Area Forecast Discussion
Issued by NWS Jackson, MS
Issued by NWS Jackson, MS
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084 FXUS64 KJAN 141725 AAC AFDJAN Area Forecast Discussion...UPDATED National Weather Service Jackson MS 1225 PM CDT Tue May 14 2024 ...New AVIATION... .MESOSCALE UPDATE... Issued at 1021 AM CDT Tue May 14 2024 Rest of Today...Troughing associated with a closed low centered over East Central Missouri will continue to push east through the region today. Associated with this low, is a weak cold front that`ll likewise shift east through the forecast area during the course of the day. This front, in conjunction with available instability from daytime heating, will yield some scattered showers and possibly an isolated thunderstorm or two this afternoon into early this evening, especially across East and Southeast Mississippi. As the front moves though, rain chances come to an end, and skies will slowly clear from west to east through the late afternoon and evening hours. The ongoing forecast is in good shape. Other than some minor adjustments to hourly elements of the forecast, no major changes will be made on this morning`s update. /19/ && .DISCUSSION... Issued at 415 AM CDT Tue May 14 2024 Today and Tonight: The bulk of the precipitation has move north and east of the area this morning, but a few isolated showers will continue to be possible through the morning. The main upper trough axis will move across the area today and this may kick of isolated to scattered showers/storms mainly for the northern and eastern portions of the area. WIth limited moisture/instability expect any storms that do develop this morning into the afternoon hours to remain below strong/severe limits. Drier air will build in this afternoon and expect the activity to move east of the area later this afternoon and evening along with clearing skies. Skies will be mostly clear overnight, with lows in the low 60s. /15/ Wednesday through Monday: A split flow pattern will continue across the CONUS through next weekend. Shortwave ridging over the Gulf Coast will prevail through the day Wednesday and into Wednesday night, allowing for temps to rebound into the mid and upper 80s Wednesday afternoon. Then Thursday into Friday, model guidance indicate that a strengthening southern stream jet and positively-tilted shortwave trough shift eastward across the Southern CONUS. Increasing lift and instability in advance of this system will increase the possibility for organized severe thunderstorms in the Thursday-Friday window. ECMWF/CMC solutions generate convection over East Texas Thursday and steers a likely MCS toward central LA/MS Thursday night as well as re-development closer to the central Gulf Coast Friday evening overnight. Meanwhile the GFS/NAM solutions are less robust with Thursday`s East Texas convection escaping the Plains and hold off until Friday before brining more intense convection into our forecast area. If the storms hold off in our area until Friday, instability will have a greater chance to build northward in advance of the system. GFS paints 1500-2000 J/kg of MLCAPE across the southern tier of our forecast area by Noon on Friday with 50-60 kts of westerly deep-layer shear across the area. These conditions would certainly support organized severe thunderstorms across portions of our forecast area. The big *BUT* that must be emphasized is that with these southern stream waves exciting storms upstream over the Southern Plains, it has occurred several times recently that sheared storms to our west have the chance to spread farther east and faster if an organized MCS can develop. Therefore will highlight the Thursday evening into Friday period as our next chance for severe storms. SPC has introduced a Marginal Risk for severe storm to our southwest before 12Z Friday and Slight Risk (15% area) for central/northeast LA and central/southern MS after 12Z Friday. To not get overly specific with timing yet, will combine this threat into one graphic for the previously-mentioned time range and leave further refinement to the next few updates as the details of the wave come into better focus. In addition to the threat of severe thunderstorms, the strong shear and instability will be paired with increasing humidity in the region. Latest guidance pushes PWAT values into the 1.7-2.0 inches range by Friday, leading to a threat for heavy rain with storms. Localized flash flooding could be a concern, especially for parts of our area that have seen the most rain in the last week or two. Current FLASH soil moisture values are most saturated from around Richland and Madison parishes southeast to Clarke and Wayne counties. A quick 2-3 inches of rain over any of those areas could easily lead to ponding water or flash flooding. A Limited threat area for Flash Flooding has therefore been introduced for Thursday and Friday as well. The upper-level trough axis should be clearing east of our forecast area by Saturday night, so trended POPs lower than guidance Saturday night and Sunday based on latest trends in deterministic guidance. Peaking ahead into next week, the flow looks to become better phased across the CONUS as a trough deepens over the western CONUS and a ridge amplifies over Mexico and the western Gulf Coast region. The likelihood of high temps reaching the lower 90s increases to start the new work week, with average temps expected to be 5-10 degrees above normal for much of the area. /NF/ && .AVIATION... (18Z TAFS) Issued at 1224 PM CDT Tue May 14 2024 MVFR flight categories will gradually give way to VFR flight categories this evening, as both clouds and convection clear the area in the wake of a cold front that`ll push east through the region. Some patchy fog will be possible across mainly Southeast Mississippi early Wednesday morning. This could result in a brief bout of MVFR/IFR flight categories at KPIB & KHBG. Fog will erode quickly afternoon sunrise, with VFR flight categories prevailing areawide. Winds today will be from the southwest around 10 knots, with some isolated gusts between 15-20 knots possible at times. Tonight, winds will be more westerly and subside to 3-5 knots. /19/ && .PRELIMINARY POINT TEMPS/POPS... Jackson 61 85 63 85 / 0 0 0 10 Meridian 61 86 61 88 / 10 0 0 10 Vicksburg 60 86 64 85 / 0 0 0 20 Hattiesburg 63 88 64 88 / 10 0 0 10 Natchez 60 86 64 84 / 0 0 0 20 Greenville 63 85 65 87 / 0 0 0 10 Greenwood 62 84 64 87 / 10 0 0 10 && .JAN WATCHES/WARNINGS/ADVISORIES... MS...None. LA...None. AR...None. && $$ /19