Short Range Forecast Discussion
NWS Weather Prediction Center College Park MD
328 PM EDT Mon Oct 04 2021

Valid 00Z Tue Oct 05 2021 - 00Z Thu Oct 07 2021

...Areas of heavy rain and concerns for flash flooding are expected over
the Southeast going through the middle of the week...

...Elevated concerns for wildfire activity will exist over portions of the
northern Great Basin and the northern High Plains going through at least
Tuesday...

...Much above normal temperatures are expected over the northern High
Plains and Upper Midwest over the next few days...

A quasi-stationary front draped generally from areas of the northern
Mid-Atlantic and Ohio Valley southward down to the central Gulf Coast
region will remain largely intact going through the middle of the week and
move very little as the main belt of the westerlies becomes displaced well
to the north over areas of central and eastern Canada. However, there will
be a somewhat cooler pool of high pressure over northern New England that
will nose southward over the next couple of days with the help of low
pressure developing along the front just south of Long Island which will
edge slowly eastward and offshore of southern New England on Tuesday. This
will allow the front to settle a little farther south through areas of the
Mid-Atlantic states over the next couple of days. This wave of low
pressure though will be bringing a steady moderate to locally heavy rain
to areas of southern New England this evening and overnight, with the rain
tapering off Tuesday morning.

Farther down to the southwest, the aforementioned front will be the focus
for scattered to locally broken areas of showers and thunderstorms which
will cover a fairly broad area extending from the middle Mississippi and
Ohio Valleys east through the Mid-Atlantic and south down across the
Tennessee Valley and the Southeast. There is the expectation of seeing an
upper-level low develop toward the middle of the week over the lower
Mississippi Valley and this coupled with the front will maintain the
threat of unsettled weather. The heaviest rainfall is expected to
generally be over the Southeast, and gradually portions of the southern
Appalachians and Tennessee Valley, where locally several inches of rain
are expected to fall over the next few days. There will be at least a
localized threat of flash flooding and especially with the expectation of
seeing slow-moving showers and thunderstorms capable of producing very
heavy rainfall rates. In fact, the Weather Prediction Center has depicted
a Slight Risk of excessive rainfall for each of the next couple of days to
address this concern.

Meanwhile, much-needed moisture will stream into southern California and
the broader Southwest U.S. later tonight and through Tuesday as some
energy over the subtropical east Pacific lifts northeast across Baja
California and then inland into the Southwest. Some locally heavy rains
will be possible, and especially over the Mogollon Rim area of central and
northern Arizona. An isolated concern for flash flooding will be possible
as well and mainly with respect to the burn scar areas.

Given the displacement of the westerlies well to the north over central
and eastern Canada, there will be a lack of cold fronts settling south
from Canada, and thus a large area of the U.S. will see above to much
above normal temperatures going through the middle of the week. This will
especially be the case for areas of the northern High Plains and the Upper
Midwest where daytime temperatures may reach 20 to 25 degrees above normal
over the next few days, with some temperatures locally approaching 90
degrees and possibly setting a couple of records. The very warm
temperatures coupled with dry conditions and gusty winds will also result
in concerns for elevated wildfire activity for portions of the northern
Great Basin and the northern High Plains. Much cooler temperatures though
will be lurking just to the west by Wednesday as a rather strong Pacific
cold front advances inland and crosses through the Pacific Northwest.

Orrison

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