Area Forecast Discussion
Issued by NWS New Orleans/Baton Rouge, LA
Issued by NWS New Orleans/Baton Rouge, LA
838 FXUS64 KLIX 172314 AAA AFDLIX Area Forecast Discussion...UPDATED National Weather Service New Orleans LA 614 PM CDT Sun May 17 2026 ...NEW AVIATION... .KEY MESSAGES... Updated at 609 PM CDT Sun May 17 2026 - Isolated to scattered showers and storms will affect areas mainly west of the I-55 corridor today and Monday. A few storms may be locally strong and capable of locally heavy rainfall. - Showers and thunderstorms will spread further eastward toward the I-59 corridor Tuesday and Wednesday, with more area-wide coverage Thursday through next weekend. Some of these daily storms could become strong and/or produce locally heavy rainfall. - Temperatures are forecast to be generally near to warmer than normal through the next 7 days. && .SHORT TERM... (Now through Tuesday) Issued at 1230 PM CDT Sun May 17 2026 With high pressure centered off the east coast, southeast winds will continue to bring moisture back into the area. Dewpoints at nearly all observing sites across the region have rebounded into the low to mid 70s compared to the mid 60s yesterday and upper 50s day before. A confluent zone between the high to our east and low pressure taking shape near the four corners is currently manifesting as a broad area of clouds stretching from southern Texas through the middle Mississippi Valley. As we move later into the afternoon hours and the atmosphere continues to destabilize, expect to see at least isolated to scattered showers and storms pop up, especially west of the I-55 corridor closer to the stronger confluence. While the setup isn`t overly conducive for severe weather, lapse rates appear sufficient for hail growth in longer-lived storms that are able to take advantage of the instability. As any hail cores descend, isolated stronger wind gusts will also be possible. That being said, SPC is highlighting a marginal risk of severe weather for northwestern portions of the area, which overlaps with the higher thunderstorm chances as well. In addition to the gusty wind and hail threat, a few storms could produce locally heavy rainfall owing to the increased atmospheric moisture allowing for more efficient rainfall processes. Monday and Tuesday will see similar patterns, with the highest rain chances generally across northwestern areas and an isolated threat of stronger storms producing gusty winds and heavy rainfall. && .LONG TERM... (Wednesday through Saturday) Issued at 1230 PM CDT Sun May 17 2026 The pattern becomes even more active as we move into the latter half of the week and weekend. Increasing moisture combined with a fast-moving upper disturbance traversing the lower Mississippi Valley late Wed into Thur, then a deeper upper trough and associated cold front approaching the Mississippi valley over the weekend, will lead to more widespread daily showers and storms through the period. Significant severe weather is not anticipated at this time, but looking at model forecast soundings across the region, some of the storms each day will be capable of becoming strong and producing gusty winds. Precipitable water is forecast to be in the 1.6-1.8" range during the second half of the week and into the weekend, depending on the day and location. While these kinds of values may not seem all that high, they`re actually well above normal, sitting above the 75th percentile, and approaching the 90th percentile for this time of year. That being said, expect to see at least a localized flooding threat - especially in urban areas and other areas of poor drainage. Generally speaking, the highest rainfall totals are currently forecast across areas northwest of a line from Morgan City to Laplace to Picayune, though individual storms could easily result in localized higher totals southeast of this line as well. && .AVIATION... (00Z TAFS) Issued at 613 PM CDT Sun May 17 2026 VFR conditions through the evening looks to be reduced to MVFR overnight as low CIGs develop after midnight. A few hours after sunrise, conditions should improve to VFR conditions and this should persist through the remainder of the cycle. There is a low chance for showers and storms west of the I55 corridor Monday afternoon, but given the very isolated nature...was not confident to add PROBs for this update, but could be added in subsequent packages. (Frye) && .MARINE... Issued at 1230 PM CDT Sun May 17 2026 Onshore flow will persist as high pressure remains anchored over the western Atlantic. A tightening pressure gradient between this high and low pressure across the plains states will lead to strengthening winds, especially west of the Mississippi River. Exercise Caution headlines will remain in effect through tonight and may need to be extended into Monday. As moisture increases across the region, he chance of daily showers and storms will gradually increase, with the best chances later in the week as a weak front approaches the area. Some storms will be capable of producing locally hazardous winds and waves. && .LIX WATCHES/WARNINGS/ADVISORIES... LA...None. GM...None. MS...None. GM...None. && $$ SHORT TERM...DM LONG TERM....DM AVIATION...RDF MARINE...DM