Short Range Forecast Discussion
NWS Weather Prediction Center College Park MD
306 PM EDT Sat Jun 18 2022

Valid 00Z Sun Jun 19 2022 - 00Z Tue Jun 21 2022

...Dangerous heat to continue throughout the Deep South and surge across
the northern Plains/Upper Midwest through Monday, while considerably
cooler temperatures are forecast over the Northeast and West...

...Early monsoon moisture to lead to isolated chances for flash flooding
across parts of the Southwest, Four Corners region, and central/southern
Rockies, with Critical Fire Weather located from northwest Arizona into
portions of the central Great Basin...

...Scattered severe thunderstorms and isolated instances of flash flooding
possible over parts of the northern Rockies and northern High Plains
through the end of the weekend...

A significantly amplified jet stream pattern that features a deep trough
in the West, a strong ridge in the Heartland, and a second anomalous
trough over the Northeast will be the primary driver in the resulting
weather throughout the Lower 48 into early next week. The hottest
temperatures versus normal will be positioned in the northern/central
Plains and Upper Midwest, where high temperatures will run 20 to 30
degrees above average and soar into the upper 90s and low 100s. Excessive
Heat Watches and Heat Advisories have been posted due to maximum heat
indices ranging between 100-110 degrees. The anomalous heat will gradually
shift eastward out of the northern Plains and into the Upper Mississippi
Valley by Monday. Hazy, hot, and humid conditions are also on tap in the
Deep South, resulting in the issuance of Heat Advisories from central
Florida to the Lower Mississippi Valley through this evening. High
temperatures along the Gulf Coast are forecast to range from the mid-90s
to the century mark for the foreseeable future, with lows only dipping
into the upper 70s. In contrast, the West Coast, Great Lakes, and
Northeast will experience considerably cooler than normal temperatures on
Sunday and Monday. Daytime highs will struggle to get out of the 60s in
the Pacific Northwest and New England on Father's Day, which for June 19
runs about 15-20 degrees below normal. The cool June weather will have a
chance to break a few minimum temperature records during the early morning
hours on Sunday, especially in the central Appalachians and northern
Mid-Atlantic.

In terms of unsettled weather, the most active areas will be around the
periphery of the heat dome positioned over the Nation's Heartland.
Starting in Florida, an approaching cold front from the north and tropical
moisture aloft will lead to diurnally driven widespread showers and
thunderstorms through Sunday evening. Rainfall rates may be heavy enough
to lead to flash flooding in spots, prompting Marginal Risks for Excessive
Rainfall to be issued in central/southern parts of The Sunshine State. A
few thunderstorms may turn severe and produce damaging wind gusts as well.
In the Southwest, a surge in monsoonal moisture is set to trigger numerous
showers and storms throughout the Four Corners region, especially in the
higher elevations across eastern Arizona, New Mexico, and southern
Colorado. Marginal Risks for flash flooding are also in place in these
states with burn scar regions at highest risk for flash flooding.
Elsewhere, the slow moving upper trough in the Pacific Northwest will
spawn showers and thunderstorms from the Pacific Northwest to the northern
High Plains. The wettest Day will be Father's Day where anomalous moisture
and the close proximity of the upper low will support heavier rainfall
rates and potentially severe weather from central Montana to western North
Dakota. Some thunderstorms are also possible in the northern Great Lakes
along a lifting warm front Father's Day afternoon. Lastly, a lifting
occluded low will lead to lingering unsettled weather throughout northern
New England.

Fire weather remains an issue in the Southwest and central High Plains
through Sunday. A Critical Risk for fire weather is in place over the
central Great Basin this evening, with another Critical Risk issued on
Father's Day over southern Utah and northern Arizona. The central High
Plains will witness favorable fire weather conditions as well, resulting
in Elevated Risks. Lastly, high pressure will result in mostly dry
conditions in the Mid-Atlantic, Ohio and Middle Mississippi Valleys, and
much of southern and central California.

Snell

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