Short Range Forecast Discussion
NWS Weather Prediction Center College Park MD
332 AM EDT Thu Jun 08 2023

Valid 12Z Thu Jun 08 2023 - 12Z Sat Jun 10 2023

...There is a Slight Risk of excessive rainfall over parts of the Northern
Intermountain Region/Northern Rockies into the Northern High Plains by
Friday...

...Air Quality Alerts over parts of the Great Lakes/Ohio Valley to the
Northeast and Mid-Atlantic...

...Temperatures will be below average over parts of California/Southwest
and the Northeast into the Ohio Valley/Mid-Atlantic...

Upper-level impulses and moisture trapped under an upper-level ridge from
the North Intermountain Region to the Upper Mississippi Valley and
southward to the South Rockies to the Central Gulf Coast will produce
showers and thunderstorms through Saturday. Some of the showers and
thunderstorms will create heavy rain over parts of Idaho, Washington
State, Oregon, Montana, and Wyoming. Therefore, the WPC has issued a
Slight Risk of excessive rainfall over parts of the Northern Intermountain
Region/Northern Rockies through Friday morning. The associated heavy rain
will create mainly localized areas of flash flooding, with urban areas,
roads, and small streams the most vulnerable.

On Friday, the threat of excessive rainfall elongates into the South
Dakoda. Therefore, the WPC has issued a Slight Risk of excessive rainfall
over parts of the Northern Rockies/Northern High Plains and Northern
Plains from Friday into Saturday morning. The associated heavy rain will
create mainly localized areas of flash flooding, with urban areas, roads,
and small streams the most vulnerable.

Moreover, an upper-level low over Great Basin/Southwest will slowly move
northward to the Northern Intermountain Region while weakening, as a
second upper-level low over the Eastern Pacific moves to the Northern
California Coast by Saturday. As a result, the system will produce showers
and thunderstorms over parts of California and the Pacific Northwest/Great
Basin through Saturday. The upper-level troughing will aid in keeping
temperatures below average in parts of California/Southwest. Additionally,
a weak front will move southward from the Southeast, Tennessee Valley, and
Middle/Lower Mississippi Valley to the Central Gulf Coast, Lower
Mississippi Valley, and Southern Plains by Saturday. Showers and
thunderstorms will develop along and ahead of the boundary on Thursday
into Saturday morning.

Meanwhile, an upper-level low over New England continues over the region
through Saturday. On Thursday, rain and drizzle will develop over parts of
the Northeast through Saturday. The upper-level low will aid in keeping
temperatures below average in parts of the Northeast into the Ohio
Valley/Mid-Atlantic.

Wildfire smoke moving southward out of Canada and over the northern part
of the country has triggered Air Quality Alerts over parts of the Great
Lakes/Ohio Valley to the Northeast and Mid-Atlantic. The air quality will
be decreasing over Alabama and Georgia on Thursday.


Ziegenfelder



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