Forecast Discussions mentioning any of "ACARS" "MDCRS" "AIRCRAFT" "TAMDAR" "AMDAR" "WVSS" received at GSD on 08/18/19

Area Forecast Discussion
National Weather Service Louisville KY
953 PM EDT Sat Aug 17 2019 .Forecast Update... Updated at 953 PM EDT Sat Aug 17 2019 Have been keeping an eye on strong to severe storms that have blown up in southern Illinois over the past few hours. It appears that these storms and other overnight convection should stay to the west and north of southern Indiana and central Kentucky closer to better instability and low level jetting. && .Short Term...(This evening through Sunday) Updated at 240 PM EDT Sat Aug 17 2019 Near-term models today have handled this afternoon`s convection poorly, especially when compared to how the overnight models and even yesterday`s runs. AMDAR sounding out of Louisville now showing a little bit of airmass modification in the 900-600 mb layer...enough so to justify the more unstable airmass causing the storms just to the west/left of the Ohio River and the lack of convection to the east/right. Will continue to see isolated to widely scattered storms develop the rest of the afternoon hours, mainly along and north of I-64...again as that airmass modification goes on...but soon cloud cover will start to limit available instability. All activity should shut down with that loss of instability and then sunshine this evening. Another mid-level disturbance is forecast to cross the Midwest late tonight, but this one should be far enough north of our region to keep the storm track well north of us. That more northern track, accompanied by a more southwest wind tomorrow could push our temperatures to the warmest of the season so far. Heat indices won`t be as high as during the July spell, but they still will top out around 100 degrees for many locations. .Long Term...(Sunday night through Saturday) Updated at 222 PM EDT Sat Aug 17 2019 The upper level pattern going into Monday will feature a large ridge building into the southern Plains and modest zonal flow over the upper Midwest into New England. Upper level flow will be relatively weak over most of our region and devoid of any notable shortwaves and/or disturbances. This should result in a hot and mostly dry forecast. A strong, upper level trough will begin digging into the eastern CONUS on Tuesday and force the Plains ridge to retrograde some to the west. A surface cold front associated with the trough will begin approaching the region on Wednesday. This will result in a period of unsettled weather with increased shower and storm chances. Showers and storms could linger into Thursday and Friday depending on how quickly the front moves through, though chances for any precipitation that late in the week would likely be confined to southern Kentucky. Slightly cooler temperatures and lower dewpoints will then move in behind the front. && .Aviation...(00Z TAF Issuance) Updated at 729 PM EDT Sat Aug 17 2019 VFR conditions expected throughout this TAF cycle as surface high pressure sits over the Ohio Valley. Expect light southerly winds overnight with intermittent cirrus streaming through the region. With HNB having received a bit of rain earlier, there is a chance that some brief MVFR vis could occur near sunrise. But no model data is suggesting this as boundary layer winds are projected to be strong enough to prevent any fog development. Have decided to leave any mention of reduced vis out of HNB`s TAF, but will keep an eye on this for future TAF issuance. Sunday afternoon will see winds pick up out of the southwest with gusts in the upper teens possible at SDF and HNB. && .LMK WATCHES/WARNINGS/ADVISORIES... IN...None. KY...None. && $$ Update...13 Short Term...RJS Long Term...DM Aviation...CG