Short Range Forecast Discussion
NWS Weather Prediction Center College Park MD
301 PM EDT Sun May 14 2023

Valid 00Z Mon May 15 2023 - 00Z Wed May 17 2023

...Above-normal temperatures to spread from the western into the central
U.S. early this week...

...Additional heavy rain and flooding possible for parts of the southern
Plains and mid Mississippi Valley into Monday...

...Heavy rainfall threat moving east into the lower Ohio and Tennessee
Valleys on Tuesday...

Above-normal temperatures are forecast to persist along the West Coast
through the period while extending across the Intermountain West and into
the Rockies early this week.  For many locations, daytime temperatures
will reach 10-20 degrees above normal on both Monday and Tuesday.  While a
weak area of low pressure in the upper levels of the atmosphere may
provide some relief and an increasing chance for showers and
thunderstorms, high temperatures may once again exceed their daily records
for parts of the Pacific Northwest, including the Seattle and Portland
metro regions, on Monday. 

Energy in the upper levels of the atmosphere interacting with a moist
airmass will continue to produce areas of showers and thunderstorms
through this evening into Monday across the central and southern Plains
and mid Mississippi Valley.  Some of these storms may become strong to
severe, producing large hail damaging winds, as well as heavy to excessive
rainfall.

High pressure to the north will support above-normal temperatures across
the northern Plains and Upper Midwest on Monday, that will extend farther
south on Tuesday.

By early Tuesday, an area of low pressure is expected to strengthen and
move east through the Tennessee and lower Ohio Valley regions.  While
drier conditions are expected for much of the central Plains and mid
Mississippi Valley, the threat for heavy rain is likely to increase across
parts of the Tennessee and lower Ohio Valleys into the southern
Appalachians on Tuesday. 

It will be another cold morning on Monday across the Great Lakes and
Northeast, with frost advisories in effect for parts of western and
northern New York, northwestern Pennsylvania, and northern Vermont. 
Temperatures are expected to rebound before a strong cold front drops into
the region on Tuesday.

Pereira

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