771 FXUS63 KTOP 211130 AFDTOPArea Forecast Discussion National Weather Service Topeka KS 630 AM CDT Sun Sep 21 2025
.KEY MESSAGES...
-The forecast contains several chances for rain/storms from today through Wednesday.
-A few strong storms could occur this afternoon in far eastern KS.
-Temperatures will be fairly seasonal through the forecast period.
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.DISCUSSION... Issued at 307 AM CDT Sun Sep 21 2025
Prior to sunrise this morning, radar was showing scattered rain showers in central KS where some isentropic ascent was occurring on the nose of a nocturnal LLJ. Am expecting to see those showers possibly expand in coverage as they move eastward into the forecast area. Some lightning strikes will be possible with some instability present, however, shear is very weak. Thus, no severe weather is expected through the morning hours. Some additional development could occur midday as an H5 shortwave trough axis rounds the base of low pressure over the Upper Midwest, enhancing lift over the area. A few stronger storms could occur in far eastern KS as instability and shear increase this afternoon ahead of the wave.
A brief break in precipitation chances is forecast Monday as a low amplitude mid-level ridge builds in between today`s mid-level wave and another that will quickly dig southward out of the Pacific Northwest region. As that next system evolves into a closed low over the Rocky Mountains, surface low pressure will move through the Central Plains and rain chances will increase Monday night and Tuesday morning. Tuesday appears to bring the best potential for widespread rainfall to the area. Have maintained POPs of 60-80% through the afternoon. Rainfall totals are somewhat uncertain, given some model variability. The NBM has a 40% chance for at least one inch in and around Topeka, while LREF has closer to a 20% chance, higher chances south of I-35.
Into midweek, models merge Tuesday`s closed low pressure system with another lingering system over the Great Lakes region. The merged low looks to slowly rotate around portions of the Midwest for a few days. Each model has a slightly different idea of where it will be centered, but either way, some lingering showers, cloud cover and cool temperatures will likely be the result for the second half of the upcoming workweek.
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.AVIATION /12Z TAFS THROUGH 12Z MONDAY/... Issued at 628 AM CDT Sun Sep 21 2025
VFR is forecast for the 12Z TAF period. Rain has moved over KMHK and will expand eastward to the Topeka airports this morning. Rain showers are expected to persist for several hours, after which a few storms could develop near KTOP/KFOE this afternoon. Otherwise, winds remain light and turn to a southerly direction.
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.TOP WATCHES/WARNINGS/ADVISORIES... Dense Fog Advisory until 9 AM CDT this morning for KSZ012.
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DISCUSSION...Teefey AVIATION...Teefey
NWS TOP Office Area Forecast Discussion