Area Forecast Discussion
Issued by NWS New Orleans/Baton Rouge, LA
Issued by NWS New Orleans/Baton Rouge, LA
641 FXUS64 KLIX 012348 AFDLIX Area Forecast Discussion National Weather Service New Orleans LA 648 PM CDT Tue Jul 1 2025 ...New AVIATION... .SHORT TERM... (This evening through Thursday night) Issued at 151 PM CDT Tue Jul 1 2025 A fairly potent trough digging into the Midwest today will continue to deepen across the eastern seaboard tonight into tomorrow. As this occurs, a front will strengthen and begin to surge to the south. This frontal boundary will pass through the forecast area during the day tomorrow before stalling just offshore Wednesday night into Thursday. In the wake of this frontal passage, a much drier and more stable airmass will advect into the area. PWATS will fall from around 2 inches, or between the 75th and 90th percentile tomorrow, to around 1.25 to 1.5 inches on Thursday. These values are in the 10th to 25th percentile for this time of year. Before this drying occurs, another round of scattered to numerous showers and thunderstorms will fire up both in advance of an along the frontal boundary tomorrow. Highly efficient rainfall processes will support rainfall rates of up to 2 inches per hour, so some localized flooding concerns could arise if storms move over poorly drained areas. On Thursday, the strengthening upper level ridge axis will be the primary contributor to lower PoP as increasing subsidence aloft promotes both warming and drying in the mid and upper levels of the atmosphere. This drying and warming aloft will lead to the development of a strong mid-level capping inversion, and this will effectively limit any deeper convective updrafts from forming over most of the forecast area Thursday into Thursday night. At most, some isolated convection could develop near the stalled frontal boundary along the immediate coast of Louisiana Thursday afternoon due to increased low level convergence and forcing. Temperatures will also warm at the surface as the airmass dries out with readings climbing into the low to mid 90s. Fortunately, the drier air aloft will mix into the boundary layer and help to keep max heat index values between 100 and 105 degrees. && .LONG TERM... (Friday through Monday night) Issued at 151 PM CDT Tue Jul 1 2025 The deep layer ridge axis and resultant subsidence will remain in firm control of the forecast area on Friday and Saturday. PWATS will remain between the 10th and 25th percentile for this time of year and cloud development will be suppressed as a strong mid- level inversion remains in place. The end result will be a largely hot and dry stretch of weather. Temperatures both days will warm into the mid to upper 90s and heat index values will approach 105 degrees. Fortunately, heat advisory conditions look less likely as the drier air aloft mixes into the boundary layer and allows RH values to fall to between 40 and 50 percent. Rain chances will be very limited with only an isolated shower or storm possible along the seabreeze boundary both days. Sunday will be a day of transition as the ridge shifts to the west and an inverted trough begins to move in from the east. Increasing lift and moisture will allow for a bit more convective coverage on Sunday, and overall conditions will be very normal for early July in the region. Precipitable water values will be near the median for this time of year, and PoP will also be near average at around 30 to 40 percent in the afternoon hours on Sunday. The increase in cloud development and convective activity will allow for slightly cooler highs in the low to mid 90s, but the increase in humidity will keep heat indices at around 105 degrees. On Monday, the inverted trough should close off into an upper level low that will be parked over the area. PWATS will increase to around 1.8 inches or around the 75th percentile for this time of year, and this increase in moisture in tandem with increased forcing aloft will allow for more numerous showers and thunderstorms during peak heating hours in the late morning and afternoon hours. Temperatures will also be near average and heat index values will remain near 105 degrees outside of brief cool downs from the rain. && .AVIATION... (00Z TAFS) Issued at 645 PM CDT Tue Jul 1 2025 Area of convection that has been affecting KGPT is dissipating over the Gulf, but another area of storms between KJAN and KHBG is diving southeastward and could affect multiple terminals prior to 03z, and will use TEMPO to handle those. One final round of TSRA possible around midday on Wednesday as frontal boundary moves into the area. Beyond about 21z tomorrow, a period of several days should onset without TSRA. && .MARINE... Issued at 151 PM CDT Tue Jul 1 2025 West winds of 10 to 15 knots will persist through Wednesday night as a high remains parked over the northern Gulf. The high will shift to the west on Thursday, and winds will shift to the northwest as a weak front slides through the waters. This offshore flow will persist through Friday. Over the weekend, winds will shift back to the east and southeast a broad surface high centered over the eastern seaboard expands to the west. Overall, winds and seas will remain well below any advisory criteria. However, locally gusty winds and higher seas will occur with any thunderstorm activity that forms through the forecast period. && .PRELIMINARY POINT TEMPS/POPS... MCB 72 91 71 93 / 40 20 10 10 BTR 76 93 75 94 / 30 40 20 20 ASD 75 92 73 94 / 40 50 10 10 MSY 78 92 78 93 / 30 50 30 20 GPT 75 90 75 92 / 50 50 20 10 PQL 73 90 73 93 / 50 50 20 10 && .LIX WATCHES/WARNINGS/ADVISORIES... LA...None. GM...None. MS...None. GM...None. && $$ SHORT TERM...PG LONG TERM....PG AVIATION...RW MARINE...PG