FXUS63 KDVN 021058 AFDDVN Area Forecast Discussion National Weather Service Quad Cities IA IL 558 AM CDT Fri May 2 2025 .KEY MESSAGES... - Periodic chances of showers and isolated thunderstorms will remain in the picture today through the upcoming weekend, primarily for locations south and east of the Quad Cities. Strong to severe storms are not anticipated. - Seasonal temperatures are expected through the upcoming weekend, with above normal temperatures returning Tuesday and Wednesday next week. && .SHORT TERM /THROUGH TONIGHT/... Issued at 312 AM CDT Fri May 2 2025 Periodic chances of showers and perhaps an isolated thunderstorm will be sticking around our area, thanks to a few embedded mid-level shortwave impulses that will move through our region from the central Plains, as evident on the latest GOES-East mid-level water vapor imagery. This is all part of a longer wave upper-level trough that continues to slowly progress eastward over the north-central CONUS. Radar is mostly dry, except for a few exiting showers over northwest IL as of 08z/3 AM this morning. An expanding area of stratus has developed across our northern areas early this morning, but south of this stratus should be predominantly clear skies, so some of us over southeastern IA into west-central IL could see some sunshine to start the day. However, those shortwaves will arrive this afternoon, leading to increasing chances (30-60%) of showers and possibly an isolated storm mainly south of Interstate 80. Instability looks to be pretty meager, with MLCAPE at best up to 500 J/kg this afternoon. Mid-level lapse rates aren't too concerning either, generally around 6-7 C/km, so some small hail can't be ruled out with any robust convection that does develop. Seasonal high temperatures will continue today, warming to around 60 north to the upper 60s southeast. The trough will continue to translate eastward, so chances (20-50%) of showers will continue tonight, mainly for locations along and east of the Mississippi River, with lows in the lower to middle 40s. && .LONG TERM /SATURDAY THROUGH THURSDAY/... Issued at 312 AM CDT Fri May 2 2025 As we head into the day Saturday, the upper-level trough will become cut-off aloft and is now progged to set up south of Lake Michigan through the weekend into Monday. A dProg/dt analysis of this upper- level low position among the GFS deterministic and LREF ensemble guidance indicates a closer position to our region than it was around 24 hours ago, so it is more likely that we will see more cloudiness than we thought just a few days ago. In terms of precipitation chances through Sunday, they will mainly be confined to locations along and east of the Mississippi River, particularly south and east of the Quad Cities, as a few PVA maxima pivots near the area. This activity should remain as rain showers as instability appears to be too low to support thunderstorms. We will continue to see seasonal temperatures into Monday, with highs in the 60s and lows in the 40s. The cut-off low does appear to finally shift eastward Monday night, leading to a period of dry conditions Tuesday, thanks to high pressure ridging aloft. More favorable diabatic heating from insolation should help temperatures warm to the lower to middle 70s on Tuesday and Wednesday. For Wednesday and Thursday, guidance indicates another mid-level shortwave to approach the region from the west. However, there are some discrepancies about the onset timing of this wave and attendant precipitation. Ensemble cluster analysis indicates some varied amplitudes of the approaching wave and its morphology, so confidence remains low this far out. However, NBM consensus blends maintain 20-30% chances of showers Wednesday and Thursday - a pretty weak signal for robust showers, but can't rule them out entirely. Again, no concerns for any strong to severe convection at this time during this period. && .AVIATION /12Z TAFS THROUGH 12Z SATURDAY/... Issued at 558 AM CDT Fri May 2 2025 MVFR ceilings continue across our north, including the DBQ TAF terminal this morning as a low stratus deck continues to pivot across our north. The latest nighttime microphysics satellite imagery shows this stratus very well, and it seems to have just missed CID as of TAF issuance, but it looks to have the right trajectory for impacting MLI over the next few hours, so I have put in a TEMPO group of MVFR cigs there. Otherwise, VFR conditions were seen across the remainder of the region. Ceilings will eventually improve area-wide to VFR, with another round of scattered showers and perhaps an isolated thunderstorm possible this afternoon and evening. Confidence in the exact coverage/timing remains a bit low, but it seems to be higher the farther south you go, so used a TEMPO group for BRL to convey the most likely timing of these showers, with PROB30s elsewhere. MVFR conditions will be possible with this activity. && .DVN WATCHES/WARNINGS/ADVISORIES... IA...None. IL...None. MO...None. && $$ SHORT TERM...Schultz LONG TERM...Schultz AVIATION...Schultz