153 FXUS63 KIND 011403 AFDIND Area Forecast Discussion National Weather Service Indianapolis IN 1003 AM EDT Sat Aug 1 2020 .UPDATE... The NEAR TERM Section has been updated below. && .SYNOPSIS... Issued at 144 AM EDT Sat Aug 1 2020 Low pressure over the bootheel of Missouri will push northeast across Indiana today. This will bring periods of showers...perhaps an isolated thunderstorm along with chances for heavy rain to much of the area. More rain will be expected on Sunday into Monday as a second area of low pressure crosses Indiana. Dry weather and seasonable temperatures are expected to return by the middle of the next work week as high pressure builds across the region. && .NEAR TERM /Rest of Today/... Issued at 1003 AM EDT Sat Aug 1 2020 Showers continue to drift north across central Indiana this morning with low pressure centered across the lower Ohio Valley. 14Z temperatures ranged from the mid 60s to the lower 70s in most locations. The combination of a broad upper level trough and the aforementioned surface wave set to track northeast across the area later today will bring a damp and mainly cloudy day with periodic showers into this evening. As instability increases during peak heating later today...will likely see scattered storms develop as well. The main concern remains on the potential for torrential rainfall producing localized flooding. PWATs will surge above 2 inches later today as progressively deeper moisture is advected into the region courtesy of a low level jet. Southern counties are of particular focus here with radar estimates of 4 to 6 inches since Thursday from Vincennes east towards Bedford. Already saw significant flooding issues in Martin County and near Shoals overnight. The secondary concern will be the threat for a few stronger cells late this afternoon into the early evening as the low lifts into the region. Remain uncertain how much instability can be gleaned with an abundance of cloud cover...but model soundings for late afternoon over southeast portions of the forecast area continue to advertise a sublte ramp up in BL shear and helicity within a highly saturated airmass. While the more favorable setup remains to our east over Ohio and eastern Kentucky...will need to monitor for an isolated tornado and wind threat for a few hours late day. Zone and grid updates out. && .SHORT TERM /Tonight through Monday Night/... Issued at 144 AM EDT Sat Aug 1 2020 A slow progression of the broad upper trough that stretches from Ontario to Texas is expected the next few days. This cyclonic flow in place aloft will allow several embedded short waves within the flow to push across Indiana...resulting in periodic rain showers through Monday Night. The first of these short wave within the flow is expected to push across the area tonight...accompanied by excellent lower and mid level moisture. Again overnight forecast soundings show pwats over 1.7 inches as these features slowly pass. This wave is suggested to finally depart the area by Sunday morning. Thus high pops will be required through at least Sunday morning as these upper level features pass. Forecast soundings after 18Z on Sunday show some decrease of moisture within the column...however convective temperatures are still attainable with a bit of CAPE available. Thus Pops will still needed to be continued through Sunday afternoon...but some dry time will be possible. Will stick close to the NBM temps here. On Sunday Night through Monday night the GFS and NAM continue to show the deep pesky trough axis aloft west of Indiana. This will result in Indiana continuing to be in a favorable position for precipitation. The upper flow allows yet another surface low to across Indiana on Sunday night into Monday. Although forecast soundings show much more dry air in place within the column...attainable convective temperatures with CAPE over 2000 J/KG remain in place. Thus will to continue to keep pops in place through Monday Night. && .LONG TERM /Tuesday through Saturday/... Issued at 325 AM EDT Sat Aug 1 2020 The long term period will start with a chance of showers and perhaps a thunderstorm as upper level low pressure swings through the area. Surface high pressure will quickly follow which should keep things dry mid to late week. A series of subtle disturbances in weak northwest flow very late in the period will reintroduce shower and storm chances as the weekend approaches. Temperatures will be quite mild for the time of year, largely in the 70s until late in the period, when the low 80s move back into the area. Blended initialization handled things well and required only minor adjustments. && .AVIATION /Discussion for the 01/12Z TAFs/... Issued at 713 AM EDT Sat Aug 1 2020 MVFR or worse conditions through much of the period. Low pressure will move northeast through the area today, producing plentiful showers and a few thunderstorms. Conditions will be restricted at most sites throughout the vast majority of the period. All sites but LAF are likely to get down to IFR for several hours, with MVFR ceilings otherwise. Winds will generally be northeasterly early, becoming northerly and then northwesterly with time as the low passes. For the most part, speeds should be 10KT or less. Obstructions to visibility will be possible during precipitation but will likely be variable and transient. && .IND WATCHES/WARNINGS/ADVISORIES...NONE. && $$ SYNOPSIS...Puma NEAR TERM...Ryan SHORT TERM...Puma LONG TERM...Nield AVIATION...Nield