Short Range Forecast Discussion
NWS Weather Prediction Center College Park MD
349 PM EDT Wed Apr 17 2019
Valid 00Z Thu Apr 18 2019 - 00Z Sat Apr 20 2019
...Strong storm to impact the central to southern U.S. with severe
thunderstorms and flash flooding expected through Thursday...
...Heavy rain and the possibility of severe thunderstorms shifts to the
eastern U.S. by Friday...
Several locations will see a threat for severe thunderstorms through the
remainder of the day as a two-part upper level storm system moves into the
Great Plains. A northern portion will track through the Northern Plains
this afternoon and into the Upper Mississippi Valley by Thursday morning.
A surface low and its corresponding cold/warm fronts will track ahead of
this feature into Iowa and Wisconsin through tonight with increasing
low-level moisture transporting northward through the Mississippi River
Valley. The Storm Prediction Center (SPC) has a Slight Risk for severe
storms surrounding the tri-state region of Iowa/Wisconsin/Illinois with
concerns over tornadoes and hail. Heavy rain could also cause localized
flooding in these areas.
Farther to the south, the southern portion of the upper level storm system
is moving across New Mexico into the Texas Panhandle this afternoon, with
thunderstorms erupting near the cold front stretching southwestward from
the surface low in Iowa to the Texas Panhandle this evening. It is here,
from the northern Texas Panhandle into southeastern Kansas where an
Enhanced Risk is in place by SPC. Another Enhanced Risk area extends
southward from southeast Oklahoma into northern and central Texas for
severe thunderstorms forecast to develop late this evening and overnight.
These storms will also pose a flash flood threat through Thursday morning
from eastern Texas into the ArkLaTex toward the Memphis metropolitan area.
Over the past week, some of these same locations across the South have
seen well above average rainfall and may be at a greater risk of flash
flooding from additional heavy rain.
Thursday will be much quieter, but significantly colder behind the storm
system from the north-central U.S. border with Canada to the Rio Grande.
Forecast high temperatures are only in the 50s to 60s for many. The severe
weather and flash flood threat will shift east ahead of the cold front
from the Illinois/Indiana border to the central Gulf Coast, with a greater
severe threat (Enhanced Risk by SPC) in place from central Louisiana to
western Alabama and the Florida Panhandle. Late spring-like temperatures
will also shift east for Thursday with highs in the 70s to low 80s as far
north as northern Ohio and western New York.
By Friday the heavy rain and severe weather threat again shifts east, this
time into the eastern U.S. SPC has an Enhanced Risk for severe
thunderstorms across the eastern Carolinas and southeastern Virginia.
Flash flooding will also become a possibility across the mid-Atlantic and
parts of the Northeast as strong southerly winds increase moisture and
cause multiple rounds of heavy rain roll across the region. Meanwhile, a
separate system will enter the Northwest and bring unsettled weather from
Washington and Oregon into the Northern Rockies.
Graphics available at www.wpc.ncep.noaa.gov/basicwx/basicwx_ndfd.php