textproduct: Jackson

KEY MESSAGES

- Dense fog ongoing across the area this morning

- A storm system with severe thunderstorms and locally heavy rain remains a concern late this evening through Tuesday afternoon - Much cooler and drier air will surge into the area Wednesday and continue the remainder of Thanksgiving Week.

- Heavy rainfall could become a concern by early next week for northwest portions of the area.

DISCUSSION

Issued at 402 AM CST Mon Nov 24 2025

This week into next weekend...

Today: Synoptic analysis and water vapor imagery indicate shortwave ridging building across the region. Drier air persists in the region this morning (PWs around 0.6 inches and dewpoints in the 46F to 50F range). 1024mb sfc high is situated across the OH Valley and expansive southward into the Gulf Coast states. Main concerns first are dense fog this morning. HREF dense fog probs indicate nearly 40 to 60 percent, with dense fog being observed in Pine Belt and expanding northward along the Pearl River Valley. Based on this, added a hazard graphic for dense fog, with Elevated along and south of Interstate 20 and Limited to the north. A Dense Fog Advisory has been issued from Copiah to Clarke, Lincoln to Jones and Marion to Forrest in MS. This should lift around 9AM.

Strong cold core is moving out of Intermountain West in CO into the Central Plains in KS to OK border, with strong vorticity advection swinging southward across the Red River Valley to south- central TX. Increased upper jet will overspread the Plains, Mid MS Valley to OH Valley, with favorable upper jet dynamics. Surface low and frontal system will swing eastward. The strongest forcing will remain well off to the north into the Ozarks to Mid MS to OH Valleys. However, there will be enough forcing from a secondary spoke of energy over central TX, low level jet (35kts to 45kts) and frontal convergence to spark increased rain and storm coverage. The onset of rain will be as early as just after noon in the extreme northwest Delta and storms by mid-afternoon. The severe thunderstorm potential will ramp up after 6PM to 8PM this evening and last through Tuesday morning around 5AM. Convective allowing models (CAMs) are coming in focus, with a forced squall line or QLCS propagating from southwest to northeast across the area. There could also be discrete supercell development potential a touch earlier ahead of the forced squall line, which could have all modes of severe weather possible in these severe storms. The QLCS will be the main focus, with the best severe potential in the northwest Delta, continuing northeast towards the Golden Triangle and Natchez Trace corridor around midnight to 1AM and persisting through around 5AM to the southeast. Strong mean southwesterly shear (40-65kts) will set up but remain mostly line-parallel. Strong moist advection will drive dewpoints back up into the 64-68F degree range along and south of Interstate 20. With strong southwesterly mean bulk shear, lapse rates, favorable thermo (around 6C mid level lapse rates, 25 to 28C vertical totals and 300 J/kg to 700 J/kg MLCAPE), severe threat and advertisement in HWO of Slight/Marginal risk remains warranted. Along the stronger southern spoke of energy, there will be sufficient height falls for more organized convective line in the extreme northwest Delta and northeast bowing segments remain a concern for orthogonal bulk shear orientation and resultant potential for damaging wind gusts of 60mph and tornadoes, with some hail threat at the onset this evening. There will be a brief break in activity, before more veered flow but frontal convergence could get some strong to isolated severe activity going again. Timing of this would be from 9AM to 5PM, but ending as early as 3PM in east MS.

Strong cloud bearing layer flow (45-50kts in the 850-300mb layer), PWs around 1.6 to 1.8 inches and 850mb Theta E around 330K favor quick, locally heavy convective downpours. There is increased confidence of heavy rainfall totals, as CAMs indicate a stripe of training convection somewhere along and north of a line near the Natchez Trace extending up into the Golden Triangle area. Some areas could see a quick 3 to 4 inches, with locally higher amounts, in a short duration. Decided to add a hazard graphic for flash flooding in these areas late tonight through early Tuesday morning. In addition, surface low won't be really deep but there will be some pressure gradient (4mb) for some gusty gradient winds, at most around 25mph gusts or a touch higher at times.

Seasonably warm conditions will be expected both today and Tuesday, highs some 10F to 15F above (72F to 82F), while very seasonable warmth Monday night, some 20F to 24F above (59F to 66F). Some record warm lows are possible for sites along and north of Interstate 20.

This pattern favors rain chances through around daybreak Wednesday before strong frontal passage brings a pattern change. In the wake, mean northerly flow/subsidence, 1028-1032mb surface high and drier thermal profiles (PWs less than half inch) favor dryness and seasonably cooler conditions, 5-8F below, into late this week on Thanksgiving into late week (Thursday into Friday). Low temperatures in the low 30s (possibly below freezing) to upper 30s are possible both Wednesday night through Thursday night, with a light frost/freeze possible Thursday night. A more amplified synoptic and surface reflection will take place into next weekend. Relevant portion of previous long term discussion is below. /DC/

Next weekend: It is definitely worth mentioning the day 7-8 period for this forecast as quite an active weather pattern could develop over much of the central CONUS by that time as a major longwave trough sets up over the Rockies into the Plains while a strong ridge builds up the East Coast, thus placing our area in favorable deep southwest flow aloft for several rounds of showers and storms. As of now, global models are showing increasing potential for heavy rainfall to develop, especially over the ArkLaMiss Delta region where it would be supported by the current La Nina. This is just something to keep an eye on for the next few days. /EC/

AVIATION

(12Z TAFS) Issued at 531 AM CST Mon Nov 24 2025

Low stratus and dense fog continue this morning with dense fog advisory in effect for the southeast until 9AM this morning. VFR will prevail through the day today, then this evening storms push in from the west along with MVFR ceilings. In the wake of the front, low stratus and fog could develop yet again tomorrow morning./SAS/

PRELIMINARY POINT TEMPS/POPS

Jackson 77 64 77 51 / 10 80 90 20 Meridian 77 60 78 52 / 0 60 90 50 Vicksburg 78 64 77 51 / 50 90 70 10 Hattiesburg 82 65 83 56 / 0 40 80 50 Natchez 80 64 78 52 / 40 80 80 20 Greenville 72 62 73 48 / 60 90 40 10 Greenwood 74 62 75 48 / 30 90 60 10

JAN WATCHES/WARNINGS/ADVISORIES

MS...Dense Fog Advisory until 9 AM CST Tuesday for MSZ054>058-062>066- 072>074.

LA...None. AR...None.