![National Oceanic and Atmospheric Administration](/build/images/header/noaa.d87e0251.png)
![National Weather Service](/build/images/header/nws.4e6585d8.png)
![United States Department of Commerce](/build/images/header/doc.b38ba91a.png)
Quantitative Precipitation Forecast
Issued by NWS
Issued by NWS
635 FOUS30 KWBC 251603 QPFERD Excessive Rainfall Discussion NWS Weather Prediction Center College Park MD 1203 PM EDT Tue Jun 25 2024 Day 1 Valid 12Z Mon Jun 24 2024 - 12Z Tue Jun 25 2024 ...THERE IS A SLIGHT RISK OF EXCESSIVE RAINFALL ACROSS PARTS OF MIDWEST... 16Z update... Due to ongoing severe comms issues graphics and other data are largely unable to update. For the Southwest, with the peak heating of the day showers and thunderstorms are expected to fire up across the region this afternoon and continue through the evening hours. These slow moving storms will increase the risk for localized flash flooding concerns, especially over favored sensitive terrain. For the Midwest, a west-east line of storms span from southern Iowa to northern Ohio this morning have brought moderate to heavy rain over some of the same areas from yesterday. Redevelopment is anticipated roughly between 3 and 7pm across north-central portions of the Iowa that will have the potential to produce high rainfall rates over near/over-saturated soils, thus aggravating any flooding over the area. Campbell ...Southwest... PW values will remain highly anomalous (above the 95th climatological percentile and +5 standard deviations) from southern California into the Southwest with a continuation of weak forcing under the upper ridge axis stretching from the Southern/Central Plains into the Southwest. An influx of deeper moisture throughout the mid-levels associated with a tropical disturbance over Mexico. This added moisture when combined with sufficient instability should create greater coverage in convection through the afternoon and evening hours. The sensitive urban locations in and around Tucson prompts a greater risk for scattered flash floods and runoff issues. The trend of slow- moving convection occurring across sensitive terrain is expected to persist which may lead to isolated heavy rainfall and flooding concerns across the broad region of the Southwest and Four Corners. ...Upper Mississippi Valley/Upper Great Lakes... The surface frontal boundary oriented northwest to southeast from the Northern Plains into the Mid Missouri Valley begin to push back to the northeast toward the Upper Mississippi Valley/Upper Lakes region. Strengthening south-southwesterly low level flow into this front will raise PW values to 1.5-2" along and to the northeast of the front. Shortwave energy pushing eastward across the Northern Plains toward the Upper Mississippi Valley will help strengthen isentropic lift over this front and support for overrunning convection. There is not a lot of agreement on placement of any heavy precip totals, but overall some potential given the favorable MCS set up. There is potential for heavy rains to overlap where recent heavy rains fell across southern MN/northern IA and into northern IL. Snell/Oravec Day 2 Valid 12Z Tue Jun 25 2024 - 12Z Wed Jun 26 2024 ...THERE IS A SLIGHT RISK OF EXCESSIVE RAINFALL ACROSS PORTIONS OF THE NEW MEXICO... In the wake of the warm front pressing northeastward across the Upper Mississippi Valley/Upper Lakes region, the associated cold front will be dropping southeast from the Northern Plains into the Upper Mississippi Valley/Upper Lakes during this period. Additional convection likely to develop in the axis of high PWs pooling along the front that becomes more west to east oriented. Convection may train in a west to east direction parallel to this front as the low level flow will also be westerly along and ahead of the boundary. There still is spread in model qpf details, but the multi model ensemble qpf mean and latest NBM do show potential for heavy amounts across areas of far southern WI/eastern IA and northern IL that have received heavy rainfall recently. A broad marginal risk spans from the central Gulf Coast, portions of the Tennessee/Ohio Valleys and most of the Northeast. ...Southwest... No significant large scale changes expected during this period over the Southwest besides the gradual northward lifting of anomalous PWs into parts of UT. PW values 3-4+ standard deviations above the mean will persist from southern California, into the Southwest and southern Great Basin in a region of continued weak forcing under the building closed high over the Southwest. Widespread scattered diurnal convection again possible across these areas, with continued low confidence in any qpf details. There is some elevated concern that convection could be widespread enough to create scattered flash flooding throughout the slot canyon region of south-central Utah. This area will likely be monitored for a targeted upgrade over the next few days should sufficient instability show up in CAMs and greater qpf coverage. Snell/Oravec Day 3 Valid 12Z Wed Jun 26 2024 - 12Z Thu Jun 27 2024 ...THERE IS A SLIGHT RISK OF EXCESSIVE RAINFALL ACROSS PORTIONS OF THE NORTHERN AND CENTRAL PLAINS AND FOR PORTIONS OF NEW MEXICO, COLORADO AND FAR SOUTHERN WYOMING... A low pressure system and associated fronts tracking into the Northern Plains Thursday will bring a threat for heavy rainfall across the north-central Plains into the Upper Midwest. Some conflicting signals remain regarding locations that may see significant rainfall, but latest guidance is suggesting two areas of relatively greater focus during the period. One is within the existing Slight Risk area over parts of the Midwest with a modest southwestward adjustment per latest guidance, and another farther north across northern North Dakota and far northwestern Minnesota where a Slight Risk area has been introduced. Slight Risk areas within the broader Marginal Risk are subject to change based on updated forecasts of convective evolution and location relative to areas with greatest sensitivity due to prior heavy rainfall. Santorelli/Campbell Day 1 threat area: https://www.wpc.ncep.noaa.gov/qpf/94epoints.txt Day 2 threat area: https://www.wpc.ncep.noaa.gov/qpf/98epoints.txt Day 3 threat area: https://www.wpc.ncep.noaa.gov/qpf/99epoints.txt