716 FXUS64 KMOB 111003 AFDMOB Area Forecast Discussion National Weather Service Mobile AL 403 AM CST Thu Mar 11 2021 .NEAR TERM UPDATE /Now Through Friday/...An upper level ridge of high pressure will continue to strengthen across the southwestern Gulf of Mexico and Bay of Campeche vicinity late tonight into Thursday and will gradually expand across much of the Gulf through Friday afternoon. Our forecast area will remain on the northern periphery of the building upper level ridge axis through the end of the week. Short range model guidance continues to show plentiful deep layer dry air and subsidence under the building ridge aloft through Friday, and we will maintain a dry forecast with POPs near zero. Little change in the surface pattern is expected through the end of the week. A surface ridge of high pressure will continue to extend westward from the western Atlantic through the north central Gulf Coast region, maintaining a persistent southeasterly to southerly flow across our forecast area Thursday and Friday. Low level moisture will be greatest across southeast MS, southwest AL, and a portion of the western FL panhandle where another decent afternoon cumulus field may once again develop both days, in addition to periodic high cloudiness streaming overhead. A shallow moist layer near the surface, dry air in the mid levels, and light surface winds will be favorable for the development of fog across much of the region late Thursday night into early Friday morning. We will likely need to monitor for the potential of some dense fog formation across a good portion of southwest and south central AL, the western FL panhandle, and potentially parts of southeast MS between 3-9 AM. Highs Thursday and Friday will range in the upper 70s to lower 80s, while lows Thursday night will range from around 50 to the mid 50s over most locations. Persistent southeasterly surface flow will continue to generate higher period swell that will approach the local beaches through Saturday. These conditions will remain favorable for the development of frequent rip currents and a HIGH rip current risk continues along area beaches. /21 BB/03 && .SHORT TERM /Friday night Through Saturday night/...A broad upper ridge located over the Gulf and extending into roughly the southeastern quarter of the CONUS amplifies and narrows during the period, with the axis of the ridge extending from the eastern Gulf to across the north central Gulf states into Iowa by Saturday night. This occurs in response to a massive upper low over the southwestern states advancing gradually eastward while an upper trof pattern remains generally in place over the northeastern states and adjacent portions of the western Atlantic. A surface ridge oriented along the northern Gulf coast steadily weakens through Saturday night but otherwise maintains a light southerly surface flow over the forecast area. Subsidence associated with the upper ridge pattern will continue to maintain dry conditions over the forecast area through the period, along with warm daytime temperatures up to around 10 degrees above normal, while the southerly flow helps keep overnight lows mild and likewise up to around 10 degrees above normal. Overnight fog development is possible each night, and will need to monitor for dense fog development in some locations. Lows Friday night range from the lower 50s inland to the mid 50s at the coast, then for Saturday night lows range from the mid 50s inland to the upper 50s at the coast. Highs on Saturday range from the mid 70s at the immediate coast to 80-85 well inland. A high risk of rip currents continues through the period. /29 && .EXTENDED TERM /Sunday Through Wednesday/...The extended term will begin as upper ridging over the southeast CONUS gives way to an incoming upper cutoff low from the Desert Southwest. Model guidance shows this cutoff low weakening as it traverses the upper Mississippi Valley on Monday. Meanwhile, another shortwave will be right on its heels, being generally over the central Plains by midweek, although there is a fair amount of model disagreement by this time. The GFS is about a day ahead of the ECMWF with this shortwave through the central CONUS, with it then progressing to the northwest over the upper Mississippi Valley by Thursday morning. The ECMWF shows the shortwave amplifying and moving more eastward during this time. At the surface, a low pressure system will traverse the central CONUS through Tuesday morning. A cold front associated with this system will move east over the ArkLaTex Monday and approach the Deep South by Tuesday morning, although, this front looks to slow down and weaken by this time. Another low pressure system will then develop over Texas by midweek, with a cold front on our doorstep by Thursday morning. The aforementioned pattern will lead to unsettled conditions for the northern Gulf coast through much of the extended. Southerly flow will also keep temperatures and moisture up through at least midweek. Chance PoPs are expected to begin Sunday night into Monday and persist through early next week, along with the potential for thunderstorms during the day Monday and Tuesday. Did not stray too far from the blended solution in regards to PoPs for midweek onward due to model discrepancies. Also included the possibility of thunderstorms Wednesday during the day. However, timing and evolution of this second system will be monitored with future model runs for better agreement. High temperatures will generally stay in the 70s through midweek due to persistent southerly flow and moisture. Lows are expected to be in the lower 60s Sunday night then be slightly cooler Monday and Tuesday nights, in the mid 50s to around 60 degrees. /26 && .MARINE...Moderate to occasionally strong southwesterly flow will persist into the weekend. Seas will slowly increase into the weekend. No current marine hazards expected. BB/03 && .MOB WATCHES/WARNINGS/ADVISORIES... AL...High Rip Current Risk through Sunday evening for ALZ265-266. FL...High Rip Current Risk through Sunday evening for FLZ202-204-206. MS...None. GM...None. && $$ This product is also available on the web at: http://weather.gov/mob