Area Forecast Discussion
Issued by NWS Quad Cities, IA IL
Issued by NWS Quad Cities, IA IL
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272 FXUS63 KDVN 021727 AFDDVN Area Forecast Discussion National Weather Service Quad Cities IA IL 1227 PM CDT Sun Jun 2 2024 .KEY MESSAGES... - An active, summer-like pattern will be found through early week, with warm/muggy conditions and multiple rounds of showers and storms. Monday PM and Tuesday PM/night will be monitored for strong to severe storms. - Mainly dry mid week to late week with seasonal temperatures. && .Update... Issued at 1000 AM CDT Sun Jun 2 2024 We cleared out the dense fog advisory around 830 AM this morning as the fog had lifted in all areas except for northern valley sites. The stratus may continue to plaque our forecast through early afternoon in the wake of the fog event, and I`ll be looking at potentially lowering highs today...which might actually make it a more pleasant afternoon. && .SHORT TERM /THROUGH TONIGHT/... Issued at 325 AM CDT Sun Jun 2 2024 Surface to 850 hPa ridge is building in early this morning. The light to calm surface winds, low level moisture aided by recent rainfall, and clearing stratus has allowed fog to form near and especially west of the Mississippi River, which has become dense in areas. Further east into northwest Illinois, still hanging on to weak cyclonic flow with satellite and obs showing more in the way of stratus than fog. However, as the ridge builds in we could see more in the way of fog develop in these areas around daybreak should the stratus decrease. Little in the way of mixing for much of today and a little cirrus atop may allow the fog and/or stratus to hang around into the late morning. Following the lifting of the fog, a partly cloudy and seasonable conditions are on tap with highs in the upper 70s to lower 80s and moderate humidity. Late this afternoon into evening, we can`t rule out some spotty convection in portions of E Iowa and NE Missouri as remnant AM Central Plains activity and possible attendant MCV shifts east. This potential currently looks isolated (<20%) for mention given mid level ridging still largely in control. However, pending convective trends out west if a stronger MCV were to occur then will need keep an eye out for possibly needing low mentionable PoPs into our western service area. Better prospects for showers and some storms will occur overnight into Monday AM, with a veering nocturnal LLJ and attendant warm/ moist advection and elevated convergence coupled with lift from low amplitude shortwaves in zonal flow aloft. && .LONG TERM /MONDAY THROUGH SATURDAY/... Issued at 325 AM CDT Sun Jun 2 2024 A potential MCV tied to the early Monday convection could foster some potential for redevelopment of showers/storms by afternoon, especially in the south/east portions of the service area. Any Monday PM convection would need to be monitored for organized multicell clusters capable of strong gusty winds and small hail. This threat is conditional upon timing of the wave, and notable augmentation to the deep layer shear in the presence of moderate instability (MLCAPE progged around 1500+ j/kg). Otherwise, largely south/southwest low level flow/ warm advection will foster above normal warmth, which coupled with increasing humidity will make it feel very summer-like through early week. Toward mid to late next week the guidance continues to support a pattern change with an eventual deepening northern stream trough shifting into the eastern CONUS. An initial shortwave driving this pattern change will evolve eastward across the Northern Rockies and along the International border with ND/MN Tuesday into Wednesday. This will drive a cold front through the area Tuesday night into Wednesday bringing the potential for strong storms in the presence of above normal warmth and pooling low level moisture and instability. The deterministic ECMWF has stayed fairly consistent over the past several nights painting in the QPF the look of a mature MCS developing to our northwest on Tuesday, and then propagating E/SE into the reservoir of instability and deeper moisture across the region Tuesday night. This would most certainly harbor strong wind potential given ramping deep layer shear. However, there is a lot of uncertainty as well and this is largely attributed to the fact that we`re seeing more of a signal that showers and storms could be around the area for much of the day on Tuesday, which if occurs could limit instability and temper subsequent strength of any convection Tuesday night with the cold front. Bottom line, there is at least some potential for strong storms Tuesday/Tuesday night that we`ll continue to re-evaluate in the next couple of days. Stay tuned! The cold front will begin the process of ushering in a cooler airmass, which will be reinforced by an upper trough evolving over the Great Lakes and eastern CONUS by late in the week and heading into next weekend. This is likely to result in mainly dry conditions, and below normal temperatures with pleasant days (highs mainly in the 70s) and cool nights (lows in the 50s to possibly a few 40s). && .AVIATION /18Z TAFS THROUGH 18Z MONDAY/... Issued at 1223 PM CDT Sun Jun 2 2024 The widespread IFR/MVFR conditions of this morning are becoming widespread VFR as of late morning, with the remainder of the day time hours expected to be VFR, though a brief higher end MVFR cig cannot be ruled out through 19Z. Tonight`s rain and thunder chances now appear more marginal, as the focus for storms may remain well to the west of eastern Iowa until late tonight. A veering low level jet will possibly bring this activity eastward after 08z tonight, in a dissipating mode, thus, we have retained a prob30 group for thunder in the 08-12 period in northeast Iowa and reduced it to showers to the southeast in MLI/BRL. Low confidence on showers/thunder remain in place through the day Monday, with most hours dry and VFR after 14z. && .DVN WATCHES/WARNINGS/ADVISORIES... IA...None. IL...None. MO...None. && $$ SHORT TERM...McClure LONG TERM...McClure AVIATION...Ervin