Area Forecast Discussion
Issued by NWS Jackson, MS
Issued by NWS Jackson, MS
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170 FXUS64 KJAN 060559 AFDJAN Area Forecast Discussion National Weather Service Jackson MS 1259 AM CDT Sat Jul 6 2024 ...New AVIATION... .MESOSCALE UPDATE... Issued at 956 PM CDT Fri Jul 5 2024 At mid evening local radars showed scattered thunderstorms gradually weakening over the southwest portions of our CWA. With the loss of daytime heating much of the convective potential will end but with the weak frontal boundary dropping through the CWA, there will be a low chance of redevelopment through the remainder of the night generally south of Highway 82. Patchy early morning fog will be possible in the areas that received significant rainfall but dense fog is not anticipated. /22/ && .DISCUSSION... Issued at 259 PM CDT Fri Jul 5 2024 Rest of this evening through Saturday... Afternoon analysis indicates frontal zone sinking southward across the region, leading to widespread showers & storm development across the Natchez Trace corridor & southward. This is in response to a highly destabilized & moist tropical environment, favoring tropical- like downpours & QPF maxima of >3-4" common, with locally higher amounts possible. The ongoing "Limited" for flash flooding remains valid into this evening around 10PM or so. There have been a few cores that have sparked up there or oriented orthogonal to light west-northwest low-level shear, so some strong-isolated severe storms remain possible through the evening. Expect convection to wind down slowly overnight, with a majority of thunder potential gone around 9-10PM & some showers persisting through around midnight. HRRR indicates some redevelopment in the wake of this ongoing line, but current radar trends seem to be focused further northwest. There could still be some isolated potential in the wake, but likely not as vigorous, unless moving through untapped thermodynamic profiles. With clouds & deep moisture, near to seasonably warm lows in the low-mid 70s are expected. As the shortwave trough swings across the northeast & another into the northern Plains, the mid-level ridge will flatten & build more into the northeast Gulf. This will also be moderated by Tropical Storm Beryl, which should gradually become more organized into the weekend across the Bay of Campeche into the southwestern Gulf of Mexico on the trek near International Border & south Texas coast. This should keep a deep, anomalous & near climatological maximum moisture profiles of PWs of 2.25-2.5 inches. Expect rain chances to slowly begin to creep up before midday, becoming more scattered near midday & widespread south of I-20 into Saturday aftn. Can`t rule out some stronger storms again into the aftn-evening hours. HREF prob match mean of >3" are lower than today but remain possible in the Hwy 84 to I-59 corridors. Holding off any introduction for flash flooding in the HWO graphics at this point. Even with more seasonable highs in the upper 80s to low 90s, sfc dewpoints pooling in the 77-80 degree range will again favor some potential increased heat stress for areas along & south of I-20 & east of the MS River. Added a "Limited" heat in the HWO graphics, with heat indices peaking near or in excess of 105F briefly. Held off on a heat advisory for now as convection will modulate the potential, but will need to be reevaluated. /DC/ Saturday night and Sunday: Though a surface front will sag briefly into the northern portion of the area this weekend, it appears any relief in the form of lower dewpoints will mainly be confined to the Hwy 82 corridor and northward. A moist airmass with dewpoints in the mid to upper 70s and PW of 2-2.5 inches will remain entrenched across the remainder of the area. Showers and thunderstorms ongoing from the daytime Saturday will linger into the early evening across mainly south MS and central LA before diminishing overnight. Then another round of showers and storms is likely with daytime heating on Sunday. Ultimately, the front will begin to retreat northward by the daytime Sunday. Though daytime temps Sunday may be limited by increasing coverage of clouds and convection, there may still be enough opportunity across southern portions of the area for early heating to result in heat indices rising to near critical thresholds. For this reason, we will maintain the limited heat stress hazard graphic into Sunday. Monday through next Friday: As an upper level trough persists over the central part of the country and a more subtle ridge axis extends from the northern Gulf to along the East Coast, southwesterly to westerly upper flow will continue over our area for much of next week. This pattern will help to maintain a steady feed of deep layer moisture across our area, which will keep at least scattered diurnal convection around each day. We continue to monitor what will happen with the remnants of Beryl, as this may help to enhance rain chances particularly Tuesday and Wednesday. Toward the end of the week, the eastern ridge may begin to wield greater influence, which could bring warmer and drier conditions. Of course, we must talk about those pesky heat indices. With higher rain chances especially earlier in the week, uncertainty is high with respect to peak temps and heat indices each day. However, at least limited heat stress issues may persist especially over the southern half of the area next week. /DL/ && .AVIATION... (06Z TAFS) Issued at 1255 AM CDT Sat Jul 6 2024 A considerable amount of IFR/LIFR category stratus is expected for mainly southeast portions of the forecast area through early to mid morning, then expect quickly improving conditions during the late morning. Scattered SHRA/TS will be most prominent during the afternoon to early evening for the southern half of the area. Otherwise, VFR conditions and light surface wind will prevail. /EC/ && .PRELIMINARY POINT TEMPS/POPS... Jackson 74 90 74 92 / 10 50 20 50 Meridian 73 92 73 94 / 20 60 30 60 Vicksburg 74 89 75 91 / 10 40 20 40 Hattiesburg 76 94 76 94 / 30 70 20 60 Natchez 74 90 75 91 / 20 50 20 50 Greenville 73 90 75 91 / 0 30 20 50 Greenwood 74 91 75 93 / 0 30 10 50 && .JAN WATCHES/WARNINGS/ADVISORIES... MS...None. LA...None. AR...None. && $$ 22/DC/DL/EC