761 FXUS63 KIND 110600 AFDIND Area Forecast Discussion National Weather Service Indianapolis IN 200 AM EDT Sun Oct 11 2020 .UPDATE... The SYNOPSIS...NEAR TERM and SHORT TERM Sections have been updated below. && .SYNOPSIS... Issued at 159 AM EDT Sun Oct 11 2020 Remnants from Hurricane Delta are expected to push across Kentucky today. Rain with this system is expected to remain south of Indiana...however some cloudiness will prevail across Indiana today. A quick moving cold front will then sweep across Indiana from the plains on Monday afternoon...bringing chances for showers or a thunderstorm. Cooler and less humid air will arrive for Tuesday and Wednesday as high pressure moves into the Ohio Valley. Another cold front passing late in the work week will bring more chances for light rain along with even cooler temperatures. && .NEAR TERM /Today/... Issued at 159 AM EDT Sun Oct 11 2020 Surface analysis early this morning show low pressure associated with Delta remnants over Mississippi. A weak cold front was found stretching across Pennsylvania...across OH and Indiana to Central Illinois. High pressure was found across the Great Lakes. Light NE surface flow was in place across Indiana. GOES16 shows high cloud associated with Delta in place across the south and eastern parts of the state...while some lower strato-cu was found in the wake of the front over Northern Indiana. Models today show the northeast progression of Delta remnants along with the southerly progression of the cold front to the north. Aloft...the remnants were cut off from the main flow aloft...which was a ridge in place over the Great Lakes. Meanwhile within the lower levels...the weak cold front to the north is expected to push slowly southward...keeping much of the moisture associated with the remnants south of Central Indiana. Forecast soundings through the period along with time heights reveal a dry column across the area today. Thus with our sweeping cold front and all of the best moisture associated with the remnants southeast of Indiana...will trend toward a dry forecast today with partly sunny skies. Given our expected cloud cover...will trend highs at or below the NBM. && .SHORT TERM /Tonight though Tuesday Night/... Issued at 159 AM EDT Sun Oct 11 2020 Models remain in good agreement tonight that Delta Remnants will be exiting the region...along with the ridging in place aloft over the Great Lakes. A deeper trough is expected to arrive over the Western Plains states which will be our weather feature for Monday. However...for tonight we will be caught between the departure of the upper ridge and the arrival of the approaching trough to the west. Again time heights and forecast soundings continue to show a dry column overnight with ongoing subsidence. Thus will trend toward a partly cloudy sky and lows at or below the NBM. GFS and NAM then suggest a strong upper trough...slightly negatively tilted...pushing across Indiana on Monday afternoon and Monday Night. A sharp cold front was associated with this system and will push across Indiana on Monday afternoon. Ahead of the front moderate southerly flow looks to be in place allowing dew points to reach upper 50s. Forecast soundings suggest saturation on Monday afternoon with pwats of 1.22 to 1.4 inches. Given our favorable forcing dynamics aloft along with sufficient moisture in place...confidence is high for at least some light measurable precip as the along and ahead of the frontal passage. Thus will trend pops at or above the NBM. Given the lack of full day of heating...will trend highs at or below the NBM. Strong subsidence and dry air arrives across the area in the wake of the frontal and upper trough. Forecast soundings on Monday night dry out with strong subsidence in play and remain dry through Tuesday with unreachable convective temperatures. Quick Pacific flow remains in place across the region in the wake of the trough...limiting moisture and blocking high pressure across the southern states will prevent the arrival of any gulf moisture. Thus have will trend toward mostly clear nights and a mostly sunny Tuesday with temps at or below the NBM given the weak cold air advection in play. && .LONG TERM /Tuesday night through Saturday/... Issued at 250 PM EDT Sat Oct 10 2020 The main highlights to the extended will be related to a fairly strong cold front that will move through central Indiana from northwest to southeast Thursday. Timing with the 12z runs looks to be around 09z-18z. Model rh and omega time sections along with mean level rh and vertical motion fields support the chance PoPs that the NBM just introduced for the first time, although a sustained good Gulf inflow is absent. Would not rule out a shower or two ahead of the cold front Wednesday night, but best chances look to be on Thursday with the front. Still, with lack of impressive Gulf inflow, the small chance blend PoPs look good then. The showers should exit Thursday night behind the front. Instability progs hint at perhaps 100 J/KG CAPE but will not jump the gun just yet regarding thunder. Looking at thermal progs in the wake of the cold front, temperatures will drop back to below normal next weekend as high pressure builds in and in despite of drying column supporting a good degree of sunshine. Prior to the front arriving, high pressure will provide one more dry day with above normal temperatures Wednesday in the 70s. In contrast, highs Saturday 55 to 60, a full 10 degrees below seasonable highs 65 to 70. && .AVIATION /Discussion for 110600Z TAF Issuance/... Issued at 1139 PM EDT Sat Oct 10 2020 Ceiling restrictions will impact the terminals beginning in the predawn hours Sunday continuing through about midday. The remnants of Delta were centered over northeast Mississippi late this evening with the broad cloud shield well out to the northeast across much of the Ohio Valley. The system will track E/NE to eastern Tennessee by Sunday evening. High level clouds will remain across the area into the overnight before deeper moisture advects in from the south prior to daybreak. Model soundings and RH progs show an increase in boundary layer moisture from the east overnight with MVFR and some IFR ceilings developing during the predawn hours. KBMG and KIND are likely to be impacted by a period of IFR ceilings around and shortly after daybreak with scattered pockets of lower ceilings elsewhere. Any light showers are expected to remain to the southeast of the terminals Sunday morning. Ceilings will lift back to VFR by midday with the onset of mixing through the boundary layer and the deeper moisture plume shifting off to the east during the afternoon. Some scattering of the clouds is expected late Day Sunday and through the evening but the development of a shallow but steep inversion late Sunday night will enable the lower stratocu deck to reestablish. Light and variable winds tonight will transition to northeast over the next few hours...remaining between east and northeast through early Monday. && .IND WATCHES/WARNINGS/ADVISORIES... NONE. && $$ SYNOPSIS...Puma NEAR TERM...Puma SHORT TERM...Puma LONG TERM....MK AVIATION...Ryan