829 FXUS64 KLIX 081707 AFDLIX Area Forecast Discussion National Weather Service New Orleans LA 1207 PM CDT Sun Jun 8 2025 ...New AVIATION... .SHORT TERM... (Today through Monday) Issued at 330 AM CDT Sun Jun 8 2025 Upper ridge axis extended southward from New Mexico into Mexico this morning. Upper troughs were noted over the Canadian Prairie Provinces into the western Great Lakes, as well as off the southern California coast. There were 3 separate complexes of thunderstorms to our north...1) over Alabama and eastern Mississippi, 2) over the Arklatex area, and 3) over the Texas Panhandle. Locally, skies were clear to partly cloudy at 3 AM CDT with temperatures ranging from the mid 70s to lower 80s, with dew points in the mid 70s. Any thunderstorms were well to our north, north of Interstate 20. Dual concerns in the forecast today. One is the potential for severe weather this afternoon through Monday, but primarily during the overnight hours tonight. The second concern is heat-related, with a Heat Advisory already in effect for later today for the southeast Louisiana parishes bordering on Lake Pontchartrain. The Alabama-eastern Mississippi cluster of storms is already passing northeast of the area and isn't a factor in the forecast. However, the other two complexes will be. The upper level flow is northwesterly across the area and is expected to carry the Arklatex complex toward the area later this morning and this afternoon. Most of the convection allowing models show this area of storms weakening as it approaches the area this afternoon. CAPE values are in the 2000-3000 (locally higher) J/kg range, lapse rates in the 6.5-7.5 C/km range and DCAPE values in excess of 1000, so storms would have at least some potential for strong winds. Even if the storms don't quite make it into the area, they are expected to lay out a boundary somewhere close to the northwest portion of our area this afternoon. This will provide a pathway for the complex currently over the Texas Panhandle area to follow later tonight into Monday morning as it weakens. This will reinforce a boundary to focus potential development later in the day on Monday. Of the 3 rounds, the last one may provide the best opportunity to produce severe weather, with the greatest threat from about Interstate 55 eastward north of Lake Pontchartrain. We'll also need to monitor the threat for excessive rainfall for the potential for multiple rounds to track over the same area, wherever the boundary ends up. With precipitable water values near 1.8 inches, a quick 1-2 inches is possible with each round, possibly producing runoff issues in urban areas. With highs in the lower and middle 90s expected this afternoon, heat index values in the 105 to 110 range are possible in the parishes surrounding Lake Pontchartrain. Elsewhere, a few spots may reach those values, but confidence is lower there. Won't rule out the need for an additional advisory on Monday, depending on how the precipitation and cloud scenarios play out today and tonight. && .LONG TERM... (Monday night through Saturday) Issued at 330 AM CDT Sun Jun 8 2025 Tuesday and potentially Wednesday could be pretty similar to Monday when it comes to convective development in zonal to northwesterly upper flow across the area. Scattered to numerous showers and storms will be possible both days, especially during the afternoon and early evening hours, with a few possibly on the strong side. As we get toward the end of the week, ridging is expected to build over Florida with troughing over Texas. This should keep the most favorable conditions for storm development off to the west of the area for Thursday into Saturday, but there will be more than sufficient moisture available for at least scattered development each day. Those should be a bit more of what we think of as a "normal" summer day with thunderstorms. Temperature ranges shouldn't be unusual for mid June, with highs within a few degrees of 90 and lows in the 70s. No significant adjustments made to NBM temperatures. && .AVIATION... (18Z TAFS) Issued at 1204 PM CDT Sun Jun 8 2025 VFR conditions prevail at all area airports. Conditions at most area airports will drop to MVFR tomorrow morning due to low ceilings from increasing cloud cover. Late afternoon storms today with an approaching system will cause some conditions that warrant TEMPO groups for periods of low ceilings and visibilities, mainly at BTR and MCB. Additionally, patchy fog will cause lower ceilings and visibilities for a few hours around daybreak at MCB. MSW && .MARINE... Issued at 330 AM CDT Sun Jun 8 2025 Not surprisingly for June, the main concerns for marine operations will be the threat of thunderstorms, especially from Monday onward. Localized hazardous wind and sea conditions will be possible with storms. Overall, winds should maintain an onshore component through the week, and could briefly reach or slightly exceed 15 knots, especially over the eastern waters during the evening hours each day. && .PRELIMINARY POINT TEMPS/POPS... MCB 72 89 70 86 / 50 80 70 80 BTR 76 92 75 88 / 30 60 60 90 ASD 74 92 72 88 / 30 50 50 90 MSY 78 94 77 90 / 20 40 40 90 GPT 77 91 74 87 / 50 60 70 90 PQL 75 90 72 88 / 60 60 70 90 && .LIX WATCHES/WARNINGS/ADVISORIES... LA...Heat Advisory until 7 PM CDT this evening for LAZ046>048-057-058- 060-064-076>090. GM...None. MS...None. GM...None. && $$ SHORT TERM...RW LONG TERM....RW AVIATION...MSW MARINE...RW