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992 FXUS64 KMOB 042202AFDMOBArea Forecast DiscussionNational Weather Service Mobile AL402 PM CST Sat Jan 4 2025...New NEAR TERM, SHORT TERM, LONG TERM, MARINE....NEAR TERM...(Now through Monday) Issued at 402 PM CST Sat Jan 4 2025A rather potent system is expected to move through Sunday nightbringing gusty winds, life threatening beach conditions and the potential for some strong to severe storms with damaging winds andpossibly a tornado or two to parts of the area. Synopsis...A rather potent trough will move into the area Sundayinto Sunday night as shortwave ridging lifts off into theAtlantic. A strong surface low will move across the Ohio Valleywith a strong arctic front in tow. Southwesterly flow willoverspread the area as a tongue of moisture surges inland as aweak warm front surges north. This will allow for isolated toscattered showers storms to develop during the day on Sunday. Asthe surface cold front moves in from the west, a strong squallline will likely develop along the front and push across the areaSunday night. Expect areas to pickup around an inch or so of raintapering off east of I-65 during the overnight hours Sunday intoearly Monday morning. Behind the front, temperatures will plummetrapidly into the 30s and 40s. Highs on Monday may even struggle toget above 40 degrees depending on how quickly the system movesthrough and how quickly temperatures drop. Severe thunderstorms...The severe forecast for this system remains difficult as with most winter-time systems. Most of the area probably will not see severe thunderstorms except across our far western portions of our area where the best jet dynamics move in around midnight or just before midnight Sunday before lifting offto the northeast. Given the deep layer wind fields, shear will not be an issue with rather large curved hodographs supportive of organized storms likely in the form of a squall line (QLCS). The presence of a 50-60 knot 850mb low level jet will allow for high shear around 40 knots in the lowest kilometer along with SFC-1KM SRH values approaching 300 to 400 m2/s2. The question that remainsrevolves around instability or the lack there of. Overall trends have settled and even the high resolution guidance (which tends tohandle winter time instability better) is struggling with lining up the better instability. The lack of instability, especially with eastward extent will be the limiting factor in this event. Inthese high shear/ low CAPE (instability) setups we heavily rely on strong upper level support and lift and this will likely be confined right along the front likely keeping the QLCS potential alittle higher. Recent trends have been for the forcing to move a little quicker than originally expected which may yield a rapidly weakening line than originally anticipated. However, as the line enters our area from the west, there appears to be a small window as it progresses across southeastern Mississippi where upper levelforcing will be sufficient to support a severe threat. This area has been highlighted by a slight risk given the slightly higher confidence. Damaging winds will likely be the primary threat giventhe strong low level flow, but also be supportive of QLCS mesovortex development and thus a potential QLCS tornado threat across southeastern Mississippi in surface instability can be realized. As the line moves through Alabama and the far western Florida Panhandle late Sunday night, the strong low level flow maybe enough to support a localized damaging wind threat with any stronger storms but a more widespread severe risk seems rather lowconfidence and unlikely once we cross the state line into Alabama. Wind....As the upper trough moves in a rather tight pressure gradient will develop between the upper ridge to our east and the deepening low to our west. This will allow for rather strong low level flow to develop across the area beginning Sunday afternoon and lasting overnight. 925 mb winds will intensify to nearly 45 knots just a few thousand feet off the surface in the evening. This low level jet coupled with some level of surface instability despite being the overnight hours will allow for strong wind guststo mix down to the surface. As a result, wind gusts up to 35 mph will be possible late Sunday afternoon through Sunday night. Onceagain the limiting factor an maybe a stronger gradient wind eventwill be the limited instability and mixing. For now we will likelystay just below advisory criteria.Coastal Hazards...In addition to the severe potential, we arelooking at the potential for at least High Surf Advisory conditions along the coast of the western Florida Panhandle into coastal Alabama Sunday afternoon into Monday with strong southerlywinds bringing surf heights upwards of 5 to 7 feet. There is potential for surf heights to rise to near 8 feet, particularly ifthe winds end up being a bit stronger than expected. A Low risk of rip currents today becomes a Moderate risk by tonight and a High risk by Sunday into Sunday night. BB/03 /22&&.LONG TERM...(Monday night through Saturday) Issued at 402 PM CST Sat Jan 4 2025In the extended, temperatures mid week and possible winter weather the end of the week remain the biggest items to deal with.Looking at the synoptics, a mean upper trough over the eastern Conus moves off, with a weak upper ridge moving over the Mississippi River through mid week. Surface high pressure moves over the Mid-Mississippi River Valley, keeping the majority of the Southeast under cold northerly flow through mid week. Shortwave energy moving through the ridge passes over the Southeast the end of the week. Guidance is advertising a surface low developing over the western Gulf of Mexico Wednesday night with this energy. The surface low then moves northeast across the forecast area the end of the week. Through mid week, the influx of cold air with the continued northerly flow will keep temperatures well below seasonal norms. High temperatures in the mid to upper 50s north of I-10 are expected, with low to mid 50s south. Low temperatures in the 20s over the majority of the forecast area (around 30 along the coast) are expected Monday through Wednesday nights. Combined with the continued northerly winds, apparent temperatures dropping into the 13F to 20F range are expected, with Cold Weather Advisories expected. Thursday into Saturday, increasing isentropic upglide will bring rain to land portions of the forecast area as the surface low approaches, with a few thunderstorms interspersed over the Gulf. If the surface low takes a more southerly path, or is a bit quicker in moving in, there is a possibility of freezing rain or sleet as the precipitation moves in. This current package says no, with the airmass remaining warm enough ahead of the advancing precipitation as low level flow becomes more east to southeasterly, and radiational cooling cloud limiting cloud cover overspreads the forecast area. Will need to monitor, though, with model inconsistency a problem. Low temperatures Thursday night are expected to range from around 30 northeast of a Butler to Opp line, mid to upper 30s southwest, with sounding just warm enough to keep the falling precipitation liquid as it begins to overspread the forecast area later Thursday night. Again, will have continue monitoring the forecast for Thursday night into Friday. High temperatures in the mid 40s to around 50 Thursday rise into the upper 40s north of Highway 84 to mid 50s south of I-10. /16 &&.MARINE...Issued at 402 PM CST Sat Jan 4 2025Small Craft Advisory remains in effect for the Gulf Waters starting late tonight, followed by a Gale Watch starting Sunday evening and continuing through Monday morning. Gale conditionsremain likely over the far offshore waters and a Gale warning willlikely be needed for frequent gusts. Moderate southeasterly flowwill quickly increase this evening to Small Craft Exercise Caution criteria, followed by a strong onshore flow late tonight and Sunday ahead of a strong cold front approaching from the west.A moderate to strong offshore flow is expected on Monday in the wake of the front and advisory conditions may continue into themiddle of next week. BB/03&&.PRELIMINARY POINT TEMPS/POPS...Mobile 50 71 42 46 27 47 25 49 / 20 40 90 10 0 0 0 0 Pensacola 52 70 53 54 30 48 30 49 / 10 30 90 20 0 0 0 0 Destin 51 70 60 60 32 49 32 51 / 0 20 90 30 0 0 0 0 Evergreen 40 67 48 49 25 45 23 46 / 10 40 80 10 0 0 0 0 Waynesboro 44 68 32 42 24 44 23 45 / 20 60 100 0 0 0 0 0 Camden 40 66 40 42 25 43 22 43 / 10 40 100 10 0 0 0 0 Crestview 41 69 56 56 25 48 23 49 / 10 30 90 20 0 0 0 0 &&.MOB WATCHES/WARNINGS/ADVISORIES...AL...High Rip Current Risk from Sunday morning through late Monday night for ALZ265-266. High Surf Advisory from 9 AM Sunday to 6 PM CST Monday for ALZ265-266.FL...High Rip Current Risk from Sunday morning through late Monday night for FLZ202-204-206. High Surf Advisory from 9 AM Sunday to 6 PM CST Monday for FLZ202-204-206.MS...None.GM...Small Craft Advisory from noon Sunday to 9 AM CST Monday for GMZ630>636. Small Craft Advisory from midnight tonight to 6 PM CST Sunday for GMZ650-655-670-675. Gale Watch from Sunday evening through Monday morning for GMZ650- 655-670-675.&&$$This product is also available on the web at:www.weather.gov/mob
