Short Range Forecast Discussion
NWS Weather Prediction Center College Park MD
333 PM EDT Sat Sep 16 2023

Valid 00Z Sun Sep 17 2023 - 00Z Tue Sep 19 2023

...Conditions improve across New England tonight and Sunday as Lee exits
into Atlantic Canada...

...Shower and storm chances through the start of the workweek from the
Southern Plains to the East Coast with some locally heavy rainfall
possible...

...Much above average highs expected for the Northern Great Basin and
Northern Plains along with a Critical Risk of Fire Weather on Sunday...

Post-Tropical Cyclone Lee continues on a northward trajectory this
afternoon as it nears the western tip of Nova Scotia and the Bay of Fundy,
while producing moderate rainfall and gusty winds across eastern Maine. As
Lee exits into Atlantic Canada tonight, rainfall and blustery conditions
should rapidly improve by Sunday. However, impacts from dangerous surf and
gusty winds will continue through at least this evening thanks to Lee's
massive wind field. Scattered tree damage and power outages are expected
due to the strong winds, especially throughout parts of Maine. Additional
rainfall amounts of 1 to 2 inches are possible across portions of eastern
Maine, which may lead to localized urban and small stream flooding.

Dry and tranquil conditions extending from the Northeast to the
Mid-Atlantic and Ohio Valley today will be replaced with unsettled weather
on Sunday and Monday as a pair of frontal systems swing eastward from the
Midwest and Deep South. Isolated instances of flash flooding are possible
tonight across the central/southern Appalachians and Tennessee Valley as
scattered downpours enter into sensitive terrain, while also moving at a
relatively slow pace. A stationary boundary draped to the south across the
Gulf Coast and Southern Plains will aid in continuing scattered
thunderstorms from Florida to South Texas this evening, with the threat
shifting towards the Southeast and Mid-Atlantic on Sunday. The main
weather hazard associated with these storms will be the potential for
locally heavy rain and flash flooding, as well as an isolated risk for
damaging wind gusts and tornadoes (especially along the immediate
Southeast coastline on Sunday). By Monday, a more organized area of low
pressure is forecast to develop off the Mid-Atlantic coast and may track
close enough to southern New England on Monday night to provide the
potential for another round of heavy rain across this waterlogged region.

Mostly pleasant weather conditions underneath high pressure is forecast
through the central U.S. into the beginning of the workweek. Meanwhile,
above average temperatures throughout the Pacific Northwest and northern
Rockies this afternoon are expected to spread into the northern Plains by
Monday, with highs into the upper 80s. These warm temperatures will allow
for low relative humidity and when combined with gusty winds, Critical
Fire Weather conditions are possible across the high plains of northwest
Montana on Sunday.

Snell

Graphics available at
https://www.wpc.ncep.noaa.gov/basicwx/basicwx_ndfd.php