Area Forecast Discussion
Issued by NWS Mobile, AL
Issued by NWS Mobile, AL
Versions:
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
571 FXUS64 KMOB 122143 AFDMOB Area Forecast Discussion National Weather Service Mobile AL 443 PM CDT Sun May 12 2024 ...New NEAR TERM, SHORT TERM, LONG TERM, MARINE... .NEAR TERM... (Now through Tuesday) Issued at 443 PM CDT Sun May 12 2024 An active weather pattern is set to return as we go into the early part of the upcoming week with multiple rounds of showers and thunderstorms bringing potential for very heavy rainfall and increased flooding concerns along with a threat of severe weather to our region. Weak shortwave ridging aloft across our forecast area this afternoon is expected to shift to our east this evening as a shortwave trough lifts from eastern portions of Texas into Louisiana and the Lower Mississippi Valley region. We are already seeing a rather large area of showers of thunderstorms spreading across these areas on radar/satellite this afternoon. Rain showers may arrive into our southeast MS and southwest AL zones late this afternoon into this evening, but rainfall amounts with this initial precipitation should be relatively light through this evening. Convection should ramp up in coverage and intensity across southeast MS and adjacent portions of southwest AL, especially after 4 AM Monday as a complex of showers and thunderstorms arrives into these areas ahead of the lead shortwave trough. A warm front stretching along coastal portions of MS to near the AL coast around 4 AM Monday morning should gradually advance inland through the morning hours, but the big question is how far north will this boundary get? There is still a lot of variability in the guidance with regard to the northward extent of this feature. Confidence is highest that the warm front may advance into southern portions of our southeast MS counties and across Mobile/Baldwin AL counties, and then to Pensacola and the adjacent immediate northwest Florida coast. Storms arriving over our interior counties overnight could remain elevated in nature with potential for only heavy rain and possibly some hail. If the boundary lifts further north through our CWA during the early morning hours, there could be a wind/tornado threat extending into our interior areas. If the boundary remains confined closer to the coast, then the better potential for damaging winds/tornadoes will be relegated along coastal portions of our CWA. Given the spread in guidance, the Slight (level 2 of 5) risk of severe weather was brought north through our entire CWA going into Monday. Some of the latest CAMs are in agreement with taking this first round of convection south of the coast by around noon or so Monday with lull in activity going into Monday afternoon. This lull looks to be short-lived as the next shortwave trough brings another convective complex into our forecast area by late Monday afternoon or Monday evening and continuing through Monday night/ Tuesday morning. Confidence in the severe threat late Monday night into Tuesday is lower and will be highly dependent on if instability can reload over our region following the first round of convection Monday morning. If instability reloads, there could be severe concerns (wind/tornado/possibly hail) across portions of our CWA during this time. The threat of flash flooding will also be on the increase with the multiple rounds of showers and thunderstorms expected to impact our region Monday morning through Tuesday morning/early Tuesday afternoon. The latest QPF/rainfall forecast is suggesting potential for 3 to 6 inches of rain with some pockets in excess of 8 inches possible over much of our area. A limiting factor could be the dry antecedent conditions, but given the signal for these heavy rainfall amounts (some of which could fall in a relatively short period of time), we have issued a Flood Watch for all of our forecast area from early Monday morning through early Tuesday afternoon. The rip current risk will increase to MODERATE on Monday and then to HIGH by Tuesday. The HIGH rip current risk will likely persist through much of the week. /21 && .SHORT TERM... (Tuesday night through Wednesday night) Issued at 443 PM CDT Sun May 12 2024 The upper level shortwave trough north of the forecast area moves off, with an upper level ridge moving over the Southeast. A drier, but not appreciably cooler airmass moves over the region, allowing high temperatures Wednesday to see an uptick from Tuesday (mid to upper 80s expected). Low temperatures see a downward trend, with clear skies, light winds, and the dry airmass allowing for good radiational cooling. Low temperatures mainly in the 60s Tuesday night drop into the around 60 to mid 60s range (near 70 along the coast) over most of the forecast area for Wednesday night. /16 && .LONG TERM... (Thursday through Sunday) Issued at 443 PM CDT Sun May 12 2024 Several rounds of shortwave energy move east through zonal upper flow over the Southeast the end of the week into the weekend. Guidance is consistent with energy passing in the Thursday into Friday night time frame, but there after diverge. For the first half of the Extended, showers and thunderstorms return by Thursday night, with moisture return Thursday the limiting the return factor for PoPs, especially the northeastern half of the forecast area. Will need to monitor this first round, with guidance advertising a warm front moving onshore over the Southeast Thursday night through Friday (but inconsistent in how far inland). For the weekend, have went with a blended approach for PoPs and temperatures, with the GFS and GDPS advertising a bit cooler and moister forecast, the ECMWF a warmer and drier scenario. Temperatures in the mid to upper 80s see a small dip Friday, with the highest PoPs this day, but rebound for the weekend. Low temperatures in the mid to upper 60s over most of the area (low 70s along the coast) are expected through the period. /16 && .MARINE... Issued at 443 PM CDT Sun May 12 2024 An approaching system will shift light to at times moderate easterly flow to moderate to at times strong southerly flow for the beginning of the week. A Small Craft Advisory may be needed, but conditions are borderline at this time. Light westerly flow returns for mid week, but another approaching system will bring moderate to at times strong onshore flow for the end of the week. /16 && .PRELIMINARY POINT TEMPS/POPS... Mobile 68 82 68 85 65 88 65 86 / 60 90 90 70 10 0 0 30 Pensacola 71 81 72 83 70 86 68 84 / 40 80 90 80 20 10 0 20 Destin 72 82 73 83 73 84 70 84 / 30 70 80 90 30 10 10 20 Evergreen 63 79 67 84 64 86 60 87 / 50 90 90 80 20 0 0 20 Waynesboro 62 79 65 85 62 85 60 85 / 80 90 80 50 10 0 0 30 Camden 61 77 65 84 63 84 59 85 / 60 90 90 80 20 0 0 10 Crestview 63 82 67 84 65 88 61 88 / 30 80 90 90 20 10 0 20 && .MOB WATCHES/WARNINGS/ADVISORIES... AL...Flood Watch from Monday morning through Tuesday afternoon for ALZ051>060-261>266. FL...Flood Watch from Monday morning through Tuesday afternoon for FLZ201>206. MS...Flood Watch from Monday morning through Tuesday afternoon for MSZ067-075-076-078-079. GM...None. && $$ This product is also available on the web at: www.weather.gov/mob