847 FXUS63 KIND 170209 AFDIND Area Forecast Discussion National Weather Service Indianapolis IN 1009 PM EDT Fri Oct 16 2026 .KEY MESSAGES... - Patchy frost possible late tonight in sheltered locations north of Indianapolis - Widespread frost Saturday night with sub-freezing temps possible - **Freeze Watch** north and east/southeast of Indianapolis Saturday night into early Sunday morning && .FORECAST UPDATE... Issued at 1006 PM EDT Fri Oct 16 2026 Gloomy, at times windy, transition into autumn will be waning through the overnight...as strong, broad, and amplified polar surface high pressure settles over most of the CONUS...with its positively-tilted axis from the southern High Plains to Chicagoland, advancing close enough to central Indiana to drop sustained winds under 10 mph by dawn. At least partial clearing has already begun over the northwestern half of the CWA, with SCT/BKN decks expected to continue west of Lafayette/Crawfordsville from fetch off of Lake Michigan that may allow a stray RW over these few western counties. Carroll County and vicinity may be in a small area east of these lake clouds, yet near the pre-dawn waning winds...to allow patchy frost in the few most protected areas, although chances/confidence too low for any corresponding headline. Dewpoints continuing to drop into the mid- to upper 30s by 12Z will guide overnight minimum temperatures, expected to range from mid-30s north/east of Marion County...to around 40F across the region's southern-third and in downtown Indianapolis. Freeze Watch continues for zones north/east/southeast of Indianapolis Saturday night. && .DISCUSSION (This evening through Friday)... Issued at 301 PM EDT Fri Oct 16 2026 Cold air advection is ongoing following a cold frontal passage last night. Temperatures have been falling through the daylight hours as northwesterly winds gust to between 20-30 mph. Little additional temperature recovery is anticipated and our highs for the day are likely to have already occurred. Persistent low cloud cover will help today feel quite miserable after the prolonged stretch of warm weather we have seen. Aloft, a potent but positively-tilted trough is diving in from the north. This feature will steepen lapse rates while propelling a secondary front southward. Lapse rates could steepen even more immediately down wind of Lake Michigan as flow passes over the warmer water, increasing boundary layer temps by a few degrees. A band of scattered showers is likely this evening in conjunction with these features. Best timing brings showers to the Lafayette area around 5-6pm with activity reaching Indy by 7-8pm, and eventually Bloomington by 9-10pm. Shower activity could be briefly heavy, but overall rainfall amounts will be under a tenth of an inch. Winds are expected to become northerly behind the secondary front. Speeds and gusts are also expected to increase, with gusts this evening between 25 to 35 mph possible. The upper trough departs overnight and a quick reduction in winds appears likely tonight. Guidance is in good agreement showing speeds dropping to under 15 mph by sunrise. Combined with clearing skies, winds may become calm enough to allow for patchy frost north of Indy overnight mainly in sheltered areas. Overall, our current thinking is winds remain elevated just enough to prevent widespread frost. As such, a Frost Advisory was not issued for tonight. Nevertheless, we introduced the mention of patchy frost in rural areas over the northern parts of our CWA. As surface high pressure builds in on Saturday, the clearing trend continues with winds becoming calm by sunset. Temperatures likely remain suppressed somewhat due to waning cold air advection. Highs only in the 50s are probable despite a return to sunshine. By Saturday night, ideal radiative cooling conditions will be in place. Temperatures in the 30s are very likely with widespread frost. Northeastern portions of our CWA may even dip into the low 30s or upper 20s. We have issued a Freeze Watch for these northeastern areas Saturday night into Sunday morning. Depending on how the surface high sets up, the Freeze Watch may need to be expanded in further updates. Similar conditions are likely Sunday night with areas of frost likely, especially in rural locations. NEXT WEEK Ensemble guidance is in good agreement showing surface high pressure remaining in place through at least mid next week...possibly even the entire week. Aloft, troughing is replaced by ridging. These two factors point towards a warming trend through next week. The warming should be gradual, as the advective component is not there. Highs rebound into the 70s which is a far cry from the near 90 readings we saw a few days ago. && .AVIATION (00Z TAF Issuance)... Issued at 524 PM EDT Fri Oct 16 2026 Impacts: - MVFR ceilings through tonight. - Wind gusts 20 to 30 knots through 04Z. - Rain showers possible this evening with minimal VIS impacts. Discussion: GOES19 imagery shows abundant cold air advection strato CU streaming across Indiana. Radar showing some rain showers within the cyclonic flow streaming toward IND and BMG. A moderate pressure gradient across the area was continuing to allow gusts to 20-25 knts. As daytime heating is lost this evening and the cyclonic flow lessens, winds will slowly subside and clouds should begin to show some breaks, as seen on upstream on GOES19 over NRN IL and WI. Thus have included some VCSH for the first few hours to account for the approaching showers. Overnight skies will be trended to VFR as strato cu is expected to dissipate as high pressure arrives from the west. Forecast soundings on Saturday continue to show a dry column as the high pressure system arrives, leading to VFR conditions and lighter winds. && .IND WATCHES/WARNINGS/ADVISORIES... Freeze Watch from late Saturday night through Sunday morning for INZ030-031-037>042-048-049-056-057-065. && $$ UPDATE...AGM AVIATION...Puma DISCUSSION...Eckhoff  973 FXUS61 KILN 170210 AFDILN Area Forecast Discussion National Weather Service Wilmington OH 1010 PM EDT Fri Oct 16 2026 .WHAT HAS CHANGED... Freeze Watch issued for Saturday night. && .KEY MESSAGES... 1) Occasional showers and brisk conditions will continue into tonight. 2) High pressure will build into the region through the weekend, bringing drier conditions and below normal temperatures. Widespread frost is likely Saturday night into Sunday morning. Temperatures will slowly moderate into midweek while conditions remain dry. && .DISCUSSION... Key Message 1) Post frontal precipitation and brisk conditions will persist across the area through this afternoon. Some wrap around shower activity may linger into tonight as a secondary cold front pivots through the area. In continued low level CAA, temperatures will drop into the mid 30s to lower 40s overnight, but clouds and winds will help prevent frost formation. Key Message 2) Surface high pressure will build into our area Saturday into Saturday night before beginning to shift off to the east on Sunday. This will bring dry and continued cold conditions. With the surface high centered over Ohio by early Sunday morning, expect good radiational cooling for Saturday night, with clear skies and light winds. Have undercut temps somewhat and will generally go with lows in the upper 20s to lower 30s, with cooler readings possible in the more sheltered areas. Have issued a Freeze Watch for our entire area for Saturday night into Sunday morning. Below normal temperatures will continue on Sunday with highs in the upper 50s to lower 60s. We will then gradually moderate through the rest of next week as the surface high shifts slowly east. && .AVIATION /00Z SATURDAY THROUGH WEDNESDAY/... Sharp mid level trof to pivot southeast thru the Ohio Valley with an associated surface trof dropping south of the Ohio River overnight. This will lead to scattered showers thru 06Z and then pcpn will taper off across most of the area. Can not rule out some additional showers overnight across the central Ohio TAF sites but coverage of these additional showers are too low to mention in the forecast at this time. Expect MVFR cigs to continue through the night in the wake of the TROF. Gusty west to northwest winds of 15 to 25 knots will prevail into this evening before becoming more northerly tonight as the TROF moves through. High pressure and a drier airmass will build into the region on Saturday with VFR conditions thru the afternoon. OUTLOOK...No significant weather expected. && .ILN WATCHES/WARNINGS/ADVISORIES... OH...Freeze Watch from late Saturday night through Sunday morning for OHZ026-034-035-042>046-051>056-060>065-070>074-077>082-088. KY...Freeze Watch from late Saturday night through Sunday morning for KYZ089>100. IN...Freeze Watch from late Saturday night through Sunday morning for INZ050-058-059-066-073>075-080. && $$ DISCUSSION...JGL AVIATION...AR  273 FXUS63 KFSD 170214 AFDFSD Area Forecast Discussion National Weather Service Sioux Falls SD 914 PM CDT Fri Oct 16 2026 .KEY MESSAGES... - Widespread frost continues to be expected tonight into early Saturday morning as temperatures fall into the lower to mid 30s. A Frost Advisory remains in place for central and south- central South Dakota, with a Freeze Warning elsewhere. Both headlines remain in effect from midnight to 9 AM. - Breezy conditions are expected tomorrow with gusts of 25-35 mph expected, locally higher over the Buffalo Ridge. These breezy winds coupled with drier air could lead to marginally elevated fire weather concerns in the afternoon. - Mainly dry conditions and warmer temperatures return this weekend into early next week with highs back above normal. && .UPDATE... Issued at 910 PM CDT Fri Oct 16 2026 A surface ridge continues to push through the area this evening. Its trajectory remains on track as a few locations west of the James River and across south central South Dakota are showing light southerly winds. This is also resulting in well behaved temperatures that continue to fall in line with expectations. Thus, still expecting temperatures to fall to the low to mid 30s, to even upper 20s in a few locations. The coldest temperatures continue to look to occur over parts of northwest Iowa where winds will go southerly the latest. As such, have kept all headlines in place. Still looking at temperatures to warm above freezing by the time the headlines expire at 9 AM. Winds remain on track to strengthen through the morning hours tomorrow, as low level pressure gradients continue to tighten. Southwest gusts up to 25 to 35 mph remain expected for the afternoon timeframe. Isolated higher gusts up to about 45 mph remain on the table as well along the Buffalo Ridge. Looks like any chance for these stronger wind gusts will come during the morning hours, right as mixing begins to deepen. These isolated stronger gusts will be short lived though as 925mb winds will be weakening a bit for the afternoon hours. Temperatures remain on track to warm to 50s and 60s, warmest along and west of I-29. These temperatures along with dew points remaining in the 30s will result in humidity values down to about 30-50%, lowest across south central South Dakota. The breezy winds, warm temperatures, and lower humidity will result in marginally elevated fire danger. While the highest potential fire danger will come across south central South Dakota, this area looks to be slightly offset from the strongest wind gusts. Will monitor the potential for fire danger in this area but think that locally higher fire danger is not as likely due to continued warm advection aloft, preventing deeper mixing from being achieved. Any fire danger will come to an end by sunset as temperatures cool and humidity increases. Sunday continues to look to be a pleasant day with highs remaining in the 60s but winds will be weaker, with gusts only reaching up to about 25 mph. && .DISCUSSION... Issued at 225 PM CDT Fri Oct 16 2026 The last of the clouds will continue to diminish over northwest Iowa and southwest Minnesota over the hour or two, leading to plenty of sunshine across the area! This sunshine should allow most areas to reach the lower 50s for highs, and decreasingly breezy winds will make for a cool, but fairly pleasant fall evening. Winds will be decreasing due to a surface high pressure system moving across the region. These lighter winds coupled with clear skies will mean temperatures will drop rather quickly after the sun sets. By the late night hours though, the high pressure system will quickly slide eastward and allow for the return of southeasterly winds to the area. This should halt the faster cooling and allow for areas especially over south- central South Dakota to remain above freezing, though still remain cold enough for frost. Thus, a frost advisory will be in effect for these areas tonight. Farther east, do think the slight uptick in southeasterly winds will not make it in time to prevent these areas from dropping to 32 degrees or lower. Generally speaking, the farther east you go across the area tonight, the longer it will take for the slightly elevated winds to arrive and thus the colder you'll get. Though there is still some lingering uncertainty on the westward extent of the freezing temperatures, current thoughts are that clear skies, light winds, and dry air during the early overnight will lead to these areas dropping to freezing by daybreak. All that said, frost is expected across the entire area overnight. Southeasterly winds will continue to increase heading into the day tomorrow as the high pressure system slides east and a low pressure system develops off the northern Rockies. Winds won't be as strong as what we've seen this morning and this past night, but expect most areas to see gusts in the 25-35 mph range during the day on Saturday. A few gusts to 45 mph will be possible over the higher elevations of the Buffalo Ridge, but this is not expected to be widespread enough to warrant wind headlines at this time, though trends will be monitor. Another thing to monitor will be locally elevated fire weather conditions Saturday afternoon. Warmer temperatures are expected especially over south-central South Dakota, with highs in the 60s and possibly near 70. This combined with dew points well down into the 30s will lead to relative humidity values just below 30% in south-central South Dakota. Elsewhere, relative humidity values will be around 30-50% Saturday afternoon. This could all result in locally elevated fire weather concerns mainly in cured grasses and cropland. Ridging aloft builds in through the weekend, allowing for a seasonal weather pattern to return that will also continue into early next week. Sunday looks to be the better weekend day for outdoor activities with diminishing winds, sunny skies, and highs in the middle 60s. A weak upper wave will ride into the central Plains into the upper Midwest Tuesday into Tuesday night, though probabilities of measurable rainfall with this system is low (<20%) and focused near and east of I-29 according to latest LREF probabilities. After this weak system passes through, ridging builds back in aloft, and this combined with continued southerly flow will lead to even warmer temperatures by the middle of the week. Highs by Wednesday and Thursday will potentially climb into the 70s across parts of the area. The NBM is a bit more aggressive than other ensembles, though is only warmer by a few degrees comparatively speaking. Either way, forecast temperatures will likely get refined as mid week approaches as more smaller scale details come into better focus. Looking out to the end of next week, the weather pattern may turn a bit more active as guidance indicates a western trough potentially ejecting into the area, though the timing of this is where models really diverge. The broad 20-40% PoPs as highlighted by the NBM next Friday is largely in line with 16.12Z LREF, though details with this system will once again become more clear as we approach the end of next week. && .AVIATION /00Z TAFS THROUGH 00Z SUNDAY/... Issued at 635 PM CDT Fri Oct 16 2026 VFR conditions are expected for the TAF period. Light northwest winds begin the period but will go light and variable over the next hour or two. However, winds will back to out of the south through the overnight hours and begin to strengthen again. Winds will veer to out of the southwest by Saturday morning and continue to strengthen. Gusts up to 20-35 knots are expected for tomorrow afternoon. The strongest gusts will occur along the Buffalo Ridge in southwest Minnesota and across south central South Dakota. The breezy southwest winds will finish out the TAF period. && .FSD WATCHES/WARNINGS/ADVISORIES... SD...Freeze Warning until 9 AM CDT Saturday for SDZ039-040-054>056- 060>062-065>071. Frost Advisory until 9 AM CDT Saturday for SDZ038-050-052-053- 057>059-063-064. MN...Freeze Warning until 9 AM CDT Saturday for MNZ071-072-080-081- 089-090-097-098. IA...Freeze Warning until 9 AM CDT Saturday for IAZ001>003-012>014- 020>022-031-032. NE...Freeze Warning until 9 AM CDT Saturday for NEZ013-014. && $$ UPDATE...Meyers DISCUSSION...Samet AVIATION...Meyers