Area Forecast Discussion
Issued by NWS Topeka, KS
Issued by NWS Topeka, KS
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943 FXUS63 KTOP 060548 AFDTOP Area Forecast Discussion National Weather Service Topeka KS 1248 AM CDT Mon May 6 2024 .KEY MESSAGES... -Dense fog tonight, generally south of I-70. -A dynamic system is still on track to bring severe weather back to the area tomorrow afternoon and evening. Very large hail, strong winds and tornadoes will all be possible. -Drier weather is then expected mid and late week. && .UPDATE... Issued at 1242 AM CDT Mon May 6 2024 A Dense Fog Advisory has been issued for areas along I-35 and south for tonight into early Monday morning. Visibility is already falling to around one mile across portions of east central Kansas. Some short-term models suggest this fog will spread further north by the early morning, so further expansion of the Dense Fog Advisory may be needed. && .DISCUSSION... Issued at 254 PM CDT Sun May 5 2024 This afternoon, there are two systems of importance to note - a shortwave trough over Arkansas, slowly moving northeast within the mid-level flow, and a stronger system over the western CONUS, evident on water vapor imagery by a tight cyclonic circulation centered near the OR/ID stateline. Light rain associated with the first system has slowly moved northward with time today. Light QPF is forecast across east-central KS into mid-afternoon before rain tapers off and moves east of the area. Cloud cover and rain today are keeping temperatures in the upper 50s and low 60s. Stratus will remain in place tonight with models also showing some signal for fog development, mainly were rain fell today. If winds are able to go light (less than 5 mph), fog will become more likely. For now, however, the extent of fog is expected to be limited. The western CONUS system still looks concerning regarding the severe weather potential in central and eastern KS tomorrow. Surface low pressure will deepen and move out over the northern high plains late morning as the mid-level negative tilt trough axis approaches that region. Instability may be slow to increase in eastern KS through the midday hours, given lingering low cloud cover. However, strong low level moisture transport into the area will increase buoyancy while mid level lapse rates steepen, resulting in between 1500-2500 J/kg of MLCAPE ahead of the dryline tomorrow afternoon. Expected shear parameters remain impressive, with forecast sounding analysis showing near 250 m2/s2 of effective inflow layer SRH and around 50 kts of effective bulk shear. CAMs are in good agreement with development occurring along the cold front/dryline in central KS early to mid afternoon with storms forming into a line or broken line segment and quickly advancing eastward into the evening hours. If this exact scenario plays out, very large hail and tornadoes will be the main concerns initially, with an increasing wind and QLCS tornado threat as the evening progresses. Evolution of storm mode remains somewhat in question, but the bottom line is that all modes of severe weather could again occur as our active spring season continues tomorrow. Storms moves east of the area Monday night, leaving dry weather in the forecast for Tuesday. However, another shortwave looks to develop and move around the main system that will then be sitting north of the area Tuesday night and early Wednesday. That could generate a few showers or storms early Wednesday. A severe weather threat could develop ahead of that secondary boundary, but will likely be southeast of the area, mainly in the Ozarks. A stretch of dry and seasonable weather is then expected through the remainder of the workweek. && .AVIATION /06Z TAFS THROUGH 06Z TUESDAY/... Issued at 1242 AM CDT Mon May 6 2024 IFR conditions tonight, becoming MVFR by late morning. Low stratus, fog and drizzle are all likely tonight as warm, moist advection from the south overspreads the area. There is some uncertainty as to how low and thick cloud cover will remain through the day tomorrow, but MVFR conditions are currently favored. A line of thunderstorms is still favored to move through after 00z Tuesday. && .TOP WATCHES/WARNINGS/ADVISORIES... Dense Fog Advisory from 4 AM to 9 AM CDT this morning for KSZ054-KSZ055-KSZ056-KSZ058-KSZ059. && $$ UPDATE...Jones DISCUSSION...Teefey AVIATION...Jones