624 FXUS63 KIND 242309 AFDIND Area Forecast Discussion National Weather Service Indianapolis IN 709 PM EDT Fri May 24 2019 .UPDATE... The AVIATION Section has been updated below. && .SYNOPSIS... Issued at 242 PM EDT Fri May 24 2019 High pressure east of Indiana will continue to provide mainly dry weather tonight across central Indiana. Rain chances will return to central Indiana on Saturday and persist through the holiday weekend. This is due to several upper level weather disturbances expected to pass across Indiana this weekend...along with a pesky and persistent stationary boundary lingering across Central Indiana. Chance for rain are expected to continue through the middle of next week. && .NEAR TERM /Tonight/... Issued at 242 PM EDT Fri May 24 2019 Surface analysis early this afternoon shows high pressure in place across Tennessee...with a a frontal boundary lingering across Central Indiana. Surface flow across Indiana was from the southwest across the southern half of the forecast area...and easterly flow was present across the the northern half. Plenty of warm and humid air was in place south of the boundary with dew point temps in the 70s. Radar upstream shows a cluster of thunderstorms over Western Illinois and a tornado watch has been issued for that area. Thickness propagation suggest a general westward progression of the storms. Furthermore the boundary in place across the area may act as focus of lower level convergence. HRRR weakens this system upon approach...but not sure how likely that is. CAPE across the area is approaching 2500 j/kg along and south of the boundary that is bisecting the forecast area. Forecast soundings this afternoon and evening reveal a conditionally unstable column and convective temps are being reached. Thus will continue to watch closely the propagation and evolution of the approaching storms. Chances for late afternoon and evening storms appear warranted given the boundary and instability in place along with the approaching system. As daytime heating wanes...convection is expected to come to an end this evening. Models suggest ridging aloft over the area also begins to push east of the area. Otherwise any forcing dynamics appear to push north of Central Indiana and forecast soundings and time sections appear dry. Thus will trend to ward a dry forecast after 02Z or so. Will stick close to the blends on temperatures. && .SHORT TERM /Saturday through Monday/... Issued at 242 PM EDT Fri May 24 2019 Confidence for rain during this period has increased. GFS and NAM now show an flattening out of the upper flow from Saturday through Monday. This results in several short waves passing across Indiana through Monday. Meanwhile within the lower levels a stationary frontal boundary is expected to bisect the state for much of the period. Forecast soundings show convective temperatures able to be reached each day through Monday. Each afternoon CAPE exceeds 2000 J/KG and Pwats surge over 1.5 inches. Should several rounds of precip occur...this ongoing pattern of multiple short waves passing across our stationary front could lead to a flash flooding threat. Thus precip chances will be needed each afternoon and evening through Monday. Confidence remains to be growing for precip chances on Sunday afternoon and the GFS and NAM both are hinting at an organized short wave approaching Indiana during the afternoon hours. Will trend lows warmer than the model blends given the expected clouds...rain and humid air mass. Will stick close on highs expect across the southern parts of the forecast area which will be located deeper within the warm sector. Will trend a little warm at those spots on highs. && .LONG TERM /Monday Night through Thursday Night/... Issued at 218 PM EDT Fri May 24 2019 Showers will become confined to the northeast quadrant of central Indiana as a warm front pushes northward on Monday night. At that point, dry conditions will prevail for Tuesday, but central Indiana will fall into a warm sector and strong southwest winds will push daytime highs into the mid to upper 80s. At that point, focus will turn to shower and thunderstorm chances through mid week as a cold front moves through the region. Temperatures will fall closer to normal for Wednesday and Thursday in the wake of that front. && .AVIATION /Discussion for 250000z TAF issuance/... Issued at 702 PM EDT Fri May 24 2019 VFR through the night. Chances for rain and some storms will arrive on Saturday, moving from west to east across the sites during the late morning/afternoon. For now will just include a VCSH during the most likely time of showers, and will refine this and consider the addition of thunder when the threat is more imminent. For winds should see them remain up overnight in the 5 to 10 kt range but gusts should fall off with sunset, and direction should be around 180 to 230. Then Saturday they will be out of the southwest and increase in speed to around 8 to 13 kts with gusts to around 20 to 25 kts during the afternoon. Expect VFR diurnal cu around 3500 to 5000 ft from late morning through the afternoon on Saturday. && .IND WATCHES/WARNINGS/ADVISORIES... NONE. && $$ SYNOPSIS...Puma NEAR TERM...Puma SHORT TERM...Puma LONG TERM....TDUD AVIATION...CP