Forecast Discussions mentioning any of "ACARS" "MDCRS" "AIRCRAFT" "TAMDAR" "AMDAR" "WVSS" received at GSD on 04/29/22

Area Forecast Discussion
National Weather Service Lincoln IL
841 PM CDT Thu Apr 28 2022 .SYNOPSIS... Issued at 300 PM CDT Thu Apr 28 2022 Periods of showers and thunderstorms are expected through the first half of the weekend, with the most widespread chances from late Friday night through Saturday evening. Some of the storms may be severe Saturday afternoon and evening. Expect overnight temperatures to remain mild, mainly in the 50s. While Friday`s highs will only be in the lower 60s, expect widespread 70s to start the weekend. && .UPDATE... Issued at 840 PM CDT Thu Apr 28 2022 Weak frontal zone remains stalled over the area. Subtle WAA continues to produce a few areas of light showers this evening, though coverage has diminished considerably over the last few hours. Cloud bases remain around 6-8 kft, so any precip that does reach the surface should stay light. Made some adjustments to PoPs through midday Friday, as latest CAMs seem are a bit slower bringing shower/storm activity into the CWA. && .SHORT TERM...(This evening through Friday) ISSUED AT 300 PM CDT Thu Apr 28 2022 Showers have been increasing across the forecast area this afternoon, despite the drier low levels shown on 18Z AMDAR sounding out of St. Louis and by ceilings generally 8,000 feet or higher across central Illinois. MRMS show an area of rainfall of a couple tenths from near Galesburg east to Marshall County. Back edge of the rain is seen on radar mosaics from near the Quad Cities to Kansas City. High-res guidance have not had the greatest handle on this activity, with perhaps the NAM Nest coming closest, and that one would suggest a general diminishment in the evening. However, the CAM`s are in better agreement of a cluster of showers/storms developing after midnight in the central Plains and moving toward the mid-Mississippi Valley. Highest rain chances appear to be during the mid morning into early afternoon on Friday. .LONG TERM...(Friday night through Thursday) ISSUED AT 300 PM CDT Thu Apr 28 2022 Initial focus in this section remains with the severe weather potential for Saturday. Main concern is with the amount of cloud debris that may be left over from the morning activity, which the CAM`s have located roughly near I-55 around sunrise. Assuming we can get enough thinning of the clouds, NAM/GFS both advertise CAPE`s around 1500 J/kg in the afternoon and 40-50 knots of bulk shear advancing east across the state, which should be enough to get some scattered strong/severe storms. Models are coming into better agreement with the track of the strong upper low over the central Plains, lifting northeast into northern Wisconsin by midday Sunday. The bulk of the rain should be out of our area by late Saturday evening, but a few wraparound showers can`t be ruled out on Sunday across the northern CWA. The next storm system also has some good agreement among the models, with widespread rain chances Monday night and Tuesday. After that, model divergence takes over with placement of the next upper low over the central U.S. The GFS is much faster than the international models and have a storm system over the mid- Mississippi Valley by Wednesday evening, while the international models still have it well back in the Plains with a farther south track. Besides the precipitation discrepancies, the GFS would suggest another cool shot of air late next week. && .AVIATION...(For the 00Z TAFS through 00Z Friday evening) Issued at 614 PM CDT Thu Apr 28 2022 SE winds prevail through the period, with gusts of 20-25 kts during the day Friday. A band of showers is expected to track from southwest to northeast across the area tomorrow, reaching KSPI late morning. A few embedded t-storms are possible, though how far north t-storms occur is uncertain, so refrained from including VCTS at KPIA/KBMI/KCMI for now. Ceilings should drop to near or just below 3000 feet in the precip. && .ILX WATCHES/WARNINGS/ADVISORIES... NONE. && $$ UPDATE...Erwin SYNOPSIS...Geelhart SHORT TERM...Geelhart LONG TERM...Geelhart AVIATION...Erwin