FXUS64 KJAN 190558 AAC AFDJAN Area Forecast Discussion...UPDATED National Weather Service Jackson MS 1258 AM CDT Tue Aug 19 2025 ...New AVIATION... .MESOSCALE UPDATE... Issued at 819 PM CDT Mon Aug 18 2025 Rest of Tonight...Convection continues to wind down across the forecast area this evening. While the majority of the CWA will remain quiet through the overnight hours, a stray short-lived shower can't be ruled out during the overnight hours as a result of the deeply moist airmass in place across the region and lingering outflow boundaries meandering about the area. Some residual high clouds will remain over the area overnight, as lows fall into the middle 70s. The ongoing forecast is in good shape. Both the "Heat Advisory" and "Extreme Heat Warning" from earlier today were allowed to expire at 8 PM. Unfortunately, another will take its place at 10 AM Tuesday, as high levels of heat & humidity continue to grip the region. Until then, I'll make some adjustments to hourly elements of the forecast to better fit current trends. Otherwise, no major changes will be made on this evening's update. /19/ && .DISCUSSION... Issued at 140 PM CDT Mon Aug 18 2025 Tonight and Tuesday: Similar to Sunday afternoon, local radars were showing isolated showers and thunderstorms developing across the whole CWA. The movement of the convection was to the southwest and scattered storms will be possible across our central and southern zones into early evening before the convection will dissipate. The microburst composite parameter has increased over the last several hours and shows potential so a few strong wind gusts can be expected. Otherwise, high pressure surface and aloft centered just to our west will continue through Tuesday and actually peak Tuesday before starting to break down. Tuesday will be another day of near record temperatures across our delta region. The hot temperatures will combine with high humidity to result in heat index values above 105F this afternoon and again Tuesday afternoon. At locations along the Mississippi river heat index values are expected to exceed 110F this afternoon and again Tuesday. An Extreme Heat Warning has been issued for this area today and Tuesday. Elsewhere, a Heat Advisory remains in effect until 8PM this evening and a Heat Advisory has been issued for Tuesday as well. Lower rain chances are expected Tuesday and any thunderstorms that develop will do so mainly during the afternoon and across our southern zones. A few storms may produce strong gusty winds again. /22/ Wednesday Onwards: Little will change over the next week, as high pressure remains anchored over the region. Isolated afternoon and early evening showers/thunderstorms are expected every day. All indications at this time point to non-severe characteristics for this convection but there is still a chance for damaging winds should a cell or two overachieve. A weak trough will rotate around the upper level ridge Thursday which will help moderate our temperatures back down into the 90s, allowing for a relief from our 105+ heat indices across the area. Upper level troughing will continue over the area into the weekend, bringing cooler temperatures and a slight increase in afternoon storm coverage; with the greatest coverage along and south of I-20. /OAJ/ && .AVIATION... (06Z TAFS) Issued at 1258 AM CDT Tue Aug 19 2025 Patchy fog cannot be ruled out around daybreak this morning. Isolated to scattered convection may result in brief categorical reductions mainly this afternoon through early this evening. Otherwise, VFR conditions are anticipated through the TAF period. /DL/ && .PRELIMINARY POINT TEMPS/POPS... Jackson 75 98 73 93 / 10 50 30 50 Meridian 74 97 72 92 / 10 30 20 50 Vicksburg 75 9873 92 / 10 50 40 50 Hattiesburg 74 98 74 94 / 10 30 20 60 Natchez 74 96 72 91 / 10 40 30 50 Greenville 75 98 73 94 / 20 50 30 20 Greenwood 75 98 72 94 / 10 50 30 30 && .JAN WATCHES/WARNINGS/ADVISORIES... MS...Heat Advisory from 10 AM this morning to 8 PM CDT this evening for MSZ026>033-036>039-043>046-049>052-055>058-062>066- 072>074. LA...None. AR...None. && $$ 19/22/OAJ/DL