textproduct: Jackson

KEY MESSAGES

- Dry and very warm air today support limited fire danger threat. - Rain chances return by late week with widespread rainfall expected this weekend before cooler and drier conditions into middle of next week.

MESOSCALE UPDATE

Issued at 1242 PM CDT Wed Sep 30 2026

Rest of today into tonight...

Last day of quiet and warm weather is on tap across the region. 589-590DM mid level ridge axis is centered across the area but becoming squeezed in between the stout trough over the Desert Southwest and upper low over the northeast Gulf. At the surface, southerly return flow and increased gradient from high pressure to the east and remnant low pressure over the north-central Plains is aiding in some uptick in gradient winds. This is pattern supports one last day of deep dry air and efficient mixing, especially in north-central to northeast MS and extreme southeast AR. In these areas, winds are a touch more breezy and humidity will drop down into the mid to upper 30s percent range (30-35%), so a limited fire danger threat still exists across these areas. Take precautions with any outdoor burning and heed any local burn bans. Highs and lows will be seasonably warm, some 8-15F above (91-95F for highs and 66-72F for lows). There are some dense fog probs overnight in the HREF and REFS but confidence over dry ground, even with moist advection, lowers confidence of dense fog. In this advection scheme, coastal dewpoints are currently in the low to mid 70s (72-74F), so there could be some crossover temps approaching the 3-4F range. Added patchy fog but will hold off introduction in HWO graphics. Updates were shipped out earlier. /DC/

DISCUSSION

Issued at 1242 PM CDT Wed Sep 30 2026

Thursday through early next week (Tuesday)...

Thursday into weekend: A change to a wetter weather pattern is still anticipated for late this week into the weekend as the previously mentioned trough helps to induce increased southerly flow and moisture transport, with deep level moisture eventually increasing to anomalous levels over the forecast area (e.g., precipitable water 2 to 3 SD positive anomalies). Given the prolonged presence of weak synoptic scale ascent related to the subtle but persistent upper jet influence and modest low level moisture convergence, the forecast reflects a long duration of high rain chances in the Friday through Sunday time frame.

While prospects for a wet weekend remain high, the potential impacts related to this upcoming wet weather pattern are quite uncertain, especially when considering that model guidance has continued to shift weaker with the upper trough presence and stronger with the southeast CONUS subtropical high center. Because of this, heavier QPF has shifted some closer to the coast and brings into question the potential for heavier rainfall. Regardless of the heavy rain potential, given how dry it has been recently, the rain that does fall would be highly beneficial in most cases.

Next week: Looking ahead, drier and somewhat cooler air should surge into the forecast area as northwest flow aloft becomes the primary driver for our weather. /EC/

AVIATION

(18Z TAFS) Issued at 1242 PM CDT Wed Sep 30 2026

VFR flight conditions with south/southeast winds near 8-10 kts will prevail through the period. Patchy fog may be possible between 10- 14Z Thursday, reducing flight condition to MVFR/possible IFR at affected sites. After 15Z Thursday, flight conditions will return to VFR. /SW/

PRELIMINARY POINT TEMPS/POPS

Jackson 93 70 92 70 / 0 0 40 10 Meridian 92 68 91 68 / 0 0 40 10 Vicksburg 93 70 93 70 / 0 0 30 20 Hattiesburg 93 70 91 70 / 0 0 60 20 Natchez 94 71 93 70 / 0 0 40 10 Greenville 95 70 94 71 / 0 0 10 30 Greenwood 95 69 94 70 / 0 0 20 10

JAN WATCHES/WARNINGS/ADVISORIES

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