863 FXUS63 KIND 191642 AFDIND Area Forecast Discussion National Weather Service Indianapolis IN 1242 PM EDT Fri Jul 19 2019 .UPDATE... The AVIATION Section has been updated below. && .SYNOPSIS... Issued at 311 AM EDT Fri Jul 19 2019 An upper ridge of high pressure will bring dangerously hot and humid conditions to central Indiana into the weekend. Then, a cold front will move through central Indiana late in the weekend and bring unsettled weather to the area through Sunday night. It will not be nearly as warm or humid next week as Canadian high pressure settles in in the wake of the cold front. && .NEAR TERM /Rest of Today/... Issued at 1009 AM EDT Fri Jul 19 2019 Low clouds have limited warming so far this morning...albeit slightly. Trends though showing the lower clouds beginning to mix out and expect a transition to full or nearly full sunshine by midday in most areas. 14Z temperatures already up into the mid 80s in many locations and with dewpoints in the mid and upper 70s area-wide...heat indices into the 90s as well. Not much to change for the mid morning update as the focus remains squarely on the high heat and humidity values for later today. As mentioned above...low clouds already thinning out and will continue to do so through the rest of the morning. Convective cloud debris from the weakening storm cluster over Michigan will bring some thin cirrus to northern counties over the next few hours but should do little to deter warming. Low level thermals remain on point to bring max temps into the mid 90s over much of the area by late afternoon. Do expect dewpoints likely fall back a bit from current readings as boundary layer mixing increases later...but still should see heat indices top out from 105 to 110. Zone and grid updates out. && .SHORT TERM...(Saturday through Sunday night) Issued at 311 AM EDT Fri Jul 19 2019 Models in good agreement that the heat and humidity will hang around through at least Saturday and likely Sunday. Models keep the upper ridge over the area Saturday. But the flow upstream will begin to buckle late in the weekend and allow a cold front to drop down across the area late Sunday and Sunday night. The 00z NAM and 00z GFS both look a bit to sharp and progressive considering the strength of the ridge. The ECMWF and GEFS area was similar and favored. At any rate, the cold front will interact with the heat and humidity and touch off scattered to widespread convection Sunday and Sunday night per the blend. Could see a few showers or thunderstorms Saturday night over northern sections. The Excessive Heat Warning looks good through at least Saturday with highs in the 90s and heat indices to near 110. Confidence is not as good regarding temperatures Sunday convection timing and coverage will be a factor. && .LONG TERM /Monday through Friday/... Issued at 234 AM EDT Fri Jul 19 2019 A welcome break is on the horizon. A frontal zone will move through the area late in the weekend into early Monday, producing some chances for thunderstorms, but also reducing temperatures as the upper level ridge weakens and surface high pressure builds into the area. Much of the work week will be significantly milder with dry weather, clear or mostly clear skies, and high temperatures beginning the week in the low 80s, climbing back toward the mid to upper 80s by later in the week. && .AVIATION /Discussion for 191800Z TAF Issuance/... Issued at 1242 PM EDT Fri Jul 19 2019 Mainly VFR conditions through the forecast period. High pressure at the surface and ridging aloft will maintain quiet condition into Saturday. A cu field has developed early this afternoon and will linger into the early evening before diminishing. While some ceilings have been below 3kft...expect cu bases to settle between 4k and 5kft later this afternoon. Skies will become mainly clear tonight into Saturday. Southwest winds will be around 10kts with an occasional higher gust. Expect winds to weaken to 5-10kts overnight into Saturday morning. && .IND WATCHES/WARNINGS/ADVISORIES... Excessive Heat Warning until 8 PM EDT Sunday for INZ021-028>031- 035>049-051>057-060>065-067>072. && $$ SYNOPSIS...MK NEAR TERM...Ryan SHORT TERM...MK LONG TERM...Nield AVIATION...Ryan