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Dangerous heat stress will persist into mid-week.

Increasing rain chances will begin to limit heat stress potential later in the week, especially across North Mississippi and Arkansas.

Discussion

Through tonight: Heat and humidity will remain the main concern in the near term. Early morning satellite imagery/RAP analysis showed the circulation around a large 597dam high centered over the central Plains. Our forecast area will remain on the eastern periphery of this large high through the forecast period. Satellite imagery also showed a disturbance dropping around the eastern side of the high over the Tennessee valley. This has resulted in convection nearing northeast Mississippi already. The bulk of this activity should track just east of our forecast area but due to an outflow boundary, some of the convection may spread into the eastern portions of our forecast area today. Early morning surface analysis had high centered over the northern Gulf. This surface high will remain in place through the forecast period. Together high pressure surface and aloft will contribute to temperatures topping out in the mid 90s to near 100F in spots.

A "Heat Advisory" remains in effect across the forecast area this afternoon as indices range between 106F-110F. The exception to this is currently across Bolivar, Sunflower, & Leflore counties where afternoon heat index values will climb above 110F. Here, an "Extreme Heat Warning" is in effect today. /22/

A "Heat Advisory" remains in effect across the forecast area this afternoon and Monday as indices range between 106F-110F. The exception to this is currently across Bolivar, Sunflower, & Leflore counties where afternoon heat index values will climb above 110F. Here, an "Extreme Heat Warning" is in effect Monday. In addition, on the latest package, confidence in indices climbing above 110F has increased across a larger portion of the forecast area for tomorrow. Therefore, we've expanded the "Extreme Heat Warning" over some central and western portions of the area tomorrow, with a "Heat Advisory" in effect elsewhere.

The aforementioned high aloft will weaken its presence across region as it retreats westward. This will allow troughing along the east coast to deepen across the Southeastern United States. As this happens, another surface boundary will attempt to sink south into the forecast area. This will increase rain chances across the area, potentially bringing at least some temporary relief to the heat. One thing of note during this time, while chances for isolated to scattered convection will increase, the increased northwest flow aloft across the region could yield an MCS or two affecting the forecast area. This is still many days out and will continue to be monitored in future model data, as we draw near to the weekend.