Area Forecast Discussion
Issued by NWS Memphis, TN
Issued by NWS Memphis, TN
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365 FXUS64 KMEG 291757 AFDMEG Area Forecast Discussion National Weather Service Memphis TN 1257 PM CDT Mon Apr 29 2024 ...New AVIATION... .UPDATE... Issued at 1100 AM CDT Mon Apr 29 2024 A mild and overcast morning across the Mid-South at this hour. Temperatures are steady around the 70 degree mark. The latest KNQA radar sweep reveals a poleward fetch of showers traveling nearly parallel to the Mississippi River. A few pockets of heavier returns were seen near Shelby County, TN in the past couple of scans. The latest GOES East Water Vapor Imagery loop shows an closed upper low over the Dakotas, deep southwesterly flow over the Mississippi Valley, a shortwave digging over southeast Texas, and a highly amplified ridge over the eastern CONUS. The overall trend is for showers to continue through this afternoon across much of the Mid-South with the potential for some lightning to develop by early afternoon, as the aforementioned Texas shortwave lifts into the Lower Mississippi Valley. The severe threat remains low, however, lightning and heavy rainfall are both possible. There is a potential for some stronger instability to develop along and east of the Mississippi River, which could enhance both a heavy rainfall threat and a limited wind threat this afternoon. No major changes were made to the forecast grids. Forecast is on track with temperatures nearly steady across much of the area. AC3 && .SYNOPSIS... Issued at 405 AM CDT Mon Apr 29 2024 A wet and unsettled pattern will continue today with rain chances increasing this afternoon. Daily bouts of rainfall will resume on Wednesday with chances for widespread shower and thunderstorm development Friday. Somewhat cooler and drier conditions are expected this upcoming weekend. && .DISCUSSION... (Today through Sunday) Issued at 405 AM CDT Mon Apr 29 2024 Remnant showers from the QLCS that pushed through southern Arkansas on Sunday are struggling to overcome the stable environment across the Mid-South. As a result, showers continue to diminish over northwest Mississippi. A few showers may continue through mid-morning, but overall coverage will be sparse. There exists potential for showers and storms to redevelop this afternoon as a large upper low pushes into the Great Lakes Region, ejecting a cold front into central Arkansas. Storm development may further be aided by a shortwave that is progged to develop within the trough axis by 18Z. Given overcast skies and highs in the low to mid 70s today, only marginal instability will be in place this afternoon. Therefore, any storm that does form should remain subsevere. A few strong storms may be possible if more instability is realized, but overall the threat is low. Behind today`s system, an upper level ridging pattern will emerge with high pressure centered over southeast CONUS. Both the GFS and ECMWF continue to depict embedded shortwaves rotating around the periphery of the ridge by Wednesday. As a result, daily rounds of precipitation will be possible through the end of the week. Widespread showers and thunderstorms will be possible on Friday as a negatively tilted trough pushes into the Great Lakes Region, bringing a cold front towards the Mid-South. Thunderstorms will likely develop along and ahead of this boundary, but the severe weather threat at this time appears low given lack luster wind shear. Unfortunately, it appears at this time that the aforementioned front will washout over the Mid-South on Saturday. Therefore, expect rain chances to persist into the weekend with afternoon highs in the upper 70s to low 80s. ANS && .AVIATION... (18Z TAFS) Issued at 1250 PM CDT Mon Apr 29 2024 A disorganized line of pre-frontal showers is currently traversing the region with very little lightning activity. However, as the actual front catches up later this afternoon/evening, much stronger forcing will lead to the development of more widespread clusters of showers with embedded thunderstorms. TEMPO groups were added to all sites with TSRA as these clusters move west to east through sunset with briefly reduced ceilings and/or visibilities. Guidance is still fairly split on the potential for low ceilings after the front overnight; the HRRR paints a broad swath of IFR to LIFR ceilings while the HREF as a whole and MOS guidance are more on the optimistic side with MVFR ceilings and more of a scattered lower deck. There is fairly low confidence in the presence of IFR ceilings anywhere but JBR overnight. Winds should start out southerly this afternoon and gradually shift to the north tomorrow morning behind the front, generally remaining in the 6-8 kt range. CAD && .MEG WATCHES/WARNINGS/ADVISORIES... AR...None. MO...None. MS...None. TN...None. && $$ PUBLIC FORECAST...ANS AVIATION...CAD