up, as this area will feature the highest potential for flash flooding. Locations west of the MS River (including Crittenden Co in the metro) are already under a Flash Flood Watch due to this potential. Right now it looks like this area will stay to our west but we will be sure to let you know if that changes.

Storm Prediction Center 3-day Outlook shows the slight risk of severe weather off to our east

Another factor that is surely on the minds of our readers is the threat of severe weather. Thankfully chances for severe weather look quite low due to the system weakening as it approaches the area. In fact, chances for scattered non-severe thunderstorms appear highest late tonight and tomorrow. By Wednesday, chances for rainfall will be the highest, but overall expect this activity to be weaker in nature due to less available heat for the storms to use as energy and low pressure that will stay east of the metro, putting us in the "cool sector" of the system. As you can see from the day 3 severe weather outlook above, the higher chances for severe weather are to our east where more energy from daytime heating on Wednesday should be present, as well as it's position in the warm sector of the developing low. Activity should wrap up Wednesday night, ushering in cooler temperatures for the end of the work week.

GFS model Minimum Surface Temperatures Thursday morning

Thursday morning looks to be the coolest of the week with temperatures in the upper 40's (over 10 degrees below normal and nearing the record low for the date!). High temperatures will also likely remain in the 60's on Wednesday and Thursday due to the much cooler air mass and rain on Wednesday. By Friday we should see highs return to the 70's.

A brief note on BBQ Fest this weekend: Temperatures look great with highs in the 70's and lows in the 50's. However, an upper-level disturbance looks to come through the area this weekend which could bring small rain chances starting Friday afternoon. Any activity appears to be scattered and light at this time. Stay tuned to us for updates and check our forecast daily on the web or via our apps!

William Churchill
MWN Social Media Intern

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