058 FXUS64 KMEG 301140 AFDMEG Area Forecast Discussion National Weather Service Memphis TN 640 AM CDT Sat Mar 30 2019 .DISCUSSION... /issued 447 AM CDT Sat Mar 30 2019/ Mild and humid conditions in store for today, ahead of a northern branch upper trof and associated surface cold frontal passages. Instability will gradually build during the day, capped by an elevated mixed layer (EML). The EML will eventually erode with midlevel height falls. This appears most likely to occur east of the MS River this afternoon. A low level instability axis will prevail over north MS into southwest TN east of the Memphis metro. NAM-progged MUCAPES reach 2000 J/KG in spots, perhaps yielding stronger updrafts than earlier guidance suggested. Directional shear remains modest, which should keep storms primarily linear. Given the amount of instability, some bowing and enhanced damaging wind threat will be possible near any mesoscale frontal waves. 850-500mb lapse rates near 6.25 C/km will be supportive of large hail in the strongest storms. Otherwise, damaging winds remains the primary concern. 3km NAM Nest model timing appears on target, with a few morning storms over northeast AR, and a narrow line of convective redevelopment downstream over west TN and north MS during the afternoon/early evening. Following storms exit this evening, skies will clear overnight as a continental polar airmass settles in. By sunrise Sunday, wind chills will likely prevail in the 20s north of I-40, in marked contrast to the mild and humid conditions on Saturday. Today's 00Z medium range model guidance brings the center of the continental polar high pressure a little closer to the Midsouth Monday morning, from KY westward to the Ozark Plateau. Despite some high clouds, subfreezing temps will be possible toward sunrise Monday over a good portion of the Midsouth. GFS/ECMWF/Canadian models depict an open midlevel wave passing through the Midsouth Monday night. Today's 00Z ECMWF has come into consensus with earlier GFS and Canadian runs in keeping this system dry for the Midsouth. Northwest flow aloft will quickly transition to southwesterly by Wednesday, in advance of an upper trof lifting through the plains. Showers and thunderstorms associated with this system should affect the Midsouth on Thursday, with lingering showers persisting perhaps as late as Friday morning. The upcoming weekend appears dry and mild for Saturday, under shortwave ridging aloft. The following sunday appear to be more unsettled, as a southern branch upper low lifts through the lower MS River valley. PWB && .AVIATION... 12Z TAF Set MVFR CIGS will spread up the MS Delta this morning and then begin to erode from east to west. Spotty showers will be possible this morning, but will be very hit and miss. Cold front will push into the CWA around 18Z. Expect a narrow line of showers and thunderstorms to accompany the front through. CIGS may temporarily lower to IFR with the line. Lingering light rain with MVFR CIGS will continue for a couple of hours after frontal passage. Thereafter, clearing will take place during the evening hours. Gusty southwest winds of 12-16 KTS sustained with higher gusts will occur ahead of the front. Winds will then switch to the Northwest behind the front. Speeds may actually increase slightly with sustained speeds of 16-18 KTS with gusts up to near 30 KTS. Speeds will gradually decrease during the overnight hours as winds switch to the NNE. KRM && && .MEG WATCHES/WARNINGS/ADVISORIES... AR...Freeze Watch from late Sunday night through Monday morning for Clay-Craighead-Crittenden-Cross-Greene-Lee AR-Mississippi- Poinsett-St. Francis. Freeze Watch from late tonight through Sunday morning for Clay- Craighead-Greene-Poinsett. MO...Freeze Watch from late Sunday night through Monday morning for Dunklin-Pemiscot. Freeze Watch from late tonight through Sunday morning for Dunklin-Pemiscot. MS...Freeze Watch from late Sunday night through Monday morning for Alcorn-Benton MS-Chickasaw-DeSoto-Itawamba-Lafayette-Lee MS- Marshall-Monroe-Panola-Pontotoc-Prentiss-Tate-Tippah- Tishomingo-Tunica-Union. TN...Freeze Watch from late Sunday night through Monday morning for Benton TN-Carroll-Chester-Crockett-Decatur-Dyer-Fayette- Gibson-Hardeman-Hardin-Haywood-Henderson-Henry-Lake- Lauderdale-Madison-McNairy-Obion-Shelby-Tipton-Weakley. Freeze Watch from late tonight through Sunday morning for Henry- Lake-Obion-Weakley. && $$