Area Forecast Discussion
Issued by NWS Topeka, KS
Issued by NWS Topeka, KS
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092 FXUS63 KTOP 031746 AFDTOP Area Forecast Discussion National Weather Service Topeka KS 1246 PM CDT Wed Jul 3 2024 .KEY MESSAGES... -More wet weather is expected from today through Independence Day. -A few severe storms could impact holiday festivities in far eastern KS during the afternoon/evening tomorrow. -A continued active pattern will bring storms back to the region during the upcoming weekend. && .DISCUSSION... Issued at 417 AM CDT Wed Jul 3 2024 This morning, the surface boundary that moved through the area yesterday has slowed it`s southward progression and is located from east-central into southeast KS. The 850mb front is displaced slightly further to the north. A surface ridge has expanded over Nebraska, with an associated drier air mass nudging into north- central KS. Some radiational fog is developing where skies have cleared, so have a mention of mainly patchy fog in the forecast early this morning. In the meantime, thunderstorms were increasing in coverage at 08Z in southwest KS where WAA was occurring within a zone of southwesterly flow. That batch of precipitation will move toward the forecast area today. Thus, have POPs increasing through midday. Instability will be limited north of the aforementioned sfc/850 fronts, so mainly rain with some embedded thunder is expected. The best chance for thunder will be in those locations near central and southeast KS. Late this afternoon, CAMs are in good agreement with scattered convection developing across the High Plains as a shortwave trough traverses that region. Those storms are expected to weaken as they move eastward, with MUCAPE likely remaining less than 1000 J/kg for much of the area. A few damaging wind gusts could occur in central KS, but the overall severe threat looks fairly limited tonight otherwise. Focus then turns to the holiday forecast. Lingering showers/storms from tonight will end from west to east Thursday morning. Throughout the day, a mid-level trough will deepen over the northern plains states. Another surface boundary will set up over the area as the trough moves east, deeper into the Midwest. Instability will build over eastern KS ahead of the front, which is expected to be near a line extending from Hiawatha to Topeka to Emporia around 21Z. Large scale forcing generally looks weak, but convergence along the boundary could allow (30-50% chc) for scattered storms to develop in eastern KS during the afternoon/early evening. If storms develop, damaging wind gusts and heavy rainfall will be the main concerns. Storms will move east during the evening hours, hopefully in time for firework related celebrations. A surface ridge then builds into the area on Friday, keeping conditions dry and temps below average. The next in a series of mid-level troughs looks to enter the Midwest late Saturday. POPs increase (to around 40-50% chcs) from west to east across the CWA late Saturday and Sunday. Rain clears and temps begin to increase again early next week, back to around 90 degrees by Tuesday. && .AVIATION /18Z TAFS THROUGH 18Z THURSDAY/... Issued at 1245 PM CDT Wed Jul 3 2024 Low clouds at TOP/FOE have scattered with mid/high clouds remaining over all sites. Have removed mention of VCTS for this afternoon, as scattered showers across the entire state have had very little lightning observed with them and with weak instability, would expect any TS to be too isolated to mention in TAFs for the next several hours. Better chances for convection are with storms coming in from western/central KS overnight, so have added VCTS associated with that. The signal for heaviest rainfall is well south of terminals, so any vis reductions should be brief if any. Restrictions expected to come with MVFR cigs during the morning following the storms. Some guidance shows IFR may be possible during that time, but confidence isn`t high enough to go that low with cigs just yet. && .TOP WATCHES/WARNINGS/ADVISORIES... None. && $$ DISCUSSION...Teefey AVIATION...Picha