350 FXUS63 KIND 141000 AFDIND Area Forecast Discussion National Weather Service Indianapolis IN 600 AM EDT Mon Apr 14 2025 .KEY MESSAGES... - Major flooding continues on the lower White River - Breezy and Partly Sunny Today; Becoming Mostly Cloudy tonight and colder. Small, Isolated shower chance southeast - Warming trend towards the end of the week with additional thunderstorms on Friday && .SHORT TERM (Today and tonight)... Issued at 256 AM EDT Mon Apr 14 2025 Synopsis: Surface analysis early this morning shows Low pressure over Northern IL, moving northeast. A cold front was trailing the low, stretching SW to Central MO. This placed central Indiana within the warm sector, with southerly winds in place across the area. GOES16 shows mid and high clouds flowing across Central Indiana, but regional radar was dry with this system. Dry lower levels were indicated by the high dew point depressions, near 20F. Aloft, water vapor showed a strong ridge in place over the eastern Great Lakes, while a trough was found over the upper midwest. Mainly a zonal flow was in place across the Plains states, flowing into Indiana and Ohio, with high clouds and Pacific moisture within that flow. Today - Models suggest the trough over the upper midwest will buckle the zonal flow to the south, slowly allowing the trough to sag into IA/MN and NB. This will keep the steady stream of high cloud over Indiana through Much of the day. Meanwhile within the lower levels the surface low and associated cold front will sweep northeast, pushing the front across Central Indiana during the morning hours. Forecast soundings fail to show saturation within the lower levels as the surface front passes and convective temps remain too high. HRRR does show some shower/storm devlopment over far SE Indiana and SW OH, but this should not impact Central Indiana. Thus we will just expect another partly sunny day with filtered sunshine across the area. Given the arrival of westerly winds this morning and cold air advection this afternoon, highs in the middle and upper 60s may be reached in early afternoon before falling to the lower 60s by late afternoon due to the cold air advection. Tonight - The previously mentioned upper trough is expected to settle across Indiana and the Great Lakes. Meanwhile at the surface, westerly winds are expected to persist as surface high pressure settle across the plains and low pressure lingers over NE Ontario. This will once again place Indiana within an area of subsidence, and moisture will be lacking. Time heights show dry upper levels but some saturation is found within the lower levels overnight and diurnal cooling and cold air advection suggest overnight stratocu development. Thus dry weather is expected overnight, but skies will become mostly cloudy. A colder night will be expected given the cold air advection, with lows in the lower 40s. && .LONG TERM (Tuesday through Sunday)... Issued at 256 AM EDT Mon Apr 14 2025 Tuesday Through Thursday. Quieter but breezy conditions are expected for Tuesday with a low- end potential for a few showers as colder air works in aloft and creates some low-end instability in the mid-levels. Moisture will be marginal, but as often is the case on the backend of more significant upper level lows, there will be just enough lift to squeeze out a few showers. Tight pressure gradients combined with the aforementioned cold air aloft will allow for the boundary layer to deepen to 5-6kft and allow for the mixing down of wind gusts to around 30-35 mph with isolated gusts up to 40 mph towards Muncie where the LLJ will be maximized. Broad northwesterly flow will continue into Tuesday night with the potential for a return to frost Tuesday with lows in the 30s, but there remains a lot of uncertainty as to how favorable conditions will be for frost with the potential for both clouds and winds remaining elevated through the overnight hours. Broad ridging will dominate the weather pattern for the middle of the week with the upper level jet remaining well north of the forecast area. Good flow from the Gulf will help to bring a return to warmer than normal temperatures and allow for occasionally breezy conditions Wednesday and Thursday. Friday Through Sunday. Focus then shifts to the conditional threat for a few strong to severe storms on Friday as the continued flow from the Gulf brings temperatures to near 80 and dewpoints into the low 60s. This warm and moist air will interact with an upper level trough moving in from the northwest with a seasonably potent blast of cold air behind it. Showers and storms are expected to initiate along the southward moving cold front with both dynamics and thermodynamics favorable for a few strong to severe storms. Details remain very uncertain with model differences on both the timing of the system and the strength of the cold air behind the system, but a low-end severe threat seems reasonable at this time. Cooler air then will move in for Saturday behind the front but this cooldown will be brief as a much stronger low will be developing near the Four Corners region late Saturday into Sunday before pushing into the Midwest early next week bringing additional severe weather threats to the Central US states. && .AVIATION (12Z TAF Issuance)... Issued at 559 AM EDT Mon Apr 14 2025 Impacts: - Westerly wind gusts to 20kts this afternoon Discussion: VFR conditions expected through the TAF period with partly to mostly cloudy skies at around 080 through the day today. Winds will continue to shift westward over the next 2 hours with wind gusts to 20kts after 15Z which will continue through sunset. Winds will then remain at around 8-12kts through the overnight hours tonight before gusting again to as high as 30kts tomorrow. && .IND WATCHES/WARNINGS/ADVISORIES... None. && $$ SHORT TERM...Puma LONG TERM...White AVIATION...White