Area Forecast Discussion
Issued by NWS Quad Cities, IA IL
Issued by NWS Quad Cities, IA IL
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610 FXUS63 KDVN 271629 AFDDVN Area Forecast Discussion National Weather Service Quad Cities IA IL 1129 AM CDT Mon May 27 2024 .KEY MESSAGES... - Isolated to scattered thunderstorms possible this afternoon. There is a marginal or level 1 out of 5 risk of severe thunderstorms this afternoon. - Quiet weather is forecast for Wednesday and Thursday with high temperatures ranging from 70 to 75 degrees. - Chances of showers and storms return Friday through Sunday. && .SHORT TERM /THROUGH TUESDAY/... Issued at 229 AM CDT Mon May 27 2024 At 2 AM a cold front sits to our south across northern Missouri with a second cold to our northwest across northern Minnesota and North Dakota. Low clouds across the area are slowly sliding to to our east. A northwest breeze has continued across the area overnight with speeds of 10 to 20 MPH. Temperatures across the area range from 55 degrees at CID to 60 degrees at Moline. A vort max is evident on water vapor imagery early this morning moving into the central Dakotas and is forecast to arrive later this afternoon into this evening as the Upper Midwest remains on the western edge of a trough over eastern Canadian and the northeastern US. This will also drive a cool front across the area. Temperatures ahead of the front are forecast to be in the mid 70s with dewpoints in the mid 50s. Despite the drier airmass most unstable CAPE values of 500 to 1000 J/KG are possible with 30 knots of 0 tp 6 km shear. CAMs are showing the potential for damaging winds. Given the drier atmosphere, expected isolated to scattered coverage for storms today. For this reason, the storm prediction center has much of the area under a marginal risk of severe storms. Showers and thunderstorms will end from west to east this evening with clouds lingering across the area north of Interstate 80. Low temperatures on Tuesday morning will range 50 to 55 degrees. && .LONG TERM /TUESDAY NIGHT THROUGH SUNDAY/... Issued at 229 AM CDT Mon May 27 2024 The long term period begins on Tuesday morning with deep northwest flow aloft as we continue to sit on the edge of a deep trough to our east. This will allow another disturbance to move across the area during the day on Tuesday with scattered showers and storms possible once again. Wednesday through Friday morning a ridge of high pressure will move across the area bringing quiet weather to the area. Temperatures will be pleasant and range from 70 to 75 degrees. Temperatures will warm Friday through Sunday as high pressure moves to the east with highs in the upper 70s to lower 80s by Sunday. A closed 500 MB low is forecast to move across the southern Canadian Plains late this week into next weekend and bring several chances for showers and storms with the best chances (25 to 35%) on Saturday. Dewpoints will remain in the 50s during this period so instability will be somewhat limited. && .AVIATION /12Z TAFS THROUGH 12Z TUESDAY/... Issued at 625 AM CDT Mon May 27 2024 MVFR ceilings have moved to the east of all TAF sites this morning. Another storm system will move across the area this afternoon into the early evening with isolated to scattered showers and storms possible. If showers do occur then MVFR ceilings and visibilities are possible. Decided to continue to use of a prob30s to account for KCID, KDBQ, and KMLI. Expect gusty northwest winds to continue through the day at all TAF sites before winds lower to 5 to 10 knots this evening. Outside of showers and thunderstorms, expect VFR conditions to occur. && .HYDROLOGY... Issued at 1110 AM CDT Mon May 27 2024 Rainfall the past 24 hours was not as widespread as two days ago. Although not as heavy, amounts of 0.5 to 1 inch fell across northeast Iowa and parts of Wisconsin and Illinois. River forecasts have not changed all that much. Crests are working down the tributary rivers of eastern Iowa with new crests working down the tributaries of northern Illinois. The flood watches continues for the Skunk River at Augusta, IA and the Mississippi River at New Boston. Attenuation of the flood crest on the Skunk River brings a lower confidence that flood stage will be achieved at Augusta, Iowa. On the Mississippi, the forecast rise at New Boston is due to a combination of routed flow and the expected Cedar/Iowa flow arriving immediately downstream. The Cedar/Iowa flow will result in backwater effects but there is still some uncertainty regarding the timing of this flow. If the Cedar/Iowa flow and Mississippi routed flow constructively interfere with each other, that is arrive at the same time, then the probability of New Boston achieving flood stage is much higher. If deconstructive interference occurs, that is the flows arrive at different times, the the probability of New Boston reaching flood stage would be lower. Right now the probabilities of New Boston reaching flood stage are about 45-50 percent. After a brief reprieve this week, the active weather pattern will resume next weekend and into the following week. The Climate Prediction Center has a 35-38 percent probability favoring above normal precipitation into the first week of June. && .DVN WATCHES/WARNINGS/ADVISORIES... IA...None. IL...None. MO...None. && $$ SHORT TERM...Cousins LONG TERM...Cousins AVIATION...Cousins HYDROLOGY...08