Short Range Forecast Discussion
NWS Weather Prediction Center College Park MD
400 AM EDT Wed Jul 16 2025
Valid 12Z Wed Jul 16 2025 - 12Z Fri Jul 18 2025
...Heavy rainfall and flash flood threat continues for portions of the
Mid-Atlantic west into the Ohio Valley Wednesday...
...Heavy downpours and flash flooding expected with a tropical disturbance
moving along the north-central Gulf Coast through mid-week...
...Potent summer storm system to bring flash flooding and severe weather
threat to the Midwest and northern/central Plains Wednesday...
...Heat threat building across much of the eastern U.S. through at least
mid-week...
A moisture-rich Summer-time airmass continues to dominate much of the
eastern and central U.S. through midweek, supporting multiple regions of
scattered to widespread thunderstorms capable of producing heavy downpours
and flash flooding. The Mid-Atlantic and vicinity remain one of these
regions as a decaying frontal boundary and the approach of a second cold
front from the north provide the focus for a renewed round of
thunderstorms Wednesday. Plentiful moisture near climatological maximums
will fuel efficient, very heavy downpours, with a Slight Risk of Excessive
Rainfall (level 2/4) in effect covering the central
Mid-Atlantic/Appalachians west into the Upper Ohio Valley and Lower Great
Lakes, where scattered instances of flash flooding are expected. Storms
will continue ahead of the cold front across the interior
Northeast/northern Mid-Atlantic/Upper Ohio Valley Thursday. To the south,
the National Hurricane Center continues to monitor an area of low pressure
over the Florida Panhandle that may reemerge into the northern Gulf as it
slowly drifts westward. Regardless of any further development, continued
thunderstorm development around the low and plentiful Gulf moisture will
bring the threat for flash flooding. A more isolated risk is expected
Tuesday along the Florida Gulf coast west through the central Gulf Coast.
The threat increases for more scattered flash flooding Wednesday as the
low approaches the central Gulf Coast, with a Slight Risk in effect, and a
Moderate Risk (level 3/4) is in place for Thursday.
A potent Summer storm system moving through the central U.S. will be
another focus area for more widespread thunderstorms with the threat of
both flash flooding and severe weather. A complex convective scenario will
unfold Wednesday as ongoing overnight thunderstorm complexes along a cold
front stretching from the Upper Midwest southwest through the Missouri
Valley and into the central Plains will help influence further
thunderstorm development into the day. The ongoing complexes may continue
with renewed/expanded development with daytime heating, while remnant
outflows reinforce the cold front/effective boundary and provide a focus
area for additional renewed development. This currently appears most
likely in two corridors: first, from the Upper Mississippi Valley east
into the Great Lakes, and second, from the central Plains east into the
Middle Missouri and Mississippi Valleys. Slight Risks of Excessive
Rainfall are in effect for the threat of scattered flash flooding. In
addition, the Storm Prediction Center has included a Slight Risk of severe
weather (level 2/5) for the Upper Mississippi Valley to Great Lakes for
the threat of damaging winds with the re-intensifying/redeveloping
thunderstorms, as well as along the central High Plains of Colorado where
damaging winds and large hail can be expected as afternoon thunderstorms
develop in moist post-frontal upslope flow. The front will push southward
on Sunday, with scattered thunderstorms expected along its length from the
Ohio/Middle Mississippi Valleys west through the central Plains with the
potential of isolated flash flooding. A locally higher threat for flash
flooding is expected for portions of the central/southern High Plains
where more widespread storms are expected along the tail end of the front
pushing up against the Rockies, with a Slight Risk in effect. Further
west, Monsoonal moisture will continue to lead to scattered thunderstorms
for portions of the Southwest/Four Corners region the next couple of days,
with isolated flash flooding possible, particularly for terrain sensitive
areas and burn scars.
Increasingly uncomfortable and potentially dangerous heat is expected
across the eastern U.S. west to the Lower Mississippi Valley the next
couple of days as temperatures rise into the 90s and the moisture-rich,
muggy airmass remains. Widespread Moderate to Major Heat Risk (levels
2-3/4) is in place indicating a level of heat dangerous to anyone without
access to air conditioning or adequate hydration. A cold front will bring
some relatively cooler temperatures to the interior Northeast Thursday.
Temperatures will also remain uncomfortably hot across the Pacific
Northwest Wednesday as highs climb into the 90s, with heat-related
advisories in effect. An approaching upper-level system/cold front will
bring relatively cooler conditions Thursday as highs drop into the upper
mid- to upper 80s. The rest of the Interior West can expect average to
above average hot Summer-time conditions. The Storm Prediction Center has
included an Elevated to Critical Risk of Fire Weather (levels 1-2/3)
across portions of the central Great Basin given the hot temperatures and
the potential for dry thunderstorms with lightning/gusty winds. Conditions
remain below average across the Desert Southwest with Monsoonal moisture
in place, and cool along the Pacific Coast under the influence of onshore
flow. The potent cold front pushing through the northern/central Plains
and Midwest has brought early Fall-like conditions, as highs mainly in the
60s to 70s are upwards of 25-35 degrees below average and near record low
maximums for many locations. Forecast lows are in the 40s for much of the
northern Plains Thursday morning. Temperatures will be near average in the
Southern Plains, with mainly 90s expected.
Putnam
Graphics available at
https://www.wpc.ncep.noaa.gov/basicwx/basicwx_ndfd.php