Short Range Forecast Discussion
NWS Weather Prediction Center College Park MD
400 AM EDT Fri Jul 30 2021
Valid 12Z Fri Jul 30 2021 - 12Z Sun Aug 01 2021
...Strong to severe thunderstorms with locally heavy rain across the
northern Plains today and then toward the Midwest early on Saturday...
...More monsoonal moisture expected across the interior western U.S. with
increasing focus over central Colorado and the northern Great Basin during
...Excessive heat/heat advisories continue for the interior Pacific
Northwest, central U.S. and Deep South while much cooler air overspreads
the Northeast/Great Lakes into the Mid-Atlantic...
A developing low pressure system currently near the New England coast will
move steadily eastward into the Canadian Maritimes today, bringing much of
the heavier rainfall away from New England. A large dome of cool air
behind the low will usher across the Great Lakes and overspread much of
the Northeast and down into the Mid-Atlantic during the weekend. This
will bring welcome relief to the recent spell of summer heat and humidity
across parts of these areas. Before the arrival of the cool air mass
however, some showers and thunderstorms can be expected from upstate New
York to northern New England near and ahead of a reinforcing cold front.
Much of the heat and tropical humidity will be across the central Plains,
the Deep South, and into the Southeast today ahead of the trailing front.
A low pressure wave developing over the central High Plains is forecast to
trigger organized thunderstorms that could become severe today across the
northern Plains before moving toward the Midwest today into Saturday
morning. In addition, heavy rain associated with the thunderstorms could
trigger flash flooding.
Over the western U.S., a persistent ridge of high pressure aloft will
continue to sustain the excessive heat across interior Pacific Northwest
into the weekend. Farther south, monsoonal moisture continues to bring
much needed rainfall to the drought-stricken regions of the western U.S.
The broad area of monsoonal showers and thunderstorms is expected to show
increasing focus across central Colorado as well as spreading further
north into the northern Great Basin during the weekend, where the threat
of heavy rainfall will increase.
Lastly, Air Quality Alerts are currently in effect for portions of Idaho,
Montana, Wyoming, Colorado, Minnesota, and Iowa due to smoke from ongoing
wildfires out west and in Canada being advected into their areas by the
prevailing northerly-northwesterly winds.
Graphics available at www.wpc.ncep.noaa.gov/basicwx/basicwx_ndfd.php