####018003787#### FXUS63 KABR 041509 AAB AFDABR Area Forecast Discussion...UPDATED National Weather Service Aberdeen SD 1009 AM CDT Sat May 4 2024 .KEY MESSAGES... - Dry conditions expected today and Sunday. Southeast to south winds begin to increase Sunday afternoon ahead of a Rocky Mountains low. - A much larger system looks to affect the region on Monday, with widespread moderate rainfall. The threat for severe weather still appears low at this time (higher across NE/KS/OK), but we will continue to monitor trends. && .UPDATE... Issued at 1008 AM CDT Sat May 4 2024 Current forecast is on track, therefore no changes made at this time. && .SHORT TERM /TODAY THROUGH SUNDAY AFTERNOON/... Issued at 412 AM CDT Sat May 4 2024 High pressure builds into the region this morning bringing dry conditions. However, an upper trough is slow to depart so max Ts are expected to remain below normal by 5 to 10 degrees. Weak upper ridging builds in tonight. High pressure exits to the east on Sunday leaving a tightening pressure gradient between the high and a Rocky Mountains low. Winds increase out of the southeast to south Sunday afternoon with gusts across central SD up to 50 mph. Will likely need to hoist a wind advisory for some locations in the forecast area as we get closer to the onset. The upper ridge and good mixing will push temperatures up around 70 degrees on Sunday, as well. && .LONG TERM /SUNDAY EVENING THROUGH FRIDAY/... Issued at 419 AM CDT Sat May 4 2024 Sunday night we continue to see an upper level ridge over the area. This will continue into Monday morning. However, Monday afternoon an upper level low starts to move into the region. This will stay in place through the day Saturday. This will bring widespread chances of rain to the region through the day Thursday. Monday looks to have the highest rain totals for the long term, along with a chance for some storms. Consistent with what we saw yesterday, NAEFS is still showing PWAT values in the 97.5 percentile, starting west river and then spreading east across the rest of northeast SD through the day. For QPF, the NBM is still showing 50 to 65 percent probabilities for more than a half an inch in 24 hours ending Tuesday morning. Probabilities of more than an inch in 24 hours are still 30 percent or less. Although rain totals may exceed expectations under storms. While models aren't showing a whole lot of CAPE (100-400 J/kg across the James valley, less elsewhere), Bulk shear values are between 35 and 50 kts across the region. This will sway the threat away from the hail side of things and more towards a wind threat, especially since we are already expecting stronger wind gusts. The Canadian model tries to bring back a chance for some storms on Wednesday, but other models disagree at the moment. PoPs start to decrease across the area Thursday evening. Speaking of winds, Sunday night into Tuesday morning is expected to be quite windy with gusts of over 40 mph possible. Sunday night, winds are fueled by a LLJ and Monday night, winds look to be enhanced by strong CAA coming in from the west. Winds should start to die down Tuesday during the day. Temperatures in the long term still look to be right around average to 10 degrees below average. && .AVIATION /12Z TAFS THROUGH 12Z SUNDAY/... Issued at 608 AM CDT Sat May 4 2024 Terminals KABR,KATY,KPIR,KMBG VFR conditions are expected through tonight. && .ABR WATCHES/WARNINGS/ADVISORIES... SD...None. MN...None. && $$ UPDATE...Parkin SHORT TERM...Wise LONG TERM...KK AVIATION...Wise ####018005297#### FXUS64 KJAN 041509 AFDJAN Area Forecast Discussion National Weather Service Jackson MS 1009 AM CDT Sat May 4 2024 ...New MESOSCALE UPDATE... .MESOSCALE UPDATE... Issued at 1001 AM CDT Sat May 4 2024 Some stratus continues to persist this morning but is beginning to dissipate across the area. Skies will become partly cloudy across most of the area this afternoon, but with weak disturbances combining with afternoon heating, expect isolated to scattered storms to develop this afternoon. Expect the storms to remain mostly below severe limits, but a strong storm or two will be possible. Highs this afternoon will climb into the mid 80s for most of the area./15/ && .DISCUSSION... Issued at 400 AM CDT Sat May 4 2024 Today and Tonight: Early morning satellite imagery/RAP analysis showed our CWA in the wake of a departing shortwave trough. The result was drying aloft with nearly zonal flow across our CWA. This has led to less cloud cover and the development of fog across our CWA. Patchy dense fog was currently being observed but the areas of dense fog is expected toward morning warranting the continuation of a Dense Fog Advisory for the whole CWA. The 00Z JAN sounding had a PWAT near and inch and a half. Early morning surface analysis still had a weak ridge nosing across our CWA from the east. Flow around this ridge will help maintain low level moisture while models show deep moisture increasing back across our CWA today from the west. Subtle disturbances within the near zonal flow aloft is expected to combine with daytime heating and our moist airmass for isolated to scattered showers and thunderstorms mainly during the afternoon. Although a strong storm or two cannot be ruled out, the main focus for severe storms will be to our west again today. This evening the convection will show a distinct diurnal trend and dissipate with the loss of daytime heating. Models do suggest some convective develop in our toward sunrise as a northern stream shortwave trough tries to drop a weak cold front close to our CWA. With a later start to the convection today, temperatures are expected to top out a few degrees above normal. Morning lows Sunday will continue above normal as well. /22/ Sunday: Continued rain and storm chances will be possible Sunday in the (30-50%) range as another short wave will pass through the area. Expect convection to be isolated to scattered as remnant storm activity in the high plains will be the main factor, as redevelopment will be possible in our area as heating occurs and instability increases by mid-day. Thus a marginal risk for severe storms has been added to the HWO with the main threats being isolated threat for damaging winds and hail. Monday through Wednesday: Expect above-normal temperatures early in the week, with heat persisting through mid-week. The mesoscale weather pattern shifts to the typical western trough to eastern ridge. As the ridge shifts eastward, southwesterly slow and surface ridging will help a strong surface high build into the ArkLaMiss region. THis will help low-level moisture to flow and keep surface temperatures well above normal. Minor rain and storm chances will hang around through mid-week in the (20-30%) range with there being a better storm environment in the far north that could produce better chances. Thursday and Friday: Come Thursday the forecast shifts as the potential for severe storms with Friday having higher confidence. Upper level troughing in the western plains will become negatively tilted and provide a source of multiple disturbances through late week. As a front pushes down into the region it is possible for some strong to severe storms to form along the front. For Friday the storm environment seems more conducive for severe storm production as lapse rates will steepen, increased moisture, shear and lift will all be present. Organized thunderstorms with the main threats being damaging wind and hail are anticipated. This event is possible however confidence isn't very high at this time as there is a good degree of uncertainty this far out in the forecast especially on timing. Following the cold front, much cooler temps will ensue going into next weekend. /KP/ && .AVIATION... (12Z TAFS) Issued at 626 AM CDT Sat May 4 2024 IFR/LIFR conditions wl prevail through 13Z. After 13Z conditions wl slowly improve through 16Z. After 16Z VFR conditions are expected to prevail areawide through 08Z Sunday. After 08Z Sunday IFR/LIFR conditions wl be psbl in the se with MVFR vsbys psbl elsewhere. /22/ && .PRELIMINARY POINT TEMPS/POPS... Jackson 86 65 84 67 / 40 30 50 40 Meridian 88 64 88 66 / 30 20 40 30 Vicksburg 86 66 82 66 / 40 30 50 40 Hattiesburg 89 66 88 67 / 30 20 30 10 Natchez 86 65 81 66 / 40 20 50 20 Greenville 85 67 81 67 / 30 30 60 50 Greenwood 85 67 84 67 / 30 30 70 60 && .JAN WATCHES/WARNINGS/ADVISORIES... MS...None. LA...None. AR...None. && $$ 15/