Area Forecast Discussion
Issued by NWS Jackson, MS
Issued by NWS Jackson, MS
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582 FXUS64 KJAN 180618 AAB AFDJAN Area Forecast Discussion...UPDATED National Weather Service Jackson MS 118 AM CDT Sat May 18 2024 ...New AVIATION... .MESOSCALE UPDATE... Issued at 938 PM CDT Fri May 17 2024 Mid evening surface analysis had a stalled frontal boundary just south of our southeast most zones. Regional radars only had a few light returns across our southern zones. This convection was occuring downstream of an approaching shortwave trough as seen on mid evening satellite imagery. Regional radars showed some more vigorous convection along the stalled boundary and just off the Texas and southwest Louisiana coasts. As the shortwave continues to approach our western zones by morning, additional convection is expected to develop and move along the boundary. Some models move the boundary to the north by morning allowing some of the convection to track across our southeast. Isolated severe storms capable of damaging wind gusts and hail to quarter size will be possible. If the storms due in fact track across our southeast, they will also produce locally heavy rainfall over already saturated soils leading to excessive runoff. Thus, the Flash Flood Watch will remain in effect for our southeast. /22/ && .DISCUSSION... Issued at 244 PM CDT Fri May 17 2024 Through Saturday: Overall fcst is running generally on track. Water vapor/RAP analysis this aftn indicated stalled upper low parked over the central Plains, with widespread moist ascent over the warm frontal boundary along the Gulf Coast. Earlier heavy rain has let up, with continued potential for some late aftn redevelopment in the Pine Belt. With trends shifting southward in convective allowing models, the flooding threat/Flood Watch were adjusted southeastward through the evening hours & trimmed back through Saturday morning. Nearly 99th percentile PWs & 925-850mb 340-350K Theta E will persist across southeastern portions of the area. Increased destabilization is ongoing as anticipated in a tight gradient in the Pine Belt, with best potential for any aftn redevelopment in the Hwy 98 corridor & to I-59 corridors. The ongoing severe potential could be at earliest in the next few hours but most likely into late evening to overnight in the Hwy 98 to I-59 corridors in the Pine Belt in southeast MS. Adjustments have been made to Severe threat in HWO graphics, with main focus being for damaging wind, hail quarter to golf ball size & tornadoes possible, especially in the Hwy 98 to I-59 corridors. Some low tornado threat in sfc mesoanalysis exists if any aftn redevelopment occurs, with large hail up to golf ball size most likely in the moderately unstable air & 50-60kts mean bulk shear. Damaging winds & some hail threat will persist into the overnight hours. Flash flooding threat will likely peaking back up in the Pine Belt late tonight but made adjustment to current Flood Watch to account for a smaller areal configuration & trimmed it down in time. HWO graphics were adjusted accordingly. As the upper low swings into the area on Saturday, some persistent westerly bulk shear around 30-35kts & mid-level lapse rates around 6-6.5 deg. C/mid 20s vertical totals & freezing levels around 12.5-13kft that could support some isolated severe threat with damaging winds & quarter size hail. Timing looks to be the mid- morning through early evening hours. After the rain & storms move into the Pine Belt in the morning, there could be the a brief lull in the Natchez Trace corridor before more scattered to numerous showers & storms move across the eastern-central portions of MS. In terms of sensible weather, expect gradual moderation into the low-mid 80s & some increase in heat/humidity. Late weekend through early next week (Sunday-next Thursday)... Late weekend (Sunday): Upper low will swing into the Appalachians, with ridging at the sfc & aloft building in from west-east. This will drive in drier air into Sunday. Expect moderation of highs in the mid- upper 80s Sunday, with increasing potential heat & humidity. Next week (Monday-Wednesday): As the mid-level & sfc ridge builds in, increased warm advection will bring up low-level temps into the upper teens to low 20s degree C at 850-925mb layers. Expect highs to moderate to seasonably warm into the low 90s & lows in the mid-upper 60s while to low-mid 70s northwest of the Natchez Trace. Heat & humidity will be on the rise around midweek with heat indices climbing into mid-upper 90s. Low-level return flow won`t pick back up until by late Monday evening through midweek, with rain & storm chances picking back up around mid-late week, northwest of the Natchez Trace on Wednesday & north of I-20 on Thursday. There could be some organization to the next trough/frontal system for some organized convection late week, but there is plenty of time to iron out as we get closer. /DC/ && .AVIATION... (06Z TAFS) Issued at 118 AM CDT Sat May 18 2024 VFR/IFR flight conditions for majority of TAF sites with the exception of VFR flight conditions at GLH to begin the TAF period. VCSH and -RA will be possible tonight and Saturday as a frontal boundary moves across the area. Near 17-18Z Saturday, flight conditions are expected to improve to VFR across all TAF sites. /SW/ && .PRELIMINARY POINT TEMPS/POPS... Jackson 84 65 87 67 / 30 10 10 0 Meridian 85 64 88 64 / 50 20 10 0 Vicksburg 86 67 88 68 / 20 10 0 0 Hattiesburg 86 66 89 66 / 40 10 10 0 Natchez 85 66 88 67 / 20 10 0 0 Greenville 85 67 88 69 / 40 0 0 0 Greenwood 84 65 88 68 / 60 10 0 0 && .JAN WATCHES/WARNINGS/ADVISORIES... MS...Flood Watch until 7 AM CDT this morning for MSZ057-058-064>066- 072>074. LA...None. AR...None. && $$ DC/DC/SW