346 FXUS63 KTOP 051909 AFDTOPArea Forecast Discussion National Weather Service Topeka KS 209 PM CDT Sun Oct 5 2025
.KEY MESSAGES...
- Isolated strong to severe storms are expected to form in vicinity of a cold front early this evening. Gusty winds up to 60 mph and small hail are the main hazards.
- The cold front and associated scattered showers pass through northeast Kansas on Monday, cooling highs down to the 60s and 70s through Wednesday.
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.DISCUSSION... Issued at 209 PM CDT Sun Oct 5 2025
Longwave troughing influences much of the western and central CONUS this afternoon, as southwesterly flow streams through the central plains. The cold front is oriented from northwest Kansas to south central NE where some clouds have cleared. The front is progged to progress southeast this evening, showers and scattered storms after 6 PM. Just ahead of the boundary, forecast soundings in north central Kansas are consistent with increasing low level lapse rates amid the higher cloud bases. Forecast CAPE values increase to near 1000 J/KG with decent effective shear values of 30-40 kts. The inverted v soundings lend to highest severe probabilities of wind gusts up to 60 mph with a lesser threat for small hail and localized heavy rainfall. PWAT values this evening into the overnight increase to near 1.5 inches in north central Kansas as a strengthening LLJ develops additional showers and storms. Some training of storms through Tuesday morning may result in localized heavy rainfall with consensus guidance showing total QPF amounts from 0.75 to 2 inches along and west of a line from Minneapolis to Marysville. A few outliers are showing locally higher rainfall totals and will be highly dependent upon the presence of an embedded vort max aloft bringing a more organized round of heavier showers and storms into north central areas overnight. Overall forecast rainfall amounts have increased, especially north of I-70 and west of highway 75 with 50-70% probability of at least 1 inch or higher through Tuesday morning.
The cool 1030mb sfc ridge settles into the area Tuesday and Wednesday as winds weaken below 10 mph and forecast highs are 15 to 20 degrees cooler than the weekend {middle 60s to low 70s). There remains a low chance for showers and storms Thursday and Thursday night as a progressive shortwave trough crosses the northern plains. Ensembles differ on the depth of the wave this far south so confidence in measurable precip is low. Heights build once again towards the end of the week as southerly flow warms highs back to the 80s.
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.AVIATION /18Z TAFS THROUGH 18Z MONDAY/... Issued at 1207 PM CDT Sun Oct 5 2025
VFR at terminals to start forecast period with focus on incoming fropa and widespread showers from the northwest. Gusty south winds this afternoon subside to just below 10 kts aft 00z before the prefrontal boundary veers winds to the northeast at 5-8 kts in the 05-08Z time frame. TSRA is more probable at KMHK with lesser instability for just showers at KTOP/KFOE. Exact timing of the main front is variable among guidance (from late morning to mid afternoon) with the arrival of IFR stratus and scattered showers.
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.TOP WATCHES/WARNINGS/ADVISORIES... None.
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DISCUSSION...Prieto AVIATION...Prieto
NWS TOP Office Area Forecast Discussion