


Area Forecast Discussion
Issued by NWS Indianapolis, IN
Issued by NWS Indianapolis, IN
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333 FXUS63 KIND 272313 AFDIND Area Forecast Discussion National Weather Service Indianapolis IN 713 PM EDT Thu Mar 27 2025 .KEY MESSAGES... - Showers and scattered thunderstorms expected, especially late tonight, with briefly heavy downpours and small hail possible with the strongest cells - Frequent wind gusts Friday of 35-45 MPH with locally higher gusts possible - Highs a few degrees shy of records Friday, with continued warmth through the weekend - Wet and unsettled pattern developing with periodic rain and storm chances through Monday - Strong to severe storms expected Sunday afternoon and evening && .SHORT TERM (This evening through Friday)... Issued at 310 PM EDT Thu Mar 27 2025 A warm front will push northward through the area tonight, bringing showers and a few thunderstorms to central Indiana, along with much warmer conditions for Friday, along with strong winds. Scattered showers are ongoing, in the area and points west, primarily associated with isentropic lift along the intensifying warm frontal zone to our southwest. Significant dry air in the low levels has limited the ability of these showers to reach the ground, especially the further removed from the front they are. This will change overnight as the front lifts through the region, along with a reintensifying west/southwesterly 35-45KT low level jet. Some modest instability should be available, though convection is highly likely to be elevated. This will limit threats from scattered storms later tonight to briefly heavy downpours and perhaps small hail with the strongest cores, along with lightning of course. This activity will gradually exit the area Friday morning as the warm front continues to lift northward. Focus will then shift to winds for Friday, in what should be a very warm, if not near record, day for central Indiana. Flow in the lowest 3-5KFT will be quite strong, as the low level jet remains 50+KT through much of the day. Depending on degree of clearing and depth of mixing, a significant proportion of this momentum may be able to mix to the surface, and frequent gusts of 35- 45 MPH appear likely from midday through the afternoon hours. Localized gusts to 50 MPH cannot be ruled out, and depending upon guidance trends, a wind headline may be needed, but will hold off for now in collaboration with neighboring offices. Will message with an SPS and other venues as appropriate. High temperatures tomorrow with good insolation, strong warm advection, and what should be good mixing in broad southwesterly flow will be well into the 70s, and perhaps push 80 in spots. Record highs for the day range from the mid 70s to mid 80s across the area. Current forecast highs will fall a couple/few degrees shy of those numbers, but could easily reach them in spots if highs overperforming. && .LONG TERM (Friday night through Thursday)... Issued at 310 PM EDT Thu Mar 27 2025 A low-amplitude trough is expected to emerge into the Great Plains at the beginning of the long range. This feature will then induce cyclogenesis across the Midwest which may lead to increased severe weather potential as Indiana will firmly be in the system`s warm sector. SEVERE WEATHER POTENTIAL AND DETAILS By Sunday afternoon, guidance generally has surface low pressure located somewhere near the Illinois and Wisconsin border. There remains considerable model differences regarding the evolution and timing of this feature. These differences have a greater impact on the mesoscale environment and so confidence is HIGHER for the overall pattern rather than the small details that could have a big impact on severe weather potential. With that being said, in all model scenarios Indiana is within the system`s warm sector with a potent south-southwest jet streak overhead or nearby. Thermal profiles show steep lapse rates and sufficient instability for thunderstorms. Models show sufficient shear (over 50kt) for organized convection and potentially strong thunderstorms. Hodographs are generally long and straight as surface winds are mainly depicted to be out of the southwest. Based on current information, wind and hail would be the primary hazards on Sunday, with a lower threat for tornadoes. Tornadoes are still possible, as near-surface buoyancy looks to be in place as well as shear in the 0-1km layer. The tornado threat could increase should the system evolve in such a way that leads to increased curvature in the low-level hodographs. Stay tuned for updates as model consensus increases and these finer-scale details become visible. Temperatures are likely to be well-above average as long as we`re in the system`s warm sector, before trending downward after its attendant cold front passes through on Monday. MONDAY ONWARD A progressive synoptic-scale pattern looks to continue with another trough modeled to arrive midweek. Even greater model uncertainty exists regarding this system, but most guidance shows it to some extent. Confidence is therefore higher for broad PoPs but that`s about it. Yet another trough is depicted by ensemble guidance arriving next weekend, but with still lower model agreement we`ll just leave it at that. Overall, an active pattern looks to be upon us with repeated weather systems passing through. && .AVIATION (00Z TAF Issuance)... Issued at 713 PM EDT Thu Mar 27 2025 Impacts: - Mainly VFR this TAF period. - Showers with an isolated thunderstorm possible late tonight. - Non-convective low level wind shear possible late tonight. - Strong gusty winds late in the period into Friday afternoon. Discussion: Radar shows scattered light rain showers north and south of the TAF sites, failing to impact any of them. VFR cigs remained across the area, as a warm front was approaching from the southwest. Overnight, a warm front along with strong isentropic lift is expected to push north across the TAF sites. HRRR suggests a window of mainly 04Z-11Z pushing showers and isolated storms across the TAF sites. Thus have focused a VCSH period at that time. Forecast soundings shows dry lower levels, thus mainly VFR cigs will be expected with the precipitation. As the front moves through the area late tonight, flow aloft will strengthen and turn southwesterly before surface flow does so, and this will lead to a period w/ fairly significant speed and directional shear. A strong pressure gradient amid southwest flow is expected on Friday. This will lead to gusty winds, possibly reaching to around 35 knts on Friday afternoon. && .IND WATCHES/WARNINGS/ADVISORIES... None. && $$ SHORT TERM...Nield LONG TERM...Eckhoff AVIATION...Puma