Area Forecast Discussion
Issued by NWS Northern Indiana
Issued by NWS Northern Indiana
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686 FXUS63 KIWX 192325 AFDIWX Area Forecast Discussion National Weather Service Northern Indiana 725 PM EDT Thu Sep 19 2024 .KEY MESSAGES... - Drought conditions will continue to worsen across the area with the best chance, albeit low confidence, coming Sunday night into Monday chances for much needed rainfall. - Above normal temperatures will persist a few more days, before cooling somewhat into next week. && .DISCUSSION... Issued at 218 PM EDT Thu Sep 19 2024 Region continues to be dominated by high pressure to the east that will have little in terms of dynamics to displace it until early next week. A weak cold front will edge east over the next 24 to 36 hours, slowly washing out over time as it becomes orphaned from the better overall flow and dynamics. Dewpoints ahead of the front are in the mid 60s, with these attempting to make a run at the area, but are likely to be mixed out somewhat given the antecedant dry conditions and shallow nature of the moisture (as depicted by 12Z KILX and KDVN soundings). While upper level flow isn`t horrible and DCAPES AOA 1000 J/KG will exist courtesy of the EML, low level instability will be very limited resulting in some cu development tomorrow afternoon along with an outside chance of a few cells gaining some height, but struggling to organize in any fashion. In addition, upstream convection may leave cloud cover around in the morning to limit heating. Marginal risk was introduced earlier for a portion of the area, mainly for the "pulse" nature of any storms that somehow can get some development. While possibly overdone, previous shift layout of pops in the NW Fri afternoon isn`t unreasonable at this point pending impacts from upstream convection. Will make a few minor tweaks but overall leave alone. Did remove slight chc pops Fri evening as any activity that forms should quickly diminish around 00Z Sat. Above normal temperatures (well into the 80s) will persist into Saturday, with some locally cooler temps possible tomorrow if cloud cover or precip coverage is more than currently forecasted. Upper low currently located off the SW California coast, will move slowly ENE over the weekend, reaching Iowa by 12Z Mon. Somewhat better moisture influx will accompany this to bring hopefully improved chances for showers and storms as early as Sunday night, possibly lingering into Tuesday as northern stream wave drops in and lingers into Wednesday. Confidence remains low on specific details including timing and how widespread the precip may be. Model blends continue to bring in likely pops and this is climatologically and logically unreasonable at this point. Have limited pops as best I can while remaining collaborated with surrounding offices. Cooler temperatures will arrive starting Sunday with highs by the middle of next week in the low to mid 70s. It should be stated that even with the chances for rainfall Sun-Tue, overall drought conditions will remain unchanged, if not worsen for many areas as amounts won`t be enough to remove the deficits in place. Last, but not least, as noted by the overnight forecaster, trend towards drier conditions should occur behind the upper low as it shifts far enough east late Wed into Thu. && .AVIATION /00Z TAFS THROUGH 00Z SATURDAY/... Issued at 725 PM EDT Thu Sep 19 2024 Dew points are expected to level off overnight in the mid 50s as temperatures slowly fall into the upper 50s and low to mid 60s. This miss for cross-over temperatures likely yields only patchy ground fog in the FWA area. This is a moisture axis makes its way into the area for Friday. Winds become more southwesterly during the day Friday and increase chances for showers during the midday and afternoon hours. At this point, it`s hard to have confidence in chances for rain given antecedent dry conditions, but the chance is at least there. With all of this in mind, will lean prevailing VFR through the period at both sites. && .IWX WATCHES/WARNINGS/ADVISORIES... IN...Air Quality Alert until midnight EDT /11 PM CDT/ Friday night for INZ005-012>015-022-023-104-116-204-216. Air Quality Alert until 11 PM CDT this evening for INZ103-203. OH...None. MI...None. MARINE...None. && $$ DISCUSSION...Fisher AVIATION...Roller