082 FXUS64 KBMX 010553 AFDBMX Area Forecast Discussion National Weather Service Birmingham AL 1153 PM CST Thu Nov 30 2017 .UPDATE... For 06Z Aviation. && .SYNOPSIS... A surface cold front extended from northern Louisiana into north- central Mississippi and was entering into the far northwest corner of Alabama at this hour. A surface trough axis extended from a weak low pressure center near Florence, Alabama and extended south-southwest to Columbus, Mississippi and extended further south-southwest to the Hattiesburg, Mississippi area. Partly cloudy to overcast skies were common across the forecast area today with light to moderate rain showers that affected much of our northern and central counties this morning and into early afternoon. Right now rain showers continue to affect portions of our southern and south-central counties. .SHORT TERM... Expect shower activity to persist across our southern and southeast counties tonight, decreasing in coverage gradually through early Friday morning. Patchy fog is expected overnight but confidence of exceeding the dense fog advisory criteria is too questionable to warrant an issuance at this time. Patchy fog may develop as early as this evening but development will be hampered by light winds that will persist overnight along with drier air that will gradually advect in from the northwest. Potential for fog looks to be greatest across our southeast counties. For the long term period, few adjustments made as the overall pattern is persisting in today's guidance. Relative weak shortwave ridging builds into the area from the south over the weekend followed by a shortwave impulse that approaches the area on Monday and Tuesday. By midweek, a long wave positively tilted trough is expected to extend across much of the central states and will approach the area. Increases in rain coverage remain on- track during the day Tuesday and persists through Wednesday and pushes southeast of the area on Thursday. Potential for freezing temperatures will exist for Thursday morning but all precipitation is expected to have exited the area before freezing temperatures are achieved. 05 .LONG TERM... Friday through Thursday. Rain-free conditions should return for Friday behind a weak front located to our south and east. Weak flow in the surface to 850mb layer will result in little advection of drier air, and low clouds could plague parts of the forecast area on Friday and Saturday. Due to uncertainty regarding cloud cover, temperatures may be rather difficult to pin down. A quasi-zonal flow pattern is expected to result in quiet and mostly dry conditions over the weekend and into Monday. However, this will not be the case beginning Monday night. Confidence is increasing regarding amplification of the jet stream and the passage of a strong cold front probably sometime on Tuesday afternoon or Tuesday night. Moisture return continues to appear significant, and this system could provide much needed rainfall to the region before a much colder airmass arrives on Wednesday. 87/Grantham && .AVIATION... 06Z TAF Discussion. Widespread dense fog has formed across central Alabama this evening. The dense fog was primarily located between I-59 and I-85. A weak cold front has brought drier air into northwest Alabama and dissipated the fog for areas just north of a KTCL- KBHM- KGAD line. This drier air will continue to sink southward overnight and expect improving conds at KTCL/KBHM by 08z and KANB/KASN/KEET by 09z or 10z. Dense fog will impact KMGM and KTOI thru 14z. Even after the fog burns off, low clouds will linger through 15z across the northern TAF sites, finally rising above 3000 feet agl by 18z. Low level cyclonic circulation across south Alabama will likely keep the low cigs from rising significantly during the morning hours, but would still expect cigs to rise above 3000 feet agl by 21z. 58/rose && .FIRE WEATHER... Showers are likely across much of the area this evening, but rainfall amounts should be fairly light. Dry weather is expected to return for Friday and through the weekend. There are no fire weather concerns at this time. && .PRELIMINARY POINT TEMPS/POPS... Gadsden 51 62 44 65 44 / 20 0 0 0 0 Anniston 54 63 46 66 47 / 20 10 0 0 0 Birmingham 53 63 46 67 46 / 20 0 0 0 0 Tuscaloosa 53 66 45 68 46 / 20 0 0 0 0 Calera 54 63 46 66 46 / 20 10 0 0 0 Auburn 57 66 49 69 51 / 40 10 10 0 0 Montgomery 57 67 48 69 48 / 40 10 10 0 0 Troy 58 69 49 70 49 / 70 10 10 0 0 && .BMX WATCHES/WARNINGS/ADVISORIES/... Dense Fog Advisory until 8 AM CST Friday for the following counties: Autauga...Barbour...Bibb...Blount...Bullock... Calhoun...Chambers...Cherokee...Chilton...Clay...Cleburne... Coosa...Dallas...Elmore...Etowah...Greene...Hale...Jefferson... Lee...Lowndes...Macon...Marengo...Montgomery...Perry...Pike... Randolph...Russell...Shelby...St. Clair...Sumter...Talladega... Tallapoosa...Tuscaloosa. && $$