083 FXUS64 KMOB 181654 AAA AFDMOB Area Forecast Discussion...UPDATED National Weather Service Mobile AL 1054 AM CST Sun Feb 18 2018 .DISCUSSION...See updated information for land and marine areas below. && .UPDATE...We have updated the forecast to remove fog headlines and mention of fog in the products as area observations show visibility has rapidly improved across the region. Mostly cloudy skies should prevail over inland areas today, with some breaks in the clouds expected over southern portions of the region. We did leave a slight chance of light rain over far northern sections of the area through this afternoon, as this region will be on the southern fringe of weak ascent associated with a mid level shortwave impulse and also ahead of a northward moving warm front/surface boundary. Any associated rainfall amounts should be very light. Above normal temperatures continue into the afternoon with highs mostly in the 70s appearing to be on track. /21 && .MARINE...We allowed the Dense Marine Fog Advisory to expire on schedule at 9 AM CST, though we still left mention of patchy fog along area bays, sounds and nearshore waters through the late morning hours. The latest high resolution and short term guidance indicates another round of marine fog will likely be of impact again this evening through early Monday morning, and will assess this potential for the afternoon marine forecast package. /21 && .PREV DISCUSSION... /issued 557 AM CST Sun Feb 18 2018/ DISCUSSION...Updated for latest aviation discussion below. AVIATION... 12Z issuance...Will begin with IFR to MVFR ceilings over much of the area along with some VLIFR conditions in low ceilings and fog mainly over the western Florida panhandle. Conditions improve to primarily VFR ceilings later this morning then there is the potential for IFR conditions to redevelop again late tonight. Light northerly winds over the area switch to a southeast direction by midday with light southerly winds continuing overnight. /29 PREV DISCUSSION... /issued 442 AM CST Sun Feb 18 2018/ NEAR TERM /Now Through Sunday night/...The axis of an upper ridge over the central Gulf shifts closer to the Gulf coast during the period resulting in modest deep layer subsidence shifting into the forecast area. A weak cold front currently moving southward through the coastal counties is expected to have moved into the marine area by the beginning of the period. A combination of low and mid cloudiness along with northerly winds of 5 to 10 knots in the wake of the front has acted to either dissipate or significantly limit fog over most of the area except for coastal Baldwin county and part of the western Florida panhandle. Considering current observations and trends, will keep the Dense Fog Advisory in place for coastal Baldwin county and the coastal portion of the western Florida panhandle but cancel elsewhere. The weak front returns northward into the central portion of the forecast area later today then exits north of the forecast area tonight. Will have small pops well inland today as daytime heating and the weak front result in a potential for isolated showers, while modest subsidence associated with the upper ridge should suppress convection elsewhere. Dry conditions follow for tonight and patchy fog development is possible for the entire area late tonight. /29 SHORT TERM /Monday Through Tuesday night/...An upper-level ridge builds over the western Atlantic and southeastern U.S. to begin the short term, shifting flow over the local area from zonal to more southwesterly as an upper trough simultaneously deepens over the western CONUS. At the surface, high pressure builds into the western Atlantic and eastern Gulf, re-establishing warm and moist onshore flow across the region. With the return of this pattern comes increasing rain chances, initially over southeast Mississippi Monday afternoon and gradually spreading over the remainder of the area by Tuesday. Only minimal instability is expected to develop this quickly after the return of onshore flow, with much of it remaining offshore. Thus, while a rumble or two of thunder cannot be ruled out near the coast, activity should remain generally limited to scattered light showers. Have continued to lean on the warm side of guidance for high temperatures through the short term given the combination of an anomalous upper ridge and a warm and moist onshore surface flow. Highs will approach (or possibly even surpass) record levels both Monday and Tuesday afternoons, reaching the upper 70s to lower 80s across the area. /49 LONG TERM /Wednesday Through Saturday/...This unseasonably warm and moist pattern, one more characteristic of Spring and not mid- February, will keep temperatures near record highs and rain chances elevated throughout the upcoming week. The broad upper- level troughing over the western CONUS finally begins to flatten the ridge over the western Atlantic, pushing it south towards the end of this week and into next weekend. This shift allows a cold front to push southeast across the Great Plains and into the lower Mississippi River Valley, ultimately stalling somewhere northwest of our area by late Thursday. Best rain chances throughout the long term will be over our interior southeast Mississippi and southwest Alabama counties ahead of this approaching front. Models continue to indicate a fair amount of destabilization occurring during afternoon hours (500-1000 J/kg MLCAPE), improving our chances of seeing thunderstorms mix in with showers as well. The front lifts back north and away from the area Friday as the western Atlantic surface high is reinforced, leading to a brief reprieve from the rain. However, the front returns (along with rain chances) by late Saturday, eventually pushing through the area as the upper ridge to our east breaks down and the pattern becomes more progressive. Much like the short term, the combination of an anomalous upper ridge and well-established onshore surface flow will result in high temperatures approaching or surpassing record levels pretty much every day this week. Highs reach the upper 70s to lower 80s each afternoon and lows only dip into the low to mid 60s each night. /49 MARINE...A weak front over the northern Gulf moves inland later this morning with light west to north winds becoming southeasterly. A light to moderate southeasterly flow continues for Monday through Thursday. Have continued with a marine dense fog advisory for the bay and near shore waters of the western Florida panhandle through early this morning, including Perdido Bay. Fog development will be possible for each following night over the bay and near shore waters through early next week. /29 && .MOB WATCHES/WARNINGS/ADVISORIES... AL...None. FL...None. MS...None. GM...None. && $$ This product is also available on the web at: http://weather.gov/mob