521 FXUS64 KJAN 050237 AAA AFDJAN Area Forecast Discussion...UPDATED National Weather Service Jackson MS 937 PM CDT Wed Jun 4 2025 ...New MESOSCALE UPDATE... .MESOSCALE UPDATE... Issued at 937 PM CDT Wed Jun 4 2025 Rest of tonight... A quiet evening is on tap across the Gulf Coast region. Water vapor imagery & RAP/upper air analysis this evening indicate upper low over the northeastern Gulf, with light southerly to variable low-level winds. This has kept some dry air around, but moisture impinging from the east, where some showers have lingering near the Pine Belt to MS/AL state line to Golden Triangle region. Sfc front is stalled in the ArkLaTex, with sfc ridging in the between. Evening upper air data indicates near normal atmospheric humidity across the I-55 corridor while surrounding areas are closing in with seasonably high precipitable water (PWs) values around 1.6 to 1.9 inches. For tonight, lows will be seasonably warm, some 5-8F above (68-74F). Crossover temperatures don`t look to be able to be achieve due to mixing of aftn dewpoints into the mid 60s along & southeast of the Natchez Trace corridor to low 70s northwest of the Natchez Trace. Limited southerly return flow lowers confidence of advection fog overnight. If any occurs, it will likely be in sheltered areas & low-lying river valleys & any areas that radiate more efficiently. HREF dense fog probabilities indicate a low chance (20-35%), but confidence is too low to introduce any HWO graphic. Updates are out. /DC/ && .DISCUSSION... Issued at 310 PM CDT Wed Jun 4 2025 Tonight: Persistent light southerlies have resulted in increasing humidity and with it increasing temperatures. This pattern brings an end to the somewhat cooler and noticeably drier pattern of the last several days as rain chances, particularly during peak heating, return. Initial showers and an isolated rumble of thunder or two across southern portions of the area from this afternoon will be lingering and then dissipating overnight. Lows tonight fall generally to around 70 F with temperatures a bit higher, 72-74, in the Mississippi Delta. /86/ Thursday through Tuesday: A significant change to the upper level pattern will eventually result in stormier conditions for the entire forecast area as we go through the weekend into early next week. Until then, upper level ridging over the southeast CONUS will deflect the westerlies to our west and north, and this will result in mostly dry weather for Thu through Friday with increasingly hot daytime conditions. Spotty convective rainfall could occur in the hot conditions over eastern portions of the forecast area, but would not depend on this to provide much relief from the heat. By this weekend, the upper level ridge will shift to the western CONUS while a large longwave trough sets up over the east. The resulting cyclonic northwesterly flow over the MS Valley region will encourage a cold front to move southward and approach northern portions of our area, where it will stall and provide a focus increased thunderstorm chances. Increased mid/upper level flow could bring an organized convective system into our area as early as Friday night, but it is more likely that we`ll see the increase in MCS activity later Saturday into Sunday, especially for locations along/south of I-20. Given the hot and unstable air south of the front, there will be plenty of fuel for intense storms, and we continue to indicate the severe weather potential in our graphics. As we get closer in time and model solutions move more into the CAM time windows, mesoscale influences will hopefully become more apparent, and this will allow us to provide more timing detail and other specifics on hazard types and overall intensity. We may also see heavy rainfall emerge as a greater impact concern depending on where MCS paths converge the most. Heading into early next week, the active weather pattern will remain generally the same, but should shift south and thereby increase storm/rainfall threats for locations mainly south of the I-20 corridor. Confidence is quite low however at this time range on weather impacts. /EC/ && .AVIATION... (00Z TAFS) Issued at 627 PM CDT Wed Jun 4 2025 Outside of isolated showers & rouge storm in eastern & southern areas before 04/02Z Thursday, VFR conditions prevail through 09/10Z Thursday when ceilings lower to MVFR/IFR, mainly at GTR, MEI, PIB & HBG. Any reductions will improve after 04/14-16Z Thursday as morning mixing increases & ceilings lift. Some isolated showers & storm or two can`t be ruled out Thursday aftn to evening. Generally light southerly winds, less than 10mph sustained/gusts, are expected the next 24 hours. /86/DC/ && .PRELIMINARY POINT TEMPS/POPS... Jackson 71 91 73 92 / 0 20 0 20 Meridian 69 91 71 93 / 10 20 0 30 Vicksburg 73 92 74 93 / 0 20 0 10 Hattiesburg 71 93 74 95 / 10 20 0 30 Natchez 71 90 73 91 / 10 10 0 10 Greenville 74 90 74 91 / 10 30 0 20 Greenwood 71 92 73 92 / 0 30 0 30 && .JAN WATCHES/WARNINGS/ADVISORIES... MS...None. LA...None. AR...None. && $$ DC/EC/DC