textproduct: Jackson

KEY MESSAGES

- Widespread showers and thunderstorms with potential for an isolated severe storm and locally heavy rainfall will continue across portions of south and east Mississippi today, with less coverage of rain across the remainder of the area.

- A storm system with locally heavy rain and some stronger storms remain a concern late Monday into Tuesday

MESOSCALE UPDATE

Issued at 850 AM CST Fri Nov 21 2025

An expansive shield of rain with embedded convective elements bloomed across south and east MS early this morning and continues to spread across the region at this time. Lightning has been most prevalent along the fringes of this rain shield, mainly south of I-20 where a plume of weak to moderate instability and sufficient deep shear is providing a more supportive environment for updrafts.

The key forecast question of the day will be how much recovery can occur in the areas where instability is being limited right now. An expansive low stratus deck encompasses essentially the entire area at this time with widespread rain. While this will limit destabilization during much of the day, a southerly feed of rich low level moisture will help offset this somewhat, especially along the outer extent of the rain shield, along with more potential for breaks in the clouds by the afternoon. Where greater instability is able to develop, there will be potential for a few storms to become strong to severe. Damaging wind gusts would be the primary hazard. Based on the current radar picture and high res guidance, this would seem to favor south MS into the I-59 corridor. Farther north and west, the stabilizing influence of the low stratus deck and rain appear likely to limit this threat through much of the day. Locally heavy rainfall is also possible mainly in south/east MS, with 2-4" possible in a reasonable worst case scenario, but even this should not be enough for any substantial flooding issues.

Otherwise, the clouds and rain are having an impact on temperatures as well, and forecast highs and hourly temps have been tweaked down in some areas based on current trends. There does seem to be some better opportunity for breaks in the clouds by this afternoon along and west of the MS River, so recovery to temps in the 80s would be most likely in those areas and across south MS. /DL/

DISCUSSION

Issued at 253 AM CST Fri Nov 21 2025

Through mid to late next week...

Through this weekend (Through Sunday): Synoptic analysis and water vapor imagery this morning indicate shortwave across the Central Plains ejecting to the northeast. Surface pattern indicate around 1010mb broad surface low in southern KS to northern OK. Frontal zone has lifted northward, with shortwave/surface low slowly sliding eastward into Saturday. Moist advection at the surface (low to mid 60s dewpoints climbing to upper 60s to low 70s into the afternoon hours) and aloft (PWs climbing to 1.5-1.8 inches) combined with broad jet dynamics/ascent will increase rain and storm coverage to more scattered to widespread by the mid-morning to afternoon hours. There should be a cluster of storms in eastern Louisiana, as indicated by developing showers north of Baton Rouge area, that lifts northward and becomes more the dominant feature. There remains decent shear (20-40kts in the 0-3km to 0-6km layer, respectively) and in conjunction with some destabilization, some stronger storms and isolated severe storm can't be fully ruled out. SPC added an earlier Marginal risk area and will advertise for brief gusty storms from mid morning through afternoon hours. There could be some locally heavy rainfall, generally around an inch, but localized +2 inch totals can't be fully ruled out. There shouldn't be flooding concerns due to limited residence time and recent persistent dryness.

Prior to frontal passage, rain chances will persist through weak frontal convergence into the start of the weekend early Saturday. Seasonably warm conditions are expected both Friday and Saturday, with morning lows (18-24F above) and highs (10-16F above). Record warm temperatures (highs and lows) are possible during this period. Front will carve through the area early Saturday, driving a 1020- 1024mb surface high out of the central Plains to Mid South by late weekend into Sunday. PWs will fall to around half an inch and combined with shortwave ridging building through, drier conditions and less seasonable warmth is expected late weekend on Sunday.

Next week (Monday-Thursday): As shortwave ridge builds eastward to start the work week, a more potent cold core low aloft will be moving out of the Intermountain West and into the Central Plains. Sharp jet energy (75-115kt jet in the 500mb to 300mb layers) will swing across the Plains and into the Mid West to Great Lakes by early week. This increased jet dynamics/ascent will develop a more potent surface 1004-1008mb low across the Central Plains and drive a stronger cold front late Monday night into Tuesday. Strong southwesterly shear (35-50kts) will set up but remain mostly line- parallel. This will help drive dewpoints back up into the 62-67F degree range along and south of Interstate 20. With southwesterly mean bulk shear, limited residence time of warm sector and less favorable timing generally closer to the diurnal minimum, this looks to be short duration potential. However, can't fully rule out some low end (non-zero) strong to severe potential Monday night into Tuesday. There are some differences in amplitude of the filling closed low aloft/shortwave, with the Euro slightly digging a little more. This will affect how long rain chances persist another 24-36 hours. Rain totals will be sufficient, around 1.5 to 2 inches (locally higher in convection or areas of training in line-parallel storms). However, recent dryness and limited preceding rain accumulation Friday limits confidence and holding off in HWO. Synoptic discontinuity exists, with with Euro more progressive and amplitude situated further north but stronger ascent and eastward propagation, while GFS more sharp cold core over the Great Lakes/northern Plains by midweek and continued southwesterly flow and rain chances later Wednesday. Blended rain chances look on track but may be a touch too slow. Regardless, 1028-1030mb surface high will bring drier (PWs around quarter inch) and seasonably cooler conditions into late next week. /DC/

AVIATION

(12Z TAFS) Issued at 529 AM CST Fri Nov 21 2025

Conditions are kind of all over the place this morning with low ceilings and low visibility across the southeast. Rain showers moving into the area seem to be leading to gradual improvement in visibilities and ceiling, still expect these to remain a challenge for a while longer. Conditions should improve mid to late morning as ceilings and visibility lift to VFR. Intermittent showers should continue throughout the day. Ceilings become a problem again tonight with low stratus again persisting into the early morning hours./SAS/

PRELIMINARY POINT TEMPS/POPS

Jackson 76 64 78 52 / 90 20 10 0 Meridian 73 63 79 50 / 90 30 10 0 Vicksburg 79 64 78 52 / 70 20 10 0 Hattiesburg 80 65 83 53 / 80 20 10 0 Natchez 80 64 79 52 / 80 20 10 0 Greenville 79 60 74 50 / 30 30 0 0 Greenwood 76 62 76 50 / 50 40 10 0

JAN WATCHES/WARNINGS/ADVISORIES

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