Short Range Forecast Discussion
NWS Weather Prediction Center College Park MD
352 AM EDT Wed Sep 16 2020
Valid 12Z Wed Sep 16 2020 - 12Z Fri Sep 18 2020
...Sally to bring hurricane force winds and life-threatening flash
flooding and storm surge to parts of the Central Gulf Coast...
...There is a high risk of excessive rainfall over parts of the Eastern
...Wildfires and poor air quality continues over parts of the interior
Pacific Northwest, Central California, the Northern Rockies, the Great
Basin, Arizona, and Northern New England...
...Below normal temperatures will move into the Upper Midwest...
The latest forecast for Hurricane Sally from the NHC has Sally onshore
early Wednesday morning. Hurricane force winds, life-threatening storm
surge, very heavy rainfall, and a threat for tornadoes will continue
through Wednesday for portions of the Central Gulf Coast region. Sally is
a slow moving storm producing very heavy rainfall a high risk for
life-threatening and historic flash flooding. As Sally makes her way
slowly inland, significant flash and urban flooding, as well as minor to
moderate river flooding, are likely to spread northward into Alabama,
Northern Georgia, and the Western Carolinas. The WPC has issued a high
risk of excessive rainfall over parts of the Central
Gulf Coast through Thursday morning. The heavy rain and surf associated
with Sally will produce severe, widespread areas of flash flooding, this
will include areas that don't normally experience flash flooding. The
latest forecast storm total rainfall from Sally calls for 10 to 20+ inches
of rain with isolated 35 maximum over parts of Southeast U.S.. Please
refer to the latest advisory from the NHC for additional and updated
information regarding Sally.
Out West and Northeast, dense smoke advisories and air quality alerts
remain in place across much of the Northwest U.S., Great Basin, parts of
Central California, parts of Arizona, and Northern New England. Compared
to recent days, fire weather conditions should continue to improve across
the Western U.S. ahead of a frontal boundary. By Thursday evening into
Friday, some much anticipated rainfall is expected to move into parts of
the Pacific Northwest.
Above average temperatures will continue Wednesday into Thursday over the
Western U.S.. A cold front dropping into the Northern Tier States will
bring a surge of colder temperatures spreading from the Upper Midwest on
Wednesday into Thursday. Daytime highs could be 10 degrees below normal
for some locations within this airmass. Elsewhere, the East Coast should
remain comfortable and near normal the next few days, with below normal
temperatures also expected within areas impacted by Hurricane Sally.
Graphics available at www.wpc.ncep.noaa.gov/basicwx/basicwx_ndfd.php