textproduct: New Orleans/Baton Rouge

KEY MESSAGES

Updated at 528 PM CST Thu Jan 22 2026

- A Winter Storm Watch is in effect for southwest Mississippi and a portion of southeast Louisiana. A freezing rain event may impact the northern tier of the forecast area, mainly in southwest Mississippi and the Felicianas in southeast Louisiana late Saturday night into early Sunday morning. The chance of accumulating ice in this area has decreased to 20-30% this morning. Areas along the I-12 corridor west of I-55 have a 10-20% chance of ice accumulation. Icing across the Northshore, Southshore, and coastal MS is unlikely at this point (0-5% chance).

- After the threat of freezing rain, the cold Arctic airmass brings coldest air of this winter season with lows in the upper teens in northern portions of the forecast area to near freezing down to Grand Isle. This is basically Sunday morning through Tuesday morning. Cold weather headlines will likely be needed.

- Near gale force wind conditions are expected to impact the coastal waters on Sunday and Monday. These strong winds will create hazardous boating conditions in the coastal waters.

LONG TERM

(Sunday through Wednesday night) Issued at 1200 PM CST Thu Jan 22 2026

Sunday will be the most interesting day of the long term period as another surface low forms along the front in the northwest Gulf and quickly transits through the area late Sunday morning into early Sunday afternoon. A very large temperature gradient will be in place as highs behind the front only warm into the low to mid 40s, but highs ahead of the front climb into the upper 60s and lower 70s. These higher temperatures will be generally east of a Houma to New Orleans to Picayune line, and this is the area of greatest concern for surface based thunderstorms to develop between 15z and 21z on Sunday. A review of model soundings indicates that a modest degree of instability will be in place with MLCAPE of 500 to 800 J/KG over this time period. Shear parameters will be very high. 0-6 KM bulk shear will approach 60 knots and 0-3 KM storm relative helicity will range from 200 to 300 M2/S2 in coastal Louisiana, coastal Mississippi, and the offshore waters. This high shear and low CAPE scenario would favor the development of some mini-supercells capable of producing hail and a few tornadoes over this short time period. The threat will quickly end after 21z as the strong arctic cold front sweeps offshore and temperatures begin to plunge. Further to the west, temperatures will peak in the morning hours before falling through the afternoon and evening. Fortunately, the moisture will also quickly depart over this period of time, so the threat of rain transitioning back to either freezing rain or sleet at the tail end of the event is very low. By Sunday evening, any lingering rain should be confined to the offshore waters.

The arctic airmass will then be the main story as it settles over the entire Gulf South. These will be the coldest temperatures of the winter with lows plunging into the teens and 20s across the entire forecast area. These hard freeze conditions will impact both the north and southshore, and wind chills in the single digits and teens will support extreme cold warnings for the entire area Sunday night through Tuesday morning. Highs on Monday will struggle to climb into the upper 30s and lower 40s beneath full sunshine due to the strength of the arctic airmass over the region. Lows will once again cool into the teens and 20s Tuesday night with bitter wind chills continuing. The heart of the arctic air will finally begin to depart on Tuesday, and a gradual moderation of temperatures can be expected. Highs will warm into the 40s across the area Tuesday afternoon and lows will be about 10 degrees warmer with readings in the upper 20s north of I-10 and the low to mid 30s south of I-10.

Wednesday, zonal flow will once again be in place in the mid and upper levels and weak onshore flow will redevelop as the surface high over the region shifts to the east. Temperatures will climb into the 50s during the day, and a weak shortwave sliding through the area will bring increased cloud cover and possibly an isolated shower or two the area in the afternoon. The onshore flow will continue to push moisture into the region Wednesday night with lows staying above freezing.

AVIATION

(00Z TAFS) Issued at 528 PM CST Thu Jan 22 2026

Low VFR to MVFR ceilings will prevail for a few more hours before dropping into IFR or lower overnight due to both low ceilings and potentially visibilities due to fog. There's a low chance of some showers during the afternoon hours for terminals south of I-12 so left in some PROB30s. Once we get into tomorrow morning, visibility will not be a major concern. Ceilings will improve slightly to MVFR during the day.

MARINE

Issued at 1200 PM CST Thu Jan 22 2026

Lingering fog over the lake this morning will begin to lift in the next 1 to 2 hours. However, conditions remain favorable for another round of dense sea fog to develop over the nearshore waters and lakes tonight into tomorrow morning, and a dense fog advisory will be in effect for that threat.

Beyond the fog concerns, light southerly winds of 5 to 10 knots will continue into tonight. However, a weak front will shift winds to the east and east-northeast tomorrow. Wind speeds will also increase to 15 to 20 knots resulting in some exercise caution conditions. A low pressure system will approach on Saturday, and this will cause winds to shift back to the south and increase further into small craft advisory range. As the low pulls away Sunday afternoon, a strong cold front will push through. Winds will shift to the northwest and north and wind speeds could further increase to near gale force Sunday night into Monday. As high pressure builds in Monday night into Tuesday, the northerly winds will gradually decrease, but small craft advisory conditions will persist.

LIX WATCHES/WARNINGS/ADVISORIES

LA...Winter Storm Watch from late Saturday night through Sunday afternoon for LAZ034>037-039-046>048-071-083.

GM...Dense Fog Advisory until 9 AM CST Friday for GMZ530-532-534-536- 538-550-552-555-557.

MS...Winter Storm Watch from late Saturday night through Sunday afternoon for MSZ068>071.

GM...Dense Fog Advisory until 9 AM CST Friday for GMZ532-534-536-538- 550-552-555-557.