Area Forecast Discussion
Issued by NWS Paducah, KY
Issued by NWS Paducah, KY
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598 FXUS63 KPAH 061758 AFDPAH Area Forecast Discussion National Weather Service Paducah KY 1258 PM CDT Mon May 6 2024 .KEY MESSAGES... - Scattered showers and storms will generally increase in coverage and intensity potential by mid week. A severe storm outbreak is possible both Tuesday and Wednesday. - Breezy south winds will pick up in similar fashion, offering 30-35 mph gust potential Tuesday-Wednesday. - A warm and relatively muggy air mass holds through mid week before a cool off with lower humidity returns spring like temperatures and dew points as we finish out the week and head into next weekend. && .DISCUSSION... Issued at 215 AM CDT Mon May 6 2024 A weakening open wave with its reflected surface inverted trof slides across the area today, over an airmass of lower 60s dew points that soup into the mid 60s over the course of the day as temps push thru the 70s. The eastward tracking low sees the LLJ shift eastward as well, which keeps highest pops there, perhaps AOA NBM`s depiction, while in the far west, we`ll see a west- to-east diminishing trend after early this morning, ie AOB the NBM depicting. This has been collaborated and the forecast adjusted accordingly. Shear and lapse rates are lacking so (outside an isolated pulse storm) most of these are general risk, mainly locally heavy downpour, showers/storms expected today. A (relative) pause in pops is still expected thru the first half of the night as a teleconnected ridge moves across the area in the wake of the departed open wave. However, by late tonight, the first wave of positive vorticity advection from the parent big storm system over the High Plains moves in from the north and west on the nose of increasing upper level winds. We see the shear and lapse rates begin to respond accordingly, and a burgeoning chance of storms is incoming by 12Z Tuesday. A slight risk of severe is still forecast for the area as these dynamical features translate across the FA under a warm sectoring environ. The noisy early day convection upstream may retard later day diurnal/instability convective firing, as better focus areas shift eastward. We like the broad-brushed SLGT for now but conditional within it is understood a better chance north and west early, transitioning to a better chance north and east by late in the day. We could see these areas (whether within or just beyond our CWA bounds) as the best focused areas for stronger storm activity. Another relative pause in pops occurs late Tuesday night as this energy shifts eastward/beyond our effective reach. Then the focus turns to another best time chance for strong-severe storms...still looking like Wednesday afternoon-evening. Warm sector convection may begin firing a little earlier, by mid morning, while the late day convective outbreak may extend into or thru the night. Bulk shear increases to 50+ kts and lapse rates balloon upward to 8C, so this would appear to offer our best/strongest dynamical potential for a severe outbreak, not discounting the Tuesday evolution. We can see the Wednesday slight risk being upgraded with time, but it`s still a pretty broadly painted areal depiction for pinpointing exactly where...stay tuned on that. All modes severe cannot be ruled out either Tuesday or Wednesday, and heavy rainfall potential capable of localized flooding heightens each day as well, also peaking Wednesday-Wednesday night. In addition, the non thunderstorm gradient winds spike Tuesday-Wednesday as well, with gust potential just shy of Advisory criteria. Beginning Thursday, we`ll see the mean trof make its passage and a transition toward a much cooler/drier spring-like air mass finishes out the week and extends into the weekend...with highs generally in the 70s and dew points dropping thru the 50s to the 40s. && .AVIATION /18Z TAFS THROUGH 18Z TUESDAY/... Issued at 1251 PM CDT Mon May 6 2024 Disturbance will lead to isolated-scattered convection developing this afternoon, mainly focused across the east half of the region. Lingering MVFR cigs (and even some IFR) are expected to gradually lift to VFR levels by late afternoon. A general lull in activity is expected this evening and early overnight. After 09z a line of convection may spread eastward across the area. It should be in a weakening phase through early-mid morning. MVFR conditions are expected to accompany this. Southerly winds will increase tomorrow morning with some gusts of 20-25 kts anticipated. && .PAH WATCHES/WARNINGS/ADVISORIES... IL...None. MO...None. IN...None. KY...None. && $$ DISCUSSION...07 AVIATION...SP