textproduct: Jackson

KEY MESSAGES

- Areas dense fog is likely this morning along and south of Interstate 20 while patchy dense to the north; dense fog advisory is in effect.

- Roller coaster temperature swing into Sunday with morning lows below freezing across the north while struggling to rise above freezing in the northwest Delta.

- Gusty gradient winds are likely tomorrow, with potential wind chills struggling to the low to upper 20s Sunday afternoon.

- Dangerously cold temperatures are expected Sunday night with widespread wind chills into the 10 to 20 degree range.

DISCUSSION

Issued at 118 AM CST Sat Dec 13 2025

Through Friday...

This morning through tonight: Surface analysis indicates frontal zone draped across the Interstate 20 corridor, with a zone of dense fog expanding northward across the region. HREF dense fog probs (25 to 55 percent) are projected through the mid-morning hours, with duration of dense fog probs in the "Limited" and "Elevated" range in excess of 8 hours. A dense fog advisory is ongoing and remains valid. The HWO graphic was updated earlier to expand the "Limited" north of Interstate 20 corridor and add an Elevated along and to the south (corridor of the highest dense fog probs in excess of 25 percent and long duration). This is projected to lift by mid-morning hours.

Water vapor/RAP/upper air analysis this morning indicate cold core over central Canada, just north of the Great Lakes, with northwest flow continuing over the region. An eventual amplification of the synoptic and surface pattern is projected through the weekend. Stout upper jet energy (140 to 155kts) is moving out of southwest Canada and into the northern Great Lakes, High Plains to Mid West states. This will drive the overall amplified mean synoptic and surface pattern, driving a polar front into the region today and strong surface high (1035mb to 1040mb) southward out of Canada into the Plains to Mid West. For today, some increased moist convergence and deep moisture (PWs around 1.2 to 1.3 inches) will spark some shower development across the area, with the highest coverage southeast of the Delta and into the Natchez Trace corridor and southeast. This afternoon will be scattered at most (25 to 35 percent) while increased coverage through around or just after midnight (35 to 75 percent). A few rumbles of thunder can't be ruled out, but rain will be the majority of concerns. A roller coaster of temperatures will be on the way as highs peak well above normal today, some 8 to 14F above (64 to 74F) southeast of the Delta while 55F to 63F into the Delta. Strong dry subsidence and cold advection will move in tonight as the frontal zone moves toward the Gulf Coast and well into the northern Gulf by Sunday morning. Lows will be seasonably cold, falling below freezing to 5 to 10F below northwest of the Natchez Trace (24F to 33F), while to slightly seasonable to the southeast (34F to 46F). Rain will end well in advance of the cold air advection, so no concerns exist for wintry weather.

Sunday through next week (Friday): Main concerns turn to the dangerous cold projected across the area. 1040 to 1045mb arctic airmass will dive down through the Mid West and into the Appalachians through early week. This will drive arctic air, highs some 15F to 25F below normal Sunday (30F to 45F along and northwest of the Natchez Trace while struggling to reach freezing in the extreme northwest Delta). It will be a blustery period in the wake of the arctic front. Morning wind chills will fall into the teens to mid 20s by Sunday morning. Afternoon wind chills struggle to reach freezing just southeast outside of the Delta while well below freezing, into the low to upper 20s, in the Delta. Lows will be quite dangerous Monday morning, into the mid teens and low 20s (15F to 24F), with wind chills into the 10F to 20F range areawide. These cold temperatures pose a threat to people, pets, pipes and plants. Take precautions now to plan ahead of this up and down roller coaster swing of temperatures, going from a nice seasonably warm afternoon today to winter jackets in 24 to 36 hours. Make sure to have areas that you can stay warm. In addition, very strong pressure gradient/cold advection will lead to efficient mixing of gusty winds. Some could reach near or in excess of 30mph. A "Limited" in the HWO graphics will likely be needed for portions of the area.

Synoptic flow will become zonal aloft through mid to late week, with return flow of moderation and warmth through the work week. This will bring a series of larger synoptic trough and frontal systems around mid week. Global models are a little more murky on synoptic amplitude details, with Euro with a sharper trough/front and 1030mb surface high sagging southeast into the Mid West to Mid MS River Valley, while the GFS delivers a glancing blow and trough axis further north. For now, leaving blended guidance as is. There could be an opportunity for some storms around mid week and potential again into next weekend, but those details will have to be ironed out as we get closer. /DC/

AVIATION

(06Z TAFS) Issued at 1141 PM CST Fri Dec 12 2025

Dense fog and low ceilings are projected through the early morning hours for central and southern portions of the area tonight, with patchy fog elsewhere. Some light drizzle can not be ruled out with the aforementioned conditions through the morning with an increased coverage/intensity possible with daybreak. Conditions should improve rapidly with sunrise (around 14Z). /OAJ/

PRELIMINARY POINT TEMPS/POPS

Jackson 69 36 45 20 / 20 50 0 0 Meridian 67 35 45 19 / 20 70 0 0 Vicksburg 66 33 41 21 / 30 50 0 0 Hattiesburg 73 45 55 21 / 30 70 20 0 Natchez 72 38 47 22 / 30 70 10 0 Greenville 55 27 32 19 / 10 20 0 0 Greenwood 62 28 36 18 / 10 30 0 0

JAN WATCHES/WARNINGS/ADVISORIES

MS...Dense Fog Advisory until 9 AM CST this morning for MSZ043- 047>066-072>074.

LA...Dense Fog Advisory until 9 AM CST this morning for LAZ015-016- 023>026.

AR...None.