


Prognostic Meteorological Discussion
Issued by NWS
Issued by NWS
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768 FXUS21 KWNC 141811 PMDTHR US Hazards Outlook NWS Climate Prediction Center College Park MD 300 PM EDT July 14 2025 SYNOPSIS: Mid-level high pressure is forecast across much of the contiguous U.S. (CONUS) during the week-2 period. The center of the mid-level high is forecast across the Great Plains and Mississippi Valley, bringing increased chances of extreme heat to portions of the central CONUS. There is also an enhanced likelihood for heavy precipitation along the northern periphery of the mid-level high for parts of the Great Lakes and Upper Mississippi Valley. HAZARDS Slight risk of extreme heat for portions of the Great Plains, Great Lakes, and the Mississippi, Ohio and Tennessee Valleys, Tue-Mon, Jul 22-28. Slight risk of heavy precipitation for portions of the Great Lakes, Upper and Middle Mississippi Valley and Northern Plains, Tue-Thu, Jul 22-24. DETAILED SUMMARY FOR THURSDAY JULY 17 - MONDAY JULY 21: https://www.wpc.ncep.noaa.gov/threats/threats.php FOR TUESDAY JULY 22 - MONDAY JULY 28: Positive 500-hPa height anomalies are forecast across much of the CONUS during the week-2 period by the GEFS, ECENS, and CMCE model guidance. This elevates chances for above-normal temperatures for much of the CONUS near the climatologically hottest time of year for much of the country. The Probabilistic Extremes Tools (PETs) and short-term bias corrected apparent temperature tools indicate that there are elevated chances (>20%) for maximum temperatures exceeding the 85th climatological percentile and apparent temperatures reaching hazardous criteria for much of the Great Plains, Great Lakes, and Mississippi, Ohio and Tennessee Valleys. A slight risk of extreme heat is posted for these areas for the entirety of the week-2 period as the mid-level high pressure remains in place for much of the period. Guidance from GEFS based tools would support a slight risk of extreme heat for portions of the Interior West. However, the ECENS signal for this heat potential is noticeably weaker, especially at the beginning and middle of the period. The ECENS based tools come into better agreement towards the end of the week-2 period as the mid-level ridge retrogrades into parts of the West. However, model guidance has been consistently predicting this to occur around day 12 for the past several days with the tools consistently slipping day by day. Due to high uncertainty, no associated hazard is posted at this time but the area will be monitored for potential addition of a hazard, if models can come into better agreement earlier in the period. Across the Upper Mississippi Valley and into the Great Lakes there are some increased signals for enhanced precipitation in this region. The ECENS PET has a broad area indicating at least a 20% chance of 3-day accumulated precipitation exceeding the 85th percentile. The GEFS has spottier chances but is in relative agreement. The ECENS raw tool is even more supportive of enhanced precipitation across the region. Finally, the week-2 analog precipitation tool also highlights this region to see above-normal precipitation. This area is forecast to see 1.5 to 3 inches of precipitation during week-1. Any additional precipitation in week-2 would impact an already wet environment. Therefore a slight risk of heavy precipitation is posted for parts of the Upper Mississippi Valley and Great Lakes and surrounding areas, Jul 22-24. FORECASTER: Ryan Bolt $$