Short Range Forecast Discussion
NWS Weather Prediction Center College Park MD
225 PM EDT Sat Jun 16 2018
Valid 00Z Sun Jun 17 2018 - 00Z Tue Jun 19 2018
...Strong to severe thunderstorms along with heavy rain and areas of flash
flooding can be expected from parts of the Central and Northern Plains to
the Upper Midwest and Upper Great Lakes...
...Very wet conditions expected for portions of the Gulf Coast, Southwest,
Great Basin and Northern Rockies...
...Dangerous heat and humidity will be in place through the weekend over
much of the Midwest and spreading to the East Coast by early next week...
Several rounds of heavy showers and strong thunderstorms are expected to
impact much of the northern tier states over the next couple of days,
including a fairly large area of the Central and Northern Plains and east
over to the Upper Midwest and Upper Great Lakes region as multiple waves
of low pressure lift up along a frontal zone draped across the region.
Some of the thunderstorms may severe during especially the afternoon and
evening hours, and there will also be concerns for flash flooding given
the multi-day threat of heavy rainfall and slow movement of the front down
to the southeast across the Midwest. In fact, locally several inches of
additional rain will be expected and especially areas of Minnesota,
Wisconsin and the Upper Peninsula of Michigan and this is where the
Weather Prediction Center has locally indicated a Moderate Risk of
excessive rainfall going through early Sunday. The Storm Prediction Center
meanwhile has portions this area also highlighted in an Enhanced Risk for
severe weather going through tonight.
Meanwhile, areas south and east of this front are expected to see very hot
and muggy conditions, including many areas of the Southern and Central
Plains, and the Midwest. Afternoon highs will generally range from the 90s
to low 100s, and with the high humidity, this will promote dangerously
high heat indices of that may reach as high as 105 to 110 degrees. Some
major Midwest cities to be impacted by this include Minneapolis, MN;
Chicago, IL; and St. Louis, MO. Some of this high heat and humidity will
be arriving along the Eastern Seaboard by Monday including New England and
the Mid-Atlantic where high temperatures will be well into the 90s.
There will be unsettled weather developing also for the Gulf Coast states
and especially areas of southeast Texas and Louisiana by Sunday and Monday
as a surge of tropical moisture in off the Gulf of Mexico and the arrival
of a trough of low pressure help to bring numerous showers and
thunderstorms to the region. This will be beneficial rainfall overall as
the region has been dry and is locally in a drought. However, several
inches of rain are expected, and this area will need to be very closely
monitored for flash flooding should heavier rainfall amounts materialize.
The remnants of former tropical cyclone Bud meanwhile continue to lift
north up across the Southwest and with this will be a significant influx
of tropical moisture. Areas of heavy rainfall are expected through tonight
and Sunday across areas of southern and eastern Arizona, southeast Utah,
Colorado and New Mexico. This moisture arrival is well ahead of the
typical onset of the monsoon season, be it should be largely beneficial as
it will help to alleviate some of the ongoing drought and wildfire
concerns. Nevertheless, the rain may be heavy enough to cause concerns for
flash flooding as well. The Weather Prediction Center has highlighted a
Slight Risk of excessive rainfall for portions of this region.
Elsewhere across the West, a deep trough of low pressure will be evolving
over the next couple of days which will allow temperatures across the
Great Basin and northern High Plains to cool substantially and be much
below normal. In fact, high temperatures will be as much as 10 to 20
degrees below normal. There will also be plenty of clouds and locally
heavy rainfall across the northern Great Basin and Northern Rockies which
may also result in some localized flooding concerns.
Graphics available at www.wpc.ncep.noaa.gov/basicwx/basicwx_ndfd.php