Short Range Forecast Discussion
NWS Weather Prediction Center College Park MD
315 AM EDT Mon Jun 27 2022

Valid 12Z Mon Jun 27 2022 - 12Z Wed Jun 29 2022

...Heavy rain may lead to additional instances of flash flooding over
parts of the Southwest and southern Rockies through at least Tuesday...

...Isolated chances for excessive rainfall forecast across the East Coast
today and Southeast/Gulf Coast States through midweek, with isolated
chances for severe weather located across the northern Plains and Upper
Midwest on Tuesday...

...Above average temperatures and summer heat to impact much of the West
today before shifting into the northern/central Plains by Wednesday...

After a wet and stormy several days across the Southwest and southern
Rockies, additional showers and thunderstorms are forecast to start the
workweek. Anomalous atmospheric moisture content will allow for
thunderstorms to contain intense rainfall rates, which could lead to
isolated-to-scattered flash floods. A Slight Risk (level 2/4) of excessive
rainfall has been issued for today across much of central and western New
Mexico. Once again, areas near burn scars will be most at risk to impacts
from scattered downpours. Heavy rain chances are forecast to become more
isolated and shift slightly southward on Tuesday.

A potent cold front gradually completing its trek across the Nation will
spark scattered thunderstorms from the East Coast to the Deep South today.
The greatest threat from these storms will be associated with heavy
rainfall and frequent lightning. Isolated instances of flash flooding
cannot be ruled out, especially in urban regions. A warm and humid airmass
located across the Deep South will also set up an environment conducive
for scattered pop-up thunderstorms that may produce torrential rain at
times. This airmass and the aforementioned frontal boundary are expected
to linger near the Gulf Coast and Southeast through midweek. Thus, the
forecast is expected to remain similar each day and include continuing
chances for thunderstorms and isolated chances for flash flooding.
Elsewhere, a cold front entering from south-central Canada may spark
severe weather across the Upper Midwest on Tuesday. At the same time a
separate system entering the Pacific Northwest and ejecting into the
northern Plains could create a similar severe risk across northern/central
Montana. Isolated damaging wind gusts and large hail are expected to be
the main hazards within the developing thunderstorms.

The final days of June will feature more heat across parts of the country,
but also some relief for others. A strong upper-level ridge situated over
the West Coast today will allow for widespread above average temperatures
to stretch from California and the Pacific Northwest to the Intermountain
West. Away from the immediate coast and mountain ranges, highs are
forecast to reach into the 90s and low 100s. Scattered Heat Advisories
have been issued for parts of California, Oregon, and Washington. These
above average temperatures are forecast to shift eastward and into the
northern/central Plains by Wednesday. Highs are expected to top out near
the century mark across parts of Nebraska and South Dakota, which equates
to 15-20 degrees above average compared to normal late-June temperatures.
Conversely, the aforementioned cold front has ushered in cooler and drier
air across most of the central and eastern U.S. to start the week. High
temperatures are forecast to remain comfortable and range from the low 70s
to low 80s between the southern Plains and Northeast. A slow warming trend
will commence for most locations on Tuesday, but remain near average and
include pleasant weather through midweek.

Snell

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