Sunrise 6:32 AM   Sunset 8:15 PM Moonrise 9:28 PM   Moonset 6:10 AM

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FXUS63 KTOP 250532 AFDTOP

Area Forecast Discussion National Weather Service Topeka KS 1232 AM CDT Thu Apr 25 2024

KEY MESSAGES

- Showers and storms becoming likely late tonight into Thursday with a small risk for severe storms.

- Severe thunderstorm potential returns Thursday night, Friday afternoon, then Saturday afternoon and night with more impactful storms likely

DISCUSSION
Issued at 249 PM CDT Wed Apr 24 2024

Weak mid-level isentropic lift has resulted in considerable high- level cloud today but little precip making for a pleasant spring day in dry air and light winds. Conditions get more concerning through the night and into at least mid-weekend. The overall forecast has not changed much from previous forecasts.

Models are in fairly good agreement with the elevated mixed layer over moistening lower levels being weaker than expected.
Precipitation is likely to increase from more isolated regime to waves of showers and storms late tonight into Thursday morning with 850 mb moisture convergence focusing not far to the west late tonight. CAPE based around 800 mb increases to near 1000 J/kg with moderate effective shear supporting at least a small large hail threat with the stronger updrafts that can form. This activity would likely exit around midday Thursday leaving behind a wet and cool boundary layer covered in stratus. Vigorous thunderstorms are still expected to form in the late afternoon in western Kansas and move northeast, but should diminish to a hail threat as they approach in the late evening and overnight hours. There will be some potential for precip to form locally but this could be more showery in nature with indications of the EML increasing.

The dryline's eastward progression through the area Friday continues to be a focus. Convergence along it remains meager and stratus may remain rather stubborn ahead of it limiting instability, though there are better indications of upper support via weak height falls.
Upper level winds are not very strong keeping shear a bit more limited but the scenario for at least isolated storm development in eastern Kansas remains in play with surface-based supercell threats.
Surface winds still should at least approach Advisory levels for sustained and gust speeds but guidance means have backed off a bit on the extreme mixing potential.

Deep-layer shear increases ahead of the second upper wave late Saturday. Stratus may again be present in eastern areas into the afternoon but the setup still supports severe thunderstorm and training storm potential in the late afternoon and night. The wave lingers into Sunday but remaining instability should be much reduced.

Broad upper troughing with weak surface high pressure gets replaced with near-zonal flow with perhaps a weak wave around Wednesday.

AVIATION /06Z TAFS THROUGH 06Z FRIDAY/
Issued at 1229 AM CDT Thu Apr 25 2024

VFR to start TAF period as scattered SHRA gradually becomes more widespread as moisture increases from the south. Cigs are expected to quickly fall to IFR as scattered TSRA develops from 11Z-14Z, moving southeast through early afternoon. A few short term models try to lift cloud bases to MVFR in the late afternoon, however with the continued warm and moist advection, I am leaning towards IFR stratus remaining through the remainder of the period. There may also be additional showers that develop aft 00Z.

TOP WATCHES/WARNINGS/ADVISORIES
None.

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