Short Range Forecast Discussion
NWS Weather Prediction Center College Park MD
329 PM EDT Fri May 05 2023

Valid 00Z Sat May 06 2023 - 00Z Mon May 08 2023

...Active weather pattern from the Pacific Northwest to the Midwest;
severe storms expected across Great Plains and Mississippi Valley...

...Summer-like heat to engulf the Southern/Central Plains and Middle
Mississippi Valley this weekend with some record breaking high
temperatures possible...

...Cooler than normal temperatures to stick around in the West; Critical
Fire Weather in the Southwest and Southern Plains this weekend...

The weekend will kickoff with showers and thunderstorms from the Northwest
to the Central Plains tonight beneath a large mean upper-level trough with
embedded shortwaves rotating around it. Heavy rainfall will focus along
and around a stationary front draped across the Northern
Plains/Rockies/Great Basin, where we have a marginal risk of excessive
rainfall leading to flash flooding in effect through tonight. Some 24 hour
totals of over 2 inches are possible for parts of northwestern Montana and
far northern Idaho by Saturday afternoon/evening. Warm temperatures should
contribute to snowmelt which in turn will exacerbate any flooding concerns
brought on by rainfall. Downstream, some thunderstorms that develop along
the stationary front could turn severe over parts of northeastern
Colorado, western and central Nebraska and northwestern Kansas this
afternoon/evening. The Storm Prediction Center highlighted this area for a
Slight Risk due to the potential for slow moving supercells capable of
producing very large hail and damaging winds.

Elsewhere, shortwave energy will promote additional excessive rainfall
risk over portions of the Southern Plains and Lower Mississippi Valley
tonight where thunderstorms, some severe, could generate high enough
rainfall rates to produce flash flooding. The Storm Prediction Center
highlighted portions of central Texas for a Slight Risk due to the
potential for large hail and locally damaging winds. The next shortwave
will emerge over the Southern Plains on Saturday. The continued presence
of a dry line oriented north-south across central Texas as well as
southeasterly flow bringing Gulf moisture could lead to another round of
severe thunderstorms over portions of southern Oklahoma into central Texas
where the Storm Prediction Center issued a Slight Risk. Severe
thunderstorms capable of producing very large hail and damaging gusts are
possible over the aforementioned areas Saturday afternoon into early
evening. An emerging wave of surface low pressure from the Central Plains
could generate severe thunderstorm activity capable of producing hail and
damaging gusts over parts of the Middle-Mississippi Valley Saturday
morning and afternoon. Heavy rainfall is possible over the central Gulf
Coast on Saturday as a shortwave swings through the region. Scattered to
isolated showers and thunderstorms spread across much of the Mississippi
Valley on Sunday with another area of severe weather possible over much of
Iowa and northern Missouri that afternoon/evening. The Storm Prediction
Center issued a Slight Risk of Severe Thunderstorms for the aforementioned
areas due to the potential for large hail and damaging winds from any
severe storms that do develop.

Upper-level ridging will be responsible for anomalous warmth expanding
across the Southern/Central Plains and into the Midwest this weekend.
Temperatures in the upper 80s to low 90s could rival high temperature
records over parts of the Middle Mississippi Valley on Saturday and
Sunday. Warm, dry and windy conditions this weekend will promote fire
weather in the Southwest and Southern Plains, where Critical Fire Weather
Outlooks were issued by the Storm Prediction Center. Conversely, mean
troughing in the West will contribute to below average high temperatures
on the order of 15-25 degrees below average over much of California and
the Great Basin this weekend. The cold air will support heavy snowfall
potential over the highest elevations of the Sierra Nevada on Saturday.
Temperatures in the East will begin to warm up this weekend before a deep
upper trough dips southward out of eastern Canada and drops temperatures
again from the Northeast to Mid-Atlantic beginning early next week.

Kebede


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