Area Forecast Discussion
Issued by NWS Indianapolis, IN
Issued by NWS Indianapolis, IN
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024 FXUS63 KIND 242002 AFDIND Area Forecast Discussion National Weather Service Indianapolis IN 302 PM EST Mon Nov 24 2025 .KEY MESSAGES... - Rain expected tonight through Tuesday night - Turning colder beginning Wednesday into next weekend - Watching Saturday into the following week for strong storm systems to bring rain, snow, and large temperature swings to Indiana && .SHORT TERM (This evening through Tuesday)... Issued at 302 PM EST Mon Nov 24 2025 Mostly cloudy to cloudy conditions will persist through the remainder of the afternoon. Some weak lift may produce some sprinkles or light rain, mainly in the far southwest/west. Will keep some low PoPs there. Tonight, an upper trough will approach the area from the west, and an area of surface low pressure will move into Illinois. A surface trough/warm front will move north into central Indiana. Upper and low level jets will also move into the area. The low level jet will bring in additional moisture. The lift from the above features combined with the plentiful moisture will bring rain to central Indiana. Current timing of the most coverage of rain is overnight, when the low level jet kicks in. Will go high PoPs all areas. Instability remains south of the area, so will continue to not mention thunder. Low temperatures will generally be in the 40s. Stronger lift and deeper moisture will exit the area to the east during the morning as the upper trough and surface low exit to the east. Will have likely or higher PoPs early in the day over the eastern two-thirds of the area, with PoPs then diminishing from west to east during the morning. Low level moisture will linger through Tuesday afternoon. There looks to be some weak lift in this layer, which should result in drizzle from time to time. Warm advection should push temperatures into the middle 50s to near 60. && .LONG TERM (Tuesday night through Monday)... Issued at 302 PM EST Mon Nov 24 2025 A significant pattern change is expected this week. Synoptic analysis shows a progressive split flow pattern over the CONUS. Flow tends to diverge over the intermountain west before re- converging over the Midwest. A vort max within the southern jet axis is currently ejecting into the Plains, and will be the source for the rainfall expected tonight into tomorrow. This system is expected to strengthen substantially over the Great Lakes, driving a potent cold front southward on Wednesday. Deep troughing then takes hold over the eastern third of the CONUS which persists into the weekend. Wednesday into Thursday Of particular interest is Wednesday`s cold front. This front will be the first stage of our pattern change, with scattered showers along the front itself and strong cold air advection and gusty winds behind it. Wednesday`s highs likely peak before sunrise, falling continuously through the day. Combined with winds in the 20-30mph range, it will feel rather unpleasant. Additionally, some scattered flurries are possible Wednesday since cold air advection aloft will lead to some low-level instability. Winds remain on the breezy side through Thanksgiving as a relatively tight MSLP gradient persists across the Midwest, though we can be thankful that it does not appear to be as windy as Wednesday. That may be of little consolation since highs may struggle to reach freezing. Wind chills into the 20s even during the afternoon appears likely. Friday through Sunday Troughing and cooler than average temperatures are expected to continue into the weekend. Simultaneously, a storm system is modeled to take shape out west as a shortwave trough comes ashore over the Pacific Northwest late Thursday. After that, the situation becomes tricky with guidance diverging considerably. A wide range of scenarios are possible, ranging from a warming trend with rain showers to continued cold with accumulating snowfall. The eventual outcome will be determined by how the western trough evolves. The GFS, for instance, generally allows the trough to dig southward with slow progression eastward. This allows the system to lift northward later with broad warm flow ahead of it. This would bring about a warmer and rainier solution for much of Indiana, with perhaps some snow at onset or further north. On the contrary, the ECMWF/GEM take the shortwave and allow it to dive southeastward within the flow around the larger and retreating eastern trough. This would allow less in the way of warm air advection ahead of the system and thus lead to a snowier solution. Taking a look at the various teleconnections we see a generally neutral trending negative PNA, with neutral AO/NAO. Negative PNA typically favors persistent western troughing / eastern ridging, which both the GEFS and EPS ensembles do show later in the forecast period. Unfortunately, this would mainly be after our potential storm system which occurs during the transition from troughing to ridging over the eastern US. Though that does point to a gradual warming trend after the weekend storm with a potentially active storm track remaining in place into December. For now, both sets of guidance are in decent agreement showing an initial round of snow Friday night/early Saturday with the first push of warm air advection. Model uncertainty increases thereafter, though we`ll maintain a slow transition to mainly rain until guidance comes into agreement on how strong and prolonged the warm air advection is. Stay tuned for updates. && .AVIATION (18Z TAF Issuance)... Issued at 1200 PM EST Mon Nov 24 2025 Impacts: - Some improvement at KHUF/KBMG this afternoon and evening - Rain developing this evening with deteriorating conditions to IFR and lower tonight at all sites Discussion: Fog and stratus will gradually lift/mix out at KHUF/KBMG this afternoon into the evening. Mid and high clouds will continue into the evening elsewhere. A system will bring rain tonight into Tuesday morning, with drizzle possible after the rain ends Tuesday. Conditions will deteriorate to IFR and lower overnight, with these conditions continuing Tuesday. Southeast winds into tonight will veer to south and southwest on Tuesday. && .IND WATCHES/WARNINGS/ADVISORIES... None. && $$ SHORT TERM...50 LONG TERM...Eckhoff AVIATION...50