446 FXUS64 KBMX 131836 AFDBMX Area Forecast Discussion National Weather Service Birmingham AL 136 PM CDT Mon May 13 2019 .UPDATE... Afternoon Update. && .SYNOPSIS... A closed low was analyzed over eastern Great Lakes with a positive-tilted trough extending southwest from Ohio into central Arkansas while broad and ridging was placed over the Intermountain West. Another closed low was positioned in northern Mexico south of New Mexico. A surface cold front extended from the northern Gulf of Mexico northeast to near Tallahassee, FL and was aligned further northeast into the central Carolinas. Surface high pressure was located over much of Missouri and was continuing to build further into our region from the northwest early this afternoon. 05 && .SHORT TERM... The closed upper low over the eastern Great Lakes will move into upstate New York overnight while weak shortwave ridging builds to our southwest over the Texas and Louisiana coastal plain through the short-term period. The closed upper low over far northern Mexico opens into a positive-tilted trough and pulls eastward into central Texas by Tuesday morning. The cold front to our southeast will continue to slide further away, becoming positioned from the central Gulf of Mexico through the northern Florida peninsula after midnight tonight. Surface high pressure over much of Missouri will slide further east, becoming positioned over southeast Illinois overnight. Expect fair to partly cloudy skies to persist across our western and north-central counties for the remainder of this afternoon as a brisk northwest flow aloft prevails with the passage of the upper level trough axis. Skies will become mostly clear to clear overnight with decreasing winds overnight as surface high pressure makes its closest approach to our area, resulting in a further decreased surface pressure gradient. With fair skies and light winds expect lows tonight to range from the upper 40's across our northern tier and northeast higher elevations to the mid 50's across our southern and southwest lower elevation areas. A dry airmass will help to discourage fog formation despite calming winds overnight. Look for pleasant weather to continue into Tuesday with fair skies and high temperatures ranging from the low 70's north and northeast to the upper 70s's across our south and southwest counties. Winds will remain out of the north with speeds in excess of 10-15 mph at times tomorrow afternoon due to deep vertical mixing with daytime heating. 05 .LONG TERM... /Issued at 300 AM CT/ Modified forecast discussion for Wednesday through Monday. A weak upper level shortwave dips southward through the trough and pushes into the TN Valley Wednesday night through Thursday. This could lead to some scattered showers and thunderstorms for the northern half of Central AL, but the overall coverage will be limited due to the low level ridging and drier air in place. The moist southerly flow returns Friday as the surface high shifts to our east. The upper level ridge slides overhead Friday and Saturday, allowing for mostly clear skies. Our next weather system approaches lat Saturday into Sunday as a trough dips through the Central Plains. A frontal boundary will slowly push into the region Sunday into Monday, but exact timing remains uncertain. We also could see some height rises as the trough begins to flatten by the time the frontal boundary reaches our area; therefore, I've kept lower-end chance PoPs (roughly 30%) for Sunday into Monday. 25/Owen && .AVIATION... 18Z TAF Discussion. VFR conditions this afternoon and much of the evening areawide, with only a scattered cu field this afternoon. Winds from the northwest will be breezy at times, with sustained winds at 7-10kts. Cannot rule out a gust of 15-16kts. Winds will diminish this evening, with skies becoming clear. River/valley fog could develop late tonight with the cool temperatures, and have included IFR at ANB, ASN, and TCL. 14 && .FIRE WEATHER... Dry conditions will prevail across the forecast area through much of the day on Wednesday with northerly winds breezy at times this afternoon and again Tuesday afternoon due to deep vertical mixing. RH values will be lowest generally near noon time through 5 pm with readings in the 40 to 50 percent range due to the vertical mixing. There are no fire weather concerns at this time. && .PRELIMINARY POINT TEMPS/POPS... Gadsden 48 73 49 78 59 / 0 0 0 20 20 Anniston 49 73 50 79 60 / 0 0 0 10 10 Birmingham 52 75 54 80 62 / 0 0 0 10 20 Tuscaloosa 53 76 55 81 62 / 0 0 0 10 10 Calera 52 74 53 80 61 / 0 0 0 10 10 Auburn 53 74 53 78 60 / 0 0 0 10 10 Montgomery 54 78 54 82 61 / 0 0 0 10 10 Troy 54 77 53 80 60 / 0 0 0 10 10 && .BMX WATCHES/WARNINGS/ADVISORIES/... None. && $$