Back to summer to start the week, then thunder arrives by mid-week

Although we enjoyed below average dewpoints to end last week, humidity levels are back near normal for summer with another hot day on tap tomorrow as highs reach the upper 90s. However, the oppressive heat will improve a bit as we head into Wednesday, with high pressure deteriorating and rain chances increasing. A pattern that favors chances for thunderstorms will persist through at least Friday before leading to a mainly dry and fairly comfortable weekend. Lets get into the details of the forecast below.

GFS modeled 500 mb (18,000') height anomalies, valid late Wednesday night. Lower than normal pressure (indicated by light blue) over the Mid-South indicates a low pressure disturbance over the area, which brings our t'storm chances.

As high pressure retreats on Wednesday, a mid-level shortwave (or area of lower pressure in the middle portions of the troposphere) and weak cold front will be the primary cause of rain chances for the latter portion of the work week. The mid-level feature in the atmosphere allows thunderstorms to more easily form during the heat of the day beginning Wednesday as it draws closer to the region. The strength of this shortwave will also lead to chances of thunderstorms at night (particularly on Wednesday night) providing enough lift to fuel some scattered storms even without the mid-day sun. The best chance of thunderstorms this week could be Wednesday night. Though severe weather is not expected to be widespread, a few strong storms are possible as the potent shortwave moves through.

A Marginal Risk (category 1/5) severe weather risk exists Wednesday into Wednesday night for the metro. Widespread severe weather is NOT anticipated at this time.

By Thursday, the disturbance will be exiting the region, but with the weak cold front near the area, scattered showers and thunderstorms will be possible Thursday and Friday before high pressure re-builds into the area heading into the weekend. The result will be slightly lower temperatures for the region from Thursday through Saturday. If you happen to get a thunderstorm during the daytime hours, you'll enjoy some relief from the heat, but also increased humidity.  Most of Saturday and Sunday look dry and fairly comfortable for early August, though temps start climbing again as we head into early next week.

You can check out the full MWN Forecast here or within the MWN mobile app which you can find links to below.

William Churchill
MWN Social Media Intern

Erik Proseus
MWN Meteorologist

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