099 FXUS64 KJAN 111724 AAB AFDJAN Area Forecast Discussion...UPDATED National Weather Service Jackson MS 1224 PM CDT Sat Sep 11 2021 .UPDATE... Updated for 18Z aviation discussion && .AVIATION... 18Z TAF discussion: VFR conditions will prevail through the period. A layer of smoke aloft may reduce slant-wise visibilities this afternoon at GLH, GWO, HKS and JAN./GG/ && .DISCUSSION... The forecast is still on track to be another warm, dry day. Satellite imagery not showing any cloud cover, but an expansive layer of smoke was increasing from the northwest./GG/ Prior discussion below: Today and tonight: Pleasant and dry weather conditions will stick around as a broad surface high extending along much of the Atlantic coast shifts eastward today. As mid level ridging builds in more and with full sunshine abounding, temps will be a bit warmer during the daytime though still seasonable. It will be cool again tonight, though not quite as cool as the past couple of nights as surface vectors veer gradually back to include a more southerly component. With a slight uptick in surface moisture, patchy fog can't be ruled out for early Sunday morning. /DL/ Sunday through Friday: Flat upper ridging will be in place at the beginning of the forecast period with the region on the western side of surface high pressure centered across the Carolina coast. Plentiful moisture will exist in the Gulf of Mexico in association with an area of disturbed weather/low pressure system near Mexico. As this feature moves north, moisture will also advect north into our region. By Monday, thanks to good moisture transport, PW values will be around 2.3 inches in the southern half of the forecast area, eventually reaching at least 2 inches across the whole area by mid-week. Those nice 50s and 60s dewpoints will be a memory for us this coming week as the lower 70s dewpoints will return. All of this will mean increased rain chances through much of the week for the region. While most of this will come in a diurnal pattern, there is a better than usual chance of showers lingering overnight in our tropical airmass. Guidance indicates, at least initially, little in the way of instability so current thinking is that much of this will be in the form of showers with isolated thunderstorms possible. With deep tropical moisture in place, there will be concern for efficient heavy rainfall and localized flash flooding. Will hold off adding anything to the HWO/graphics for now, but may need to be added in future forecast packages. With cloud cover and rain potential, temperatures will be kept in check. Highs through much of the week will be in the 80s, with lower 80s possible in the southern part of the forecast area. Overnight lows will be muggy with mostly readings in the 70s but some upper 60s will be possible. /28/ && .PRELIMINARY POINT TEMPS/POPS... Jackson 88 64 91 70 / 0 0 13 6 Meridian 87 63 89 68 / 0 0 12 4 Vicksburg 89 64 92 72 / 0 0 10 7 Hattiesburg 88 65 89 70 / 0 2 34 9 Natchez 87 64 89 70 / 0 0 23 12 Greenville 90 63 92 69 / 0 0 3 3 Greenwood 89 64 92 69 / 0 0 3 3 && .JAN WATCHES/WARNINGS/ADVISORIES... MS...None. LA...None. AR...None. && $$