Area Forecast Discussion
Issued by NWS Topeka, KS
Issued by NWS Topeka, KS
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782 FXUS63 KTOP 161724 AFDTOP Area Forecast Discussion National Weather Service Topeka KS 1224 PM CDT Tue Jul 16 2024 .KEY MESSAGES... - Low chances (15-25%) for storms this evening and overnight. If storms impact the area, they could produce gusty winds. - Heat indices from 100 to 103 are expected this afternoon along and south of I-35. - Below normal temperatures settle in Wednesday onward, followed by precip chances returning this weekend. && .DISCUSSION... Issued at 308 AM CDT Tue Jul 16 2024 Series of embedded perturbations noted withing the quasi-westerly flow aloft across the central plains region this morning. The strongest impulse over western Kansas has developed a cluster of convection while more scattered activity is developing upstream into north central Kansas, in proximity to the 850 mb front where isentropic ascent along the 310-320K surfaces is gradually increasing through sunrise. Despite variances in short term guidance on the evolution of this activity, models and observations are consistent in ample MUCAPE and effective shear values up to 35 kts to sustain activity as the shortwave trough slides eastward into eastern Kansas later today. The depth of the wave is not particularly strong so there is some uncertainty on the coverage of precipitation during the morning period. Nevertheless, it seems prudent to maintain low chance pops as activity should become more isolated in the afternoon. Redevelopment of convection is possible along the h85 boundary by late afternoon as SFC cape surges above 4000 J/KG with little to no inhibition. Effective shear is fairly weak and lapse rates are not too impressive so would believe coverage to be isolated at best. Updrafts may be capable of strong wind gusts up to 50 mph. Additionally, another shortwave trough is progged to slide southeast this evening, developing a cluster of storms across southern NE. These storms may impact north central areas this evening, producing severe wind gusts and hail. Activity gradually weakens overnight while another round of showers and storms focuses across southern Kansas and northern Kansas. In collaboration with our southern neighbors, opted to keep slight pops this evening, however latest guidance would support better forcing near the front being south of the CWA with much of the area being dry overnight. The cooler airmass arrives Wednesday morning as gusty northeast winds in the afternoon bring high temperatures down to the lower and middle 80s. Dry, cool, and mostly sunny conditions reign through Friday. Abnormally cool sfc high pressure continues to spread southwestward this weekend as a southward moving upper low increases cloud cover, storm chances, and reinforcing cooler air with highs around 80 and lows in the low 60s through early next week. Timing of the upper trough is somewhat similar between GFS and EC ensembles of highest pops on Saturday evening however, precip chances may linger into next week as ridging over the southeast CONUS may slow the progression of the upper low away from the region. && .AVIATION /18Z TAFS THROUGH 18Z WEDNESDAY/... Issued at 1224 PM CDT Tue Jul 16 2024 VFR conditions expected. There is some signal for low stratus to build in after 10z Wednesday, but confidence in this scenario is too low for inclusion. Winds remain light from the northeast through the period. && .TOP WATCHES/WARNINGS/ADVISORIES... None. && $$ DISCUSSION...Prieto AVIATION...Flanagan