Short Range Forecast Discussion NWS Weather Prediction Center College Park MD 106 AM EST Thu Nov 05 2020 Valid 12Z Thu Nov 05 2020 - 12Z Sat Nov 07 2020 ...Very warm autumn weather continues across much U.S. before a winter storm develops over the interior western U.S. late on Friday... ...Record or near-record heat continues for the Desert Southwest, northern Rockies and the northern Plains Thurs/Fri and into the Upper Midwest by Sat... ...Chances of rain increasing across southern Florida as Eta re-emerges into the northwestern Caribbean Sea... A very expansive upper-level ridge that has been dominating much of the western and central U.S. with 20 to 35 degree above normal temperatures including large areas of potential breaking highs and maximum low daily records will shift eastward day by day, pressing well above temperatures mainly across Northern States where typical autumn weather would have set in across the Upper Midwest by Saturday. However, a large scale weather pattern change is finally coming for the west with the development of strong dip in the jet streak leading to a strong surface cyclone across the Great Basin and Snake River Plain late Friday into Saturday. Prior to this development, waves of Pacific moisture will continue through Thursday and Friday into the Pacific Northwest, eventually dropping south across southern Oregon and northern California Friday morning. Colder maritime air will surge in and lower snow levels across the Cascades into the Sierra Nevada by early Saturday; Winter Weather Advisories are up for the Friday night across the Trinity and Siskiyou Ranges of N California and a Winter Weather Watch is in effect across the highest elevations of the Sierra Nevada into Saturday. Over the northern and central High Plains, blustery winds combining with very warm and dry conditions will raise the fire risk across the area into Thursday. Fire Risk including Red Flag Warnings are also in effect across much of Southern Nevada and adjacent deserts of Eastern California where increasing winds and ample dry fuels/low relative humidity values increase fire danger. Across southern Florida, the chance of tropical downpours and thunderstorms will gradually increase during the next couple of days as a long fetch of Atlantic moisture north of an old stationary front will lift northward as Eta is forecast to move back over the northwestern Caribbean Sea and regenerate. Given the circulation of Eta has weakened and moved inland, there is greater than normal uncertainty within the the future development track and intensity, so please refer to the National Hurricane Center frequently for the latest on Eta. Gallina Graphics available at www.wpc.ncep.noaa.gov/basicwx/basicwx_ndfd.php