Forecast Discussions mentioning any of "HRRR" "RAP" "RUC13" "RUC" "RR" received at GSD on 11/26/22

Area Forecast Discussion
National Weather Service Mobile AL
530 PM CST Fri Nov 25 2022 ...New AVIATION... .AVIATION... (00Z TAFS) Issued at 524 PM CST Fri Nov 25 2022 Predominately IFR ceilings over the area lower to LIFR/IFR along with patchy fog overnight, then improve to IFR-MVFR ceilings Saturday morning. Will need to monitor overnight for the potential of VLIFR conditions in fog, but at this time this does not look to be likely. A line of convection is expected to advance into the western portions of the area Saturday afternoon. Generally light northerly to northeasterly winds overnight become easterly 5 to 10 knots Saturday morning then become southeasterly in the afternoon. /29 && .PREV DISCUSSION... /issued 348 PM CST Fri Nov 25 2022/ ..New NEAR TERM, SHORT TERM, LONG TERM, MARINE... NEAR AND SHORT TERM... (Now through Sunday night) Issued at 214 PM CST Fri Nov 25 2022 A westerly to southwesterly flow pattern aloft generally prevails across the north central Gulf Coast region this afternoon well in advance of a deep area of low pressure that remains located in the vicinity of far west TX and adjacent northern portions of Mexico. A cold front has been sinking southward across our forecast area through the day and is generally oriented along and south of a Wiggins MS, Mobile AL, Florala AL line as of 3 PM CST. Temperatures along and north of the boundary generally range in the upper 50s to mid 60s, while temperatures closer to the coast have warmed into the upper 60s to mid 70s (and even near 80 earlier around Destin). A solid deck of low stratus clouds has kept skies overcast for the most part around the region this afternoon. Very weak isentropic ascent has also resulted in the development of light drizzle and light rain showers near the coast. There is little change to overall forecast expectations for tonight. Shortwave ridging aloft is expected to develop across our region this evening before shifting to our east late to night as southwesterly flow aloft begins to re-develop across region ahead of the deep low pressure system that will slowly be lifting across southwest/west TX. We generally expect dry weather conditions over the area this evening into late tonight, though a return of weak isentropic ascent may result in the development of isolated light rain showers across portions of southeast MS by late tonight. Patchy fog development will once again be possible, especially along and north of the I-10 corridor later tonight. Overnight lows are forecast to range in the lower to mid 50s across interior portions of southeast MS and southwest/south central AL and in the upper 50s to lower 60s near the coast. A return to wet and stormy weather with an associated potential for heavy rainfall and a few severe storms is still expected from late Saturday afternoon through late Saturday night. The low pressure system over TX will take on a negative tilt as it crosses the Red River Valley late Saturday afternoon and lifts toward the Mid-Mississippi Valley region Saturday night into early Sunday morning. An associated 100-120 kt mid/upper level jet streak will lift from east TX toward the Mississippi Valley late Saturday afternoon into Saturday night and a region of forced ascent and associated organized bands of convection or QLCS will advance eastward into our forecast area during this time. Strong low level and deep layer shear will be present across our forecast area with southerly to southwesterly 850 mb flow still looking to strengthen to 50+ knots Saturday evening/night, while 0-6 km shear also increases to 55-65 knots. Low level curvature to the wind flow will also support 0-1 km SRH values up to between 250-400 m2/s2 Saturday evening/night. While the shear is very robust for organized convection, instability still remains the uncertain and limiting factor for severe weather potential and coverage across our forecast area. Some of the latest available CAMs, such as the 18Z HRRR and 12Z WRF-ARW bring convection into western portions of our forecast area as early as 5-6 PM Saturday, which in turn would limit the northward extent of low level warm/moist advection and associated higher instability values into our area. This may keep the severe weather/tornadic threat relegated closer to the coast or offshore over the Gulf. On the other hand, a slower solution such as the NAM would allow for better return flow/moisture return further north into our area ahead of the approaching convective line, and an associated better potential for organized severe convection across our CWA. The severe risk remains marginal at this time, and is largely dependent on if convection will be able to tap into surface based instability. Localized damaging winds and perhaps a tornado or two remain the main concern, so residents over the region should remain weather aware late Saturday afternoon into late Saturday night and have ways to receive warning information. Heavy rainfall will also be possible with much of our forecast area expected to receive between 1-2" of rain with localized amounts over 3" possible. Heavy rains falling in a short period of time will be capable of producing localized flooding of urban and low lying areas. Breezy conditions may develop with the strengthening low level jet and surface gradient Saturday evening/night. Gusts could range between 25-35 mph across the region. Showers and thunderstorms should end from west to east late Saturday night into early Sunday morning, with current expectations that the severe threat should largely end over our eastern zones by around 4 AM. We expect dry weather Sunday into Sunday night. /21 LONG TERM... (Monday through Friday) Issued at 214 PM CST Fri Nov 25 2022 A dry westerly to southwesterly flow aloft is expected to prevail across our region Monday and Monday night. The next weather system of interest will be a deepening trough over the central CONUS Tuesday. A shortwave trough embedded in southwesterly flow aloft ahead of this feature may propagate across the Lower MS Valley and adjacent TN Valley/Gulf Coast states sometime in the Tuesday afternoon through Wednesday time frame. Increased southerly flow/ low level moisture return into our area ahead of this system and its associated cold front (along with a region of increased ascent) will bring our next good chance of showers and thunderstorms late Tuesday into Wednesday. Strong shear combined with perhaps better moisture return and available instability may result in organized severe weather concerns across portions of our area going into Tuesday night and Wednesday. This will be something to watch over the next few days. Cooler temperatures and dry weather are currently expected for the latter part of the week. /21 MARINE... Issued at 214 PM CST Fri Nov 25 2022 Moderate northerly flow will continue through this evening, but is expected to become easterly late tonight. Seas will build and moderate onshore flow will become strong by Saturday evening with the approach of a cold front. Winds will then shift to be westerly early Sunday morning as the front passes over the marine waters. Small Craft Advisories are therefore in effect for all bays and sounds, as well as the Gulf waters, beginning 21Z Saturday afternoon. Winds and seas will then gradually decrease into early next week, but moderate onshore flow is expected to develop once again for Tuesday and into midweek. /26 && .PRELIMINARY POINT TEMPS/POPS... Mobile 58 72 56 72 50 70 53 75 / 10 70 100 0 0 0 0 30 Pensacola 60 74 61 72 54 72 56 74 / 10 50 100 10 0 0 0 20 Destin 62 76 65 74 57 73 59 75 / 10 40 90 20 0 0 0 20 Evergreen 54 70 55 69 45 70 46 74 / 0 40 100 10 0 0 0 20 Waynesboro 54 69 51 67 45 66 46 72 / 10 80 100 0 0 0 0 40 Camden 52 68 54 67 45 65 46 71 / 0 40 100 10 0 0 0 30 Crestview 58 71 60 71 48 70 49 74 / 0 30 100 10 0 0 0 20 && .MOB WATCHES/WARNINGS/ADVISORIES... AL...High Rip Current Risk from Saturday evening through late Sunday night for ALZ265-266. FL...High Rip Current Risk from Saturday evening through late Sunday night for FLZ202-204-206. MS...None. GM...Small Craft Advisory from 3 PM Saturday to 9 AM CST Sunday for GMZ630>636. Small Craft Advisory from 3 PM Saturday to 3 PM CST Sunday for GMZ650-655-670-675. && $$ This product is also available on the web at: