Extended Forecast Discussion NWS Weather Prediction Center College Park MD 314 PM EDT Thu Jul 10 2025 Valid 12Z Sun Jul 13 2025 - 12Z Thu Jul 17 2025 ...Daily heavy rain threats are forecast for the Florida Peninsula Monday through Thursday... ...Overview... Upper ridging remains anchored over the Southwest through Tuesday while troughing shifts from the Great Lakes to the Northeast. A zonal northern stream jet over southwest Canada amplifies into a trough over the northern Rockies by Tuesday before drifting east over the northern Plains through midweek. The developing trough will send a cold front over the central U.S. with shortwave activity aiding summertime convective storms over much of the country east from the Rockies. ...Guidance/Predictability Assessment... There is decent global agreement on longer wave features through the forecast period. A general slowing trend to the early to mid week trough progression over the north-central CONUS is noted while a more progressive solution for the Great Lakes/Northeast trough is preferred. A general model blend preference works to begin the period, then to avoid the quicker GFS for the north- central trough. Ensemble means were used to fill the gaps beyond the UKMET and when the GFS share was reduced. ...Weather/Hazards Highlights... A frontal system from a trough drifting east from the central Great Lakes on Sunday will provide a focus for convection from Upstate New York through the Ohio Valley, the Mid-South, southern Plains, to west Texas and the southern Rockies. A Day 4 Marginal Risk is maintained across this area with a shift eastward to the Northeast per updated consensus on a faster timing. Similar conditions are expected for Day 5 with a further shift east for the Northeast, with a repeat for the Mid-South, southern Plains, west Texas, and southeast New Mexico where the Marginal Risk was expanded through. Abundant moisture will feed into Florida beginning Sunday, but increasing by Monday thanks to a broad subtropical ridge. Heavier than normal diurnal activity can be expected there through at least Thursday with risks for flash ponding/flooding. The Day 4 Marginal Risk was shrunk a bit based on less coverage/intensity forecast, but it is maintained for Day 5 (with an expectation for at least a Marginal Risk for what is currently Days 6/7). A second frontal system is anticipated to enter the north-central states early next week and will usher in the next round of rain and below normal temperatures. Given the recent rains across parts of the Dakotas and Minnesota, soils require less moisture before rain becomes excessive. The Day 5 Marginal Risk area for this part of the country was expanded a bit given the 12Z guidance consensus. Hot weather will remain for much of the western U.S. through Monday as upper ridging persists. Daily maximums will be above normal with many locations climbing into the 100s and 110s for the Desert Southwest, and nearing/exceeding 100F farther north in interior/lower elevation areas of the Great Basin. However, as a trough develops over the northern Rockies late Monday, temperatures will quickly drop below normal for the northern Plains where current projections are for high temperatures 15 to 25 degrees below normal for Tuesday and Wednesday. Temperatures look to be a few degrees cooler than average for the south- central U.S. for much of next week as clouds and rain hold temperatures down. The Northeast will see a return to above normal temperatures on Tuesday after the trough clears. Meanwhile the Southeast should be near normal to a few degrees above, for typical summer heat and humidity. Jackson Additional 3-7 Day Hazard information can be found on the WPC medium range hazards outlook chart at: https://www.wpc.ncep.noaa.gov/threats/threats.php WPC medium range 500mb heights, surface systems, weather grids, quantitative precipitation forecast (QPF), excessive rainfall outlook (ERO), winter weather outlook (WWO) probabilities, heat indices, and Key Messages can be accessed from: https://www.wpc.ncep.noaa.gov/medr/5dayfcst500_wbg.gif https://www.wpc.ncep.noaa.gov/medr/5dayfcst_wbg_conus.gif https://www.wpc.ncep.noaa.gov/5km_grids/5km_gridsbody.html https://www.wpc.ncep.noaa.gov/qpf/day4-7.shtml https://www.wpc.ncep.noaa.gov/#page=ero https://www.wpc.ncep.noaa.gov/wwd/pwpf_d47/pwpf_medr.php?day=4 https://www.wpc.ncep.noaa.gov/heat_index.shtml https://www.wpc.ncep.noaa.gov/#page=ovw