Area Forecast Discussion
Issued by NWS Memphis, TN
Issued by NWS Memphis, TN
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798 FXUS64 KMEG 232042 AFDMEG Area Forecast Discussion National Weather Service Memphis TN 342 PM CDT Thu May 23 2024 ...New SYNOPSIS, DISCUSSION... .SYNOPSIS... Issued at 245 PM CDT Thu May 23 2024 A series of upper-level disturbances will bring a potential for showers and thunderstorms each day to the Mid-South through Sunday. The greatest threat for severe thunderstorms will be mainly Friday and Saturday evenings, and Sunday afternoon into Sunday night. Large hail and damaging winds will be the primary severe weather threats along with a potential for heavy rainfall. A cold front will bring slightly cooler and drier air to the region by next Tuesday. && .DISCUSSION... (This evening through next Wednesday) Issued at 245 PM CDT Thu May 23 2024 GOES-16 satellite trends this afternoon show a decaying MCS gradually evolving into an MCV over the Lower Mississippi and Tennessee Valleys. Most of this morning`s showers and thunderstorms have since pushed away from the Mid-South. Temperatures as of 3 PM CDT are predominantly in the 70s to around 80 degrees due to earlier convection and cloud cover. Strong to severe thunderstorm potential through Sunday night remains the predominant concern in this afternoon`s forecast issuance. An active pattern will remain in place across the Lower Mississippi Valley as a series of shortwave troughs move through the lower Mississippi Valley into Saturday night. An isolated shower or thunderstorm or two may develop into early evening across the area but confidence remains low at this time. Otherwise, a minimum in convective activity is expected until a nocturnal low-level jet develops later this evening over the ArkLaTex and combines with a subtle mid-level shortwave trough to produce additional showers and thunderstorms across the area overnight into Friday morning. Short-term models including Convective Allowing solutions have struggled with the weak mid- level flow. Nonetheless, it appears daytime convection could be in the form of an MCS gradually evolving into an MCV. Strong surface-based instability combined with steep mid-level lapse rates, and 0-6 km Bulk Shear between 30-40 kts indicate a potential for some strong to severe thunderstorms Friday afternoon and again Friday night as a weak front meanders into the Mid- South. Additional strong to severe thunderstorms are possible Saturday evening as the front retreats back north as a warm front. High precipitable water values will pose a potential for heavy rainfall and possible flooding due to saturated soils and thunderstorms producing efficient rainfall rates. Mid to long range model runs continue to indicate a potential for organized convection across the Mid-South Sunday afternoon into Sunday night across the Lower Mississippi Valley as a negatively- tilted upper-level trough rotates from the Middle Mississippi Valley into the Ohio Valley. The best upper-level forcing may be displaced somewhat upstream. However, sufficient shear and instability will be present to produce strong to severe thunderstorms. Large hail and damaging winds continue to be the primary severe weather threats. 0-1 km storm relative helicities and clockwise curved hodographs suggest a potential tornadic threat may exist especially over portions of West Tennessee. This potential event will continue to be monitored in subsequent model runs. A cold front will bring a gradual end to showers and thunderstorms by early next week as cooler and drier air filters into the region. CJC && .AVIATION... (18Z TAFS) Issued at 1228 PM CDT Thu May 23 2024 Showers and thunderstorms continue to push across the Mid-South today, with activity waning over MEM and JBR. A few CAMs support redevelopment of TSRA near MEM later this afternoon, so kept PROB30 group in TAF. Chances for TSRA will increase again by 12Z Friday. Otherwise, VFR CIGs will prevail with MVFR possible within storms. ANS && .MEG WATCHES/WARNINGS/ADVISORIES... AR...None. MO...None. MS...None. TN...None. && $$ PUBLIC FORECAST...CJC AVIATION...ANS