Area Forecast Discussion
Issued by NWS Memphis, TN
Issued by NWS Memphis, TN
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382 FXUS64 KMEG 221151 AAA AFDMEG Area Forecast Discussion...UPDATED National Weather Service Memphis TN 651 AM CDT Wed May 22 2024 ...New AVIATION... .SYNOPSIS... Issued at 305 AM CDT Wed May 22 2024 Active weather will persist for most of the forecast period. Strong to severe storms are possible for the next several days. A Slight Risk is in place for severe storms capable of producing damaging winds and large hail this afternoon. Several systems will cross the region for the remainder of this week that will also threaten damaging winds and large hail. && .DISCUSSION... (Today through Tuesday) Issued at 305 AM CDT Wed May 22 2024 A few lingering showers and storms are depicted on KNQA radar as of 3 AM with continuous signs of weakening. The remnants of any of this convection will help a MCS/MCV develop ahead of an approaching cold front. Southwesterly flow will surge a moisture plume and bring dewpoints into the 70s this morning. Deterministic soundings are indicative of a damaging wind and large hail as the primary threats this afternoon into evening. Inverted V soundings will provide excellent mixing with around 50kts of effective shear. Unstable lapse rates (~8 C/km) through the column with MLCAPE ~2500 J/kg and SHIP values >1 may bring large, to very large hail. On a positive note, SRH values are low (<100 m^2/s^2) which keeps the tornadic threat below the damaging wind and hail threat. PWs are in the 90th percentile or higher, meaning locally heavy rainfall is possible, particularly with any strong updrafts could lead to localized flooding. Current QPF values are highest for todays set of storms in the Mississippi Delta region. This round of convective activity will be aided by diurnal heating and look to fire up this afternoon ~1pm. Depending on where remnant outflow boundaries lie from overnight convection, this could change our severe weather outlook for today, hence the removal of the Enhanced to a Slight Risk. The aforementioned cold front is expected to stall tomorrow evening before lifting north as a warm front by Thursday evening. As a result of this, showers and thunderstorm chances remain in the forecast. Another Slight Risk for severe weather is in place for Thursday with a Marginal Risk for Friday. The placement of the LLJ will keep an active weather pattern across the Mid-South likely until Tuesday as series of systems will cross the region. While it will not rain or thunderstorm the entire forecast period, QPF continues to trend upwards. QPF for the next 7 days of 2-6" across the area. Memphis is currently in an area of 5" for the next 7 days. While it is a bit early for specifics, SPC has highlighted at least a 15% chance of severe weather on Sunday. DNM && .AVIATION... (12Z TAFS) Issued at 651 AM CDT Wed May 22 2024 A messy convective forecast over the next 30 hours, with timing and track of TSRA emerging from the southern plains and AR the primary forecast challenge. For the short term, TSRA has shown limited sustainability once it has approached the MS River overnight. That trend should continue through the morning, as the low level jet weakens. For the afternoon, convective cap will erode and the potential for more impactful surface-based TSRA will increase. Biggest question will be location. Lasted HRRR runs have trended a bit south with afternoon TSRA, from east central AR into northwest MS. This is consistent with the ECMWF model showing a slight southward shift of the upper level jet. Confidence in afternoon TSRA location and coverage is too limited to remove the TEMPO TSRA for MEM this afternoon. For the early evening, TSRA will likely be tied to convection forming over OK and north TX this morning. An MCV may emerge from this activity and eventually aid elevated TSRA organization over the Midsouth this evening. For the 12Z TAFs, will limit to a PROB30, given uncertainty in upstream storm evolution today. PWB && .MEG WATCHES/WARNINGS/ADVISORIES... AR...None. MO...None. MS...None. TN...None. && $$ PUBLIC FORECAST...DNM AVIATION...PWB