013 FXUS64 KMRX 121713 AFDMRX AREA FORECAST DISCUSSION National Weather Service Morristown TN 113 PM EDT Tue May 12 2020 .UPDATE... FOR 18Z AVIATION. && .DISCUSSION... Another day with below normal temperatures forecast. As of 10 am, temperatures across the area are generally in the 40s/50s. Cloud cover has increased across the region and there are a few light radar returns showing up. Model soundings indicate that the low- levels will remain dry throughout the day. Observations across the area confirm this with ceilings currently around 10 kft. There really is not much in the way of lift forecast today. Therefore, went ahead and decreased the chances for rainfall. Additionally, seeing some breaks in the cloud cover today. Overall, highs will generally be in the 60s today. MA && .AVIATION... 18Z TAF DISCUSSION. VFR conditions will continue to features throughout the TAF cycle. The low-levels will remain relatively dry according to model soundings. Light winds will continue with high pressure across the region. The high shifts a bit to the northeast late in the TAF cycle as a warm front lifts northward across the Lower Mississippi River Valley. Lift to the north of the boundary will be sufficient enough for a few light showers at the terminals around 09-15z. Overall, any aviation impacts would be minimal. MA && .PREV DISCUSSION... /ISSUED 321 AM EDT Tue May 12 2020/ SHORT TERM...(Today through Tonight)... The pattern this morning is highlighted by wly/nwly H5 flow with a shortwave over the Southern Plains, while an H85 warm front slowly advects northward along the I40 corridor region across AR and West TN. Moisture associated with this llv front continues to advect downstream along the H5 flow aloft which will foster increasing low/mid clouds over East TN and southwestern VA/NC through Tuesday. Therefore the fcst will initialize mostly clear, increasing to partly cloudy through mid/late morning with mostly cloudy skies to prevail into the later part of the day. Sufficient dry air will work to delay any precipitation east of the Plateau through at least the late afternoon hours, thus opted to slowly increase pops from the west through the final 12 hours of the forecast tonight. Otherwise regarding temperatures, for this morning the later timing of the increased sky cover looks to allow for modest cooling which should yield frost conditions, therefore no changes planned for the frost advisory. Max temps this afternoon will be quite similar to yesterday topping out 8-10 degrees below normal levels, with overnight lows bottoming out around 5 degrees below normal, albeit warm enough to prevent even patchy frost for most locations. CDG LONG TERM...(Wednesday through Monday night)... A warm front lifts north across the area on Wednesday with spotty light rain showers possible. With strongest low-level convergence and lift further west, limited PoPs to chance or slight chance across our area. Should have widespread cloud cover along and north of the front, but as it moves north during the day, expect some breaks to develop south of the front across SE TN and SW NC. Warmest temperatures on Wednesday will be across southern sections of the forecast area. As upper ridging builds late week, temperatures will finally be near or slightly above normal. Diurnal convective trends in cloud cover and PoPs are forecast, mainly across the higher elevations, as low- level moisture increases and an early summer pattern develops. Afternoon PoPs increase over the weekend as a weakness develops in the ridge and a cold front moves slowly southeast across the Ohio Valley. By Sunday afternoon and Monday, the weak cold front is forecast to be near the forecast area with scattered, mainly afternoon, convection. The GFS and ECMWF are in better agreement with the late weekend system, but differences still exist in the timing and southern extent of this system. For these reasons, limited max PoPs to chance for the Sunday and Monday timeframe. JB && .MRX WATCHES/WARNINGS/ADVISORIES... NC...NONE. TN...NONE. VA...NONE. && $$