612 FXUS63 KTOP 241146 AFDTOP Area Forecast Discussion National Weather Service Topeka KS 646 AM CDT Sun Oct 24 2021 ...Update to aviation forecast discussion... .DISCUSSION... Issued at 320 AM CDT Sun Oct 24 2021 Today, early this morning an upper level trough was located across eastern CO. A surface low was located just northeast of DDC at 2 AM with a surface warm front extending east-southeast across south central and southeast KS. The combination of isentropic lift, the LLJ and DCVA provided enough ascent for elevated thunderstorms to develop across northeast and east central KS. Another batch of elevated storms have develop over ICT and to areas southeast of HUT. This area of thunderstorms will move northeast across the eastern half of the CWA during the morning hours. Some of the storms could be strong to marginally severe with the primary hazard being quarter size. Once the LLJ shifts east across MO and the PBL mixes deeper, the warm front should make a sudden jump northward ahead of the surface low that will track from northeast of DDC to Brown County by 18Z. The upper trough will move east across the state during the mid morning to early afternoon hours. A pre frontal trough will shift east across the CWA by the early afternoon hours proceeded by the surface cold front. The surface low will move east-northeast into southern IA during the late afternoon hours. Thunderstorms will redevelop this afternoon across west central MO, well east of the CWA. So after this morning elevated thunderstorms, the severe weather threat will shift east of the CWA during the afternoon hours. The highs across east central KS behind the surface trough and ahead of the the surface cold front will reach the lower to mid 70s during the early afternoon hours. As the front passes southeast, winds will shift from the west-southwest to the northwest and low-level CAA will cause temperatures to drop through the 60s during the mid and late afternoon hours. The surface front will move east across the western half of the CWA during the mid and late morning hours and highs will be in the lower to mid 60s this morning with temperatures holding steady or slowly falling into the mid 50s during the mid and late afternoon hours. Tonight, the upper trough axis will shift east into the mid MS River Valley and amplify. Northwest flow will develop across the Plains states. The skies will clear from northwest to southeast across the CWA. Winds will slowly diminishing through the night and temperatures across north central KS will drop into the upper 30s by sunrise. The northwest winds will continue at 5 to 10 MPH through the night, thus frost formation may not occur across north central KS. Monday through Tuesday, An amplified upper trough will move onshore across the western US, then move east across the central Rockies into the central and southern high Plains Tuesday afternoon. A down stream upper ridge will move east across the Plains on Monday, then shift east across the mid and lower MS river Valley by late Tuesday. A lee surface trough will deepen across the central and southern high plains on Tuesday. A surface ridge of high pressure will be centered over eastern KS on Monday and will drift east into MO Tuesday night. Highs on Monday will only reach the upper 50s to lower 60s with light northeast winds which will back to the east during the afternoon hours. Expect a warm up on Tuesday as the lee trough deepens and southerly winds and low-level WAA help high temperatures to reach the upper 60s to mid 70s. Tuesday night through Thursday, the upper trough will amplify into a closed low as it moves east across OK on Wednesday. At this time severe thunderstorms will develop across western OK into west central TX Tuesday evening and track east across OK and north TX. As the upper low amplifies across western OK, northeast KS will see the mid and upper flow become meridional and eastern KS may see a bit of training of elevated storms on the east side of the upper low, which will move east and provide some heavier rainfall late Tuesday night into Wednesday. The severe thunderstorms will remain well south across OK and TX. The low will be slow to move east into the lower MS River valley and a TROWAL may set up over eastern KS providing a steady rain Wednesday night into Thursday morning. Thursday afternoon the light rain will shift east into MO through the afternoon hours as the upper low tracks east into the lower MS River Valley. Given cloud cover and periods of rain and few elevated thunderstorms, high temperatures will only reach the 60s. Thursday night through Sunday, The amplified upper trough will move into the eastern US and this will keep the Plains under northwesterly flow aloft. Highs will only reach the lower to mid 60s on Thursday and Friday. We amy see a brief warm up into the mid 60s to around 70 on Saturday. An upper level trough will move east across the northern Plains and southern Canada Saturday night, and strong Low-level CAA will bring a stronger cold front southward across the CWA Sunday morning. Highs on Sunday may only reach the mid to upper 50s. We may see our first freeze Sunday night or Monday night. && .AVIATION...(For the 12Z TAFS through 12Z Monday morning) Issued at 639 AM CDT Sun Oct 24 2021 The main line of elevated thunderstorms have pushed east of the terminals but there may be vicinity of thunderstorms through the mid morning hours. A cold front will move through the terminals during the late morning and early afternoon hours. Behind the front will be MVFR stratus, that may scatter out during the evening hours. Surface winds look high enough that the low-level wind shear should be below 30 KTS. && .TOP WATCHES/WARNINGS/ADVISORIES... NONE. && $$ DISCUSSION...Gargan AVIATION...Gargan