362 FXUS64 KBMX 182356 AFDBMX Area Forecast Discussion National Weather Service Birmingham AL 656 PM CDT Fri Oct 18 2019 .UPDATE... For 00Z Aviation. && .SHORT TERM... /Updated at 0310 PM CDT Fri Oct 18 2019/ Through Saturday. --Tropical Storm Nestor to bring modest effects to Central Alabama-- At 20:10Z/3:10 PM, satellite showed mid- and high-level clouds moving northward through Central Alabama & regional RADAR showed Gulf Coast rain associated with a surface front. Newly classified Tropical Storm Nestor, located in the central Gulf of Mexico, was moving quickly northeastward at about 22 MPH per the 1 PM CDT advisory. Nestor's landfall is forecast early Saturday morning along the Florida Panhandle, with the system expected to quickly become post-tropical given further frontal interaction/evolution. Highlights_ Wind: 'Noticeably breezier' winds could occur for portions of East Alabama, with the highest gust potential upwards of 25-30 MPH seemingly focused southeast of Interstate 85 (lower elsewhere, especially for West Alabama) late tonight into Saturday. Rain: Flooding rainfall is not expected given our placement on the western perimeter of the precipitation shield + Nestor's fast forward motion. Overall, the highest chance of rain is forecast generally near and east of Interstate 65, though showers are possible farther west. The latest storm total rainfall forecast has between 0.5" to 1" for portions of far East Alabama, with totals below 0.5" elsewhere. 89^GSatterwhite .LONG TERM... /Updated at 0310 PM CDT Fri Oct 18 2019/ Update on Monday Severe Risk. A closed upper level low is forecast to move east across the High Plains and into the Upper Mississippi River Valley. The trough orientation will remain fairly neutral in tilt. Meanwhile, deep- layer ridging will become positioned further southeast of the local area being centered over the Bahamas. Toward the surface, a diffuse warm front is forecast to lift northeast across the area during the morning hours while a well- defined cold front advances eastward through Arkansas toward the Mississippi River. Expect increasing clouds through the day as rain chances increase from the northwest early morning and expand eastward through the day. At this time, most of the activity should remain west of Interstate 65 through the early evening hours. Look for lows to range from the upper 50's northeast to the mid 60's west and southwest Monday morning with highs ranging from the mid 70's east and northeast to around 80 south and southwest. Thunderstorm activity will likely accompany the shower activity as instability values appear to be sufficient, especially from late morning through the afternoon and into the early evening hours. The proximity of the upper level low to the north may encourage development of surface low pressure in the Southern Ohio River Valley region and if this materializes there may be better dynamical support for organized strong to severe thunderstorm activity, especially in the afternoon and into the early evening hours. At this time, the risk is conditional and marginal in nature due to forecast limited surface-based instability and wind shear profiles. The best potential for strong to severe storms would be across our northwest counties, generally near and northwest of the Interstate 59 corridor. The primary risks would be for damaging straight-line winds and potential for an isolated tornado. There remains considerable uncertainty in synoptic and mesoscale details that leads us to maintain a 1 out of 5 risk for severe storms and possible tornadoes in the Hazardous Weather Outlook product. 05 Previous long term discussion: /Updated at 0417 AM CDT Fri Oct 18 2019/ Sunday through Friday. Between weather systems, height rises will take place on Sunday as a significant trough digs toward the Southern Plains. A dry and warm afternoon is expected under the influence of southerly flow. Temperatures should reach the upper 70s in the north with lower 80s across the south. Rapid surface pressure falls will take place Sunday night into Monday across the span of the Mississippi River Valley as a powerful jet carves out a deep trough centered over the Upper Midwest. A strong low-level jet is expected to be located along the MS River at 12Z Monday with upper 60s to lower 70s dewpoints advecting northward across the ArkLaMiss and Alabama. Much of our forecast area should remain dry through noon, but a band of showers and storms should move in from the west during the afternoon and evening. Models generally agree that pressure falls will be minimal across Alabama as the system becomes occluded. However, our northwestern counties may be clipped by a 35-45 kt low-level jet around 18-21Z Monday. With SBCAPE of 500-1000 J/kg, there may be a non-zero threat for isolated damaging winds and perhaps a brief tornado. Farther east, there is good agreement regarding weakening low-level jet as the low over the Upper Midwest becomes more vertically stacked. Though low-level shear does not appear to support a tornado threat, 700-500 mb flow of 40-50 kt may be sufficient for an isolated damaging wind threat to continue eastward across the forecast area. For now, a marginal risk of severe storms will be introduce for areas north of I-20/59 and west of I-65. Cooler and much drier air will move into the region on Tuesday behind a cold front. High pressure should remain in control through Thursday. The next chance of rain may start come on Friday as another trough develops to our northwest. 87/Grantham && .AVIATION... 00Z TAF Discussion. Deteriorating weather conditions will spread from south to north across central Alabama through the next 24 hours, as Tropical Storm Nestor moves northeastward from the Gulf toward the Gulf Coast. Given the current forecast track, the worst conditions will be experienced at TOI, with slightly "better" conditions expected as you head north and west from there. TCL may very well remain VFR the whole time, but other central Alabama TAF locations will probably experience at least a several hour period of MVFR. Locations not named ANB, ASN, and TOI, may even see some improvement beyond the 18z-21z time frame. But the bulk of the improvement (at least in ceiling heights) probably won't come until after 00z tomorrow. /61/ && .FIRE WEATHER... Tropical Storm Nestor will spread rain and breezy conditions into central Alabama, especially the southern portion, through Saturday. The area should see a return to dry weather by Sunday. But a cold front will likely bring a round of showers and thunderstorms on Monday. The Alabama Forestry Commission continues to have a fire alert in effect that includes all of Central Alabama. For more information about restrictions, visit their web site at forestry.alabama.gov. && .BMX WATCHES/WARNINGS/ADVISORIES/... None. && $$