textproduct: New Orleans/Baton Rouge

KEY MESSAGES

Updated at 625 PM CDT Mon Apr 13 2026

- Sun and temperature related health risks will be the primary concern with sunny skies and warm temperatures on tap through much of the week. Make sure to use sunscreen and drink plenty of water if you intend to be outside enjoying activities like sports and festivals.

- Light fog development remains possible each morning particularly near water bodies. Chances for higher coverage of moderate to dense fog exists Tuesday and Wednesday morning, but forecast confidence is low at this time.

SHORT TERM

(Now through Wednesday) Issued at 1130 AM CDT Mon Apr 13 2026

The upcoming days will be largely driven by persistent southeast flow on the southwest flank of a strong surface high centered near Bermuda. Temperatures will be strongly driven by diurnal forces and dew point temperatures in the low to mid 60s each day. The recent uptick in low-level moisture as noted by the 1200 UTC LIX sounding this morning does indicate that there will be sufficient moisture for fog development though our positioning away from the center of the surface high will make it more difficult for us to decouple and calm down at the surface, sufficient for fog development. This creates uncertainty in density and coverage of fog development tonight and Tuesday night. SREF/HREF probabilities indicate a medium chance for moderate to dense fog (3 miles to 1/2 mile) Tuesday morning, predominantly focused before and at sunrise, but another forecast cycle is needed to monitor trends and boost forecast confidence of any patch dense fog develop, particularly for southern MS and adjacent parishes.

Days will largely start out with patchy, light to moderate fog particularly farther inland in areas of southern MS and Atchafalaya Basin which will quickly dissipate after sunrise. Once any fog clears, a cu field will gradually develop throughout the peak daytime heating hours. A few of these cu may tower a little taller and a stray shower cannot be ruled out. Anomalously warm temperatures aloft due to strong mid-upper ridging in the SE CONUS will also aid in rapid warming of temperatures into the mid 80s away from the immediate coast, around 5 to 10 degrees above normal.

LONG TERM

(Wednesday night through Sunday) Issued at 1130 AM CDT Mon Apr 13 2026

A toasty end of the work week appears to be ahead with temperatures continuing to trend warmer Thursday through Saturday. The only caveat for Thursday being that the nose of the upper ridge will be eroded some by the passage of a weak shortwave trough across the Mid Mississippi River Valley. Even still, probabilities of temperatures reaching 90F near and northwest of Baton Rouge as well as the Pearl River Basin near and north of Bogalusa are 50-70% for Friday and Saturday. If 90F is reached, this would be about a month earlier than the average first 90F day for Baton Rouge (BTR).

Another stronger trough will dig across the SW CONUS before ejecting and lifting through the central CONUS. This will generate a strong mid-latitude cyclone that will lift through the Great Lakes and help to drive colder air and a strong surface high pressure through the Mississippi River Valley this weekend. Uncertainty exists as it pertains to where this trough and surface cyclone eject as that longitude will matter regarding how strong any frontal system will be as it approaches the Gulf Coast around the Sunday timeframe. This would be our best bet at reprieve from the spring heat as well as supply us with our highest chance for rain in the forecast period.

AVIATION

(00Z TAFS) Issued at 625 PM CDT Mon Apr 13 2026

All terminals VFR at forecast ussuance time. There were some scattered cumulus clouds with most bases above FL030. Most of these should dissipate with sunset. With southeast surface flow continuing, we'll probably see a few patches of lower cloud during the evening and overnight hours, primarily MVFR. Can't rule out radiation fog entirely, as we won't have the high clouds we had last night. But dew points are in the same range as last night (60-65F), and there wasn't a lot of development, even in areas that didn't have the high clouds. If any fog does develop, it probably won't be much before 10z, and should mix out prior to 14z. Beyond that point, most likely just some fluffy cumulus clouds. Cloud bases by midday probably around FL040.

MARINE

Issued at 1130 AM CDT Mon Apr 13 2026

Strong surface high pressure from the northeast gulf into the Atlantic continues to produce a moderate easterly to southeasterly fetch over the northern Gulf. Winds have eased to just under 15 kt and should remain there throughout this week. At this time, the onshore fetch appears to be too weak to cause minor coastal flooding, but we will continue to monitor tidal trends as we approach the spring tide phase. Onshore flow will continue through at least Saturday with the potential for offshore flow from a cold front coming on Sunday and into early next week.

LIX WATCHES/WARNINGS/ADVISORIES

LA...None. GM...None. MS...None. GM...None.