633 FXUS64 KMEG 192334 AFDMEG Area Forecast Discussion National Weather Service Memphis TN 634 PM CDT Thu Jun 19 2025 ...New AVIATION... .KEY MESSAGES... Updated at 557 PM CDT Thu Jun 19 2025 - Hot and humid conditions will start tomorrow and continue well into next week, with heat indices above 105 degrees over much of the Mid-South by Saturday. - Isolated afternoon showers and thunderstorms will be limited to mainly north Mississippi through the weekend and then expand across the Mid-South next week. && .DISCUSSION... (This evening through next Wednesday) Issued at 317 PM CDT Thu Jun 19 2025 Currently...The upper trough that helped to trigger the storms that pushed through the area earlier today has pushed off to the east. The storms themselves have sunk south out of the Mid-South toward central MS. A weak, dissipating, cold front is situated roughly along I-40. A couple of weak showers have developed along this feature. As the airmass recovers across the Mid-South some isolated redevelopment could occur this afternoon and evening south of I-40 but confidence is low. Tonight should be mostly quiet after anything that develops over the next few hours dissipates. A few of the hi-res models show isolated development overnight along the leftover boundary from east-central AR into parts of the Delta of NW MS. Patchy fog is expected to develop thanks to all the recent rains. Upper level high pressure will build over the area over the next few days and then drift east and park over the SE US through next week. As a result the first heat wave of the season is on tap as temps climb into the lower to mid 90s by the weekend. That combined with dewpoints in the mid to upper 70s will result in heat index values at or above 105 degrees. Recent rains and associated evapotranspiration will bolster dewpoints over the next few days. A few counties will reach criteria tomorrow so a Heat Advisory has been issued for parts of east AR and NW MS. That Heat Advisory will likely need to be expanded this weekend to cover most if not all of the area. The heat and humidity will continue through most of next week. Expect isolated afternoon/evening thunderstorms across NE MS through the weekend. This area should expand to cover most of the Mid-South by later in the week as heights fall a bit and southerly flow picks up on the backside of the upper high. && .AVIATION... (00Z TAFS) Issued at 557 PM CDT Thu Jun 19 2025 VFR. Winds south to southwest, less than 5kts. Patchy fog is possible near TUP and MKL. && .FIRE WEATHER... Issued at 306 PM CDT Thu Jun 19 2025 High pressure will prevail through the middle of next week. There will be 20-30% chance of isolated summertime convection each day starting Saturday. Very hot and humid conditions will start tomorrow with temperatures in the mid 90s each afternoon. Fire concerns continue to be low with high afternoon relative humidities and moist fuels. && .MEG WATCHES/WARNINGS/ADVISORIES... AR...Heat Advisory from 11 AM to 8 PM CDT Friday for ARZ035-048-049- 058. MO...None. MS...Heat Advisory from 11 AM to 8 PM CDT Friday for MSZ007-010-011- 020. TN...None. && $$ PUBLIC FORECAST...SJM AVIATION...CJC