Atmospheric Rivers

Short Range Forecast Discussion
NWS Weather Prediction Center College Park MD
Tue May 28 2024
Valid 12Z Tue May 28 2024 – 12Z Thu May 30 2024

…Numerous strong to severe thunderstorms and areas of flash flooding
likely across portions of northern and central Texas today…

…Unsettled weather with thunderstorms and heavy rain possible over the
northern Great Basin/Rockies today before shifting into the northern High
Plains on Wednesday…

…Sweltering heat continues across parts of South Texas and southern
Florida…

The Lone Star State will be the focus for active weather today as strong
thunderstorms develop along a southern High Plains dryline and lingering
stationary front. Ample atmospheric moisture content and instability will
support the likelihood of storms containing significant damaging wind
gusts and very large hail. Ongoing thunderstorms along the Red River
Valley of the South are expected to continue through the morning hours
before numerous additional storms form across western and north-central
Texas by the afternoon. Merging cells and clusters of storms are also
likely to contain intense rainfall rates capable of triggering several
flash floods, particularly for areas just west of Dallas-Fort Worth and
north of Austin. The threat of scattered flash flooding and severe
thunderstorms includes a much larger region extending from the Texas
Panhandle to the western Gulf Coast. For the overnight timeframe, heavy
rain and severe weather chances are forecast to gradually decrease and
slide eastward within Texas. Residents and visitors are reminded to remain
weather aware, have numerous ways to receive warnings and never drive
across flooded roadways.

A cold front progressing across the Northwest, northern Great Basin, and
northern Rockies today will provide enough forcing to produce the
potential for scattered severe thunderstorms capable of containing
damaging wind gusts for parts of northeast Oregon, northern/central Idaho,
and western Montana. A few storms may also produce heavy rain and isolated
flash flooding. This area of unsettled weather is expected to swing
eastward by midweek and enter the north-central High Plains before an
expanding area of storminess returns to the central/southern Plains on
Thursday.

Elsewhere, cold air advection on the southwestern periphery of an eastern
Canada low pressure system will produce scattered areas of showers and
storms over the next few days from the Great Lakes and Upper Midwest to
the Ohio Valley, Mid-Atlantic, and Northeast. A few storms could contain
hail and brief damaging winds today from southern Wisconsin to northern
Illinois and northwest Indiana.

The heat plaguing much of the Gulf Coast and southern Texas is finally
abating, but will linger across parts of southern Texas today with heat
indices up to 115 degrees. High temperatures are also expected to remain
above average and near daily record highs throughout the central and
southern Florida Peninsula over the next few days.

Short Range Forecast Discussion
NWS Weather Prediction Center College Park MD
Mon May 27 2024
Valid 12Z Mon May 27 2024 – 12Z Wed May 29 2024

…Severe thunderstorms and areas of heavy rain to impact much of the
eastern U.S., with isolated severe weather possible in the southern
Plains…

…Dangerous heat remains in place this Memorial Day throughout
southern/central Texas, the western and central Gulf Coast, as well as
southern Florida before some gradual relief by midweek…

…Unsettled weather and thunderstorms return to the southern Plains on
Tuesday, as well as the northern Great Basin and northern Rockies…

The severe weather threat shifts eastward today along a cold front
extending southward from a low pressure system forecast to slide northeast
over the Great Lakes. Ongoing storms stretching from the upper Ohio Valley
to the lower Mississippi Valley are expected to weaken this morning, but
redevelopment is likely this afternoon along and ahead of this boundary.
Clusters of merging thunderstorms are possible in the Mid-Atlantic and
Northeast, which may also contain intense rainfall rates. This heavy rain
could lead to scattered instances of flash flooding from northeast
Maryland to the Catskill Mountains of New York, where a Slight Risk (level
2/4) of Excessive Rainfall is in effect through tonight. The severe
weather threat includes a broader region extending from the lower Great
Lakes to the Southeast, with damaging wind gusts and hail the primary
hazards, with isolated tornadoes possible in the eastern Mid-Atlantic. As
the cold front extends westward towards the southern Plains, a few
isolated severe thunderstorms are also possible in parts of central and
eastern Texas.

South of the cold front in parts of Texas, the Gulf Coast, and southern
Florida, oppressive and dangerous heat continues today. Highs into the
upper 90s and triple digits are forecast throughout much of the Lone Star
State, with a few daily record highs possible. Elevated humidity levels
will lead to heat indices up to 120 degrees across portions of southern
Texas. Excessive Heat Warnings and Heat Advisories are in effect from
south-central Texas to the central Gulf Coast. Additionally, a simmering
Memorial Day is also in store for parts of the Florida Peninsula, where
daily record highs could be tied/broken in Key West, Port St Lucie, and
Melbourne. Summer heat is expected to linger over the Sunshine state
through midweek, while gradual cooling enters the Gulf Coast and Texas as
an approaching cold front inches towards the region. Residents are
reminded to follow proper heat safety and check on the vulnerable
population over at least the next few days.

The next round of active weather should return to the southern Plains on
Tuesday as scattered thunderstorms impact parts of southeast New Mexico
and much of Texas near a lingering stationary front. Severe wind gusts and
large hail are possible, as well as heavy rain producing scattered areas
of flash flooding. Meanwhile, a separate area of thunderstorms is possible
along a cold front as it progresses from the northern Great Basin on
Tuesday into the northern High Plains on Wednesday. Isolated thunderstorms
could turn severe and contain intense rainfall rates in these regions.

Short Range Forecast Discussion
NWS Weather Prediction Center College Park MD
Sun May 26 2024
Valid 12Z Sun May 26 2024 – 12Z Tue May 28 2024

…Severe weather and heavy rain chances shift into the Mid-Mississippi,
Ohio and Tennessee valleys today before progressing into the Mid-Atlantic,
Southeast, and Gulf Coast on Memorial Day…

…Dangerous and potentially record-breaking heat continues across parts
of Texas, the western Gulf Coast, and southern Florida…

…Active weather returns to the southern Plains on Tuesday with
additional chances for severe weather and flash flooding…

An organizing storm system over the central U.S. is responsible for
numerous thunderstorms stretching from Kansas/Missouri to the Edwards
Plateau of Texas. Boundaries aiding this convection include a dryline
extending southward through the southern Plains and a slowly lifting warm
front stretching from the central Plains through the Ohio Valley. Current
storms are expected to grow upscale and merge into a larger complex of
thunderstorms by morning while swinging through parts of Missouri,
Illinois, western Kentucky, and neighboring states. Damaging wind gusts,
large hail, and tornadoes are possible. Additionally, heavy rain may lead
to scattered instances of flash flooding with this initial burst of
thunderstorms. By the afternoon hours another round of showers and
thunderstorms are expected to develop along a cold front and impact
similar regions, with the severe threat shifting further east across the
Ohio Valley overnight. More chances for all modes of severe weather are
possible, with repeating storms potentially increasing the flash flooding
threat throughout parts of Kentucky and Tennessee. Area of heavy rain may
also lead to flash flooding concerns near the low pressure center as it
progresses toward southern Wisconsin tonight.

As the center of the storm system enters the Great Lakes on Monday and the
attached cold front extends from the Ohio Valley to the southern Plains,
severe weather and heavy rain chances will focus along the eastern U.S.
and Gulf Coast States. More specifically, the greatest chances for intense
rainfall rates leading to flash flooding exists across eastern
Pennsylvania and neighboring section of southeast New York and northwest
New Jersey, where a Slight Risk (level 2/4) of Excessive Rainfall is in
effect on Memorial Day. Severe thunderstorms are most likely across the
Mid-Atlantic as well as an area stretching from the Lower Mississippi
Valley to the Southeast. Damaging wind gusts and hail are the primary
potential hazards. Residents and visitors planning to enjoy outdoor
holiday barbecues and parties should remain weather aware and have
multiple ways to receive warnings.

Oppressive and potentially dangerous heat is set to continue for at least
the next few days throughout parts of southern Texas, the lower
Mississippi Valley, and southern Florida. Highs are expected to reach well
into the 90s for the southern Plains and western Gulf Coast, with triple
digits across southern portions of Texas. Elevated humidity levels will
make it feel even hotter, with heat indices approaching 115 degrees. Daily
record highs are also possible in this region and extending to southern
Florida as well through Tuesday. Residents and visitors are urged to
follow proper heat safety by staying hydrated, taking breaks inside
buildings with air conditioning, as well as checking on the vulnerable
population. Above average and summer-like temperatures will also extend
towards the eastern U.S. today as well before slightly cooler weather
arrives behind a cold front on Tuesday. Conversely, a warm up is on the
way throughout the West as upper ridging builds and spreads highs into the
70s and 80s for the northern Great Basin and northern High Plains.

Meanwhile, the next round of active weather is set to impact the southern
Plains on Tuesday as a lingering frontal boundary and favorable upper jet
dynamics spark developing thunderstorms from western Oklahoma/Kansas to
Texas and the lower Mississippi Valley. Scattered instances of flash
flooding are possible, which is highlighted by a Slight Risk of Excessive
Rainfall throughout central and north-central Texas, as well as southern
Oklahoma. Some storms in the southern High Plains may also become strong
enough to produce damaging wind gusts and large hail.

Short Range Forecast Discussion
NWS Weather Prediction Center College Park MD
Sat May 25 2024
Valid 12Z Sat May 25 2024 – 12Z Mon May 27 2024

…Dangerous severe weather threat forecast across parts of the
central/southern Plains through tonight before the potential for strong
storms shift to the mid-Mississippi and Ohio valleys on Sunday…

…Extreme fire weather expected for south-central New Mexico with
critical fire weather throughout much of the southern Rockies/High Plains
today…

…Simmering heat continues across South Texas, the Gulf Coast, and
southern Florida through Memorial Day…

The start of this Memorial Day weekend will feature yet another round of
severe weather impacting the central United States as the next storm
system strengthens across the central Plains. A textbook Great Plains
severe weather setup is expected as a warm front lifts to the central
Plains and middle Mississippi Valley while a sharp dryline extends south
of the low into the southern Plains. Discrete supercells are anticipated
to develop this evening in response to an ejecting shortwave out of the
Rockies as aforementioned surface boundaries provide a focus for
developing thunderstorms. A few supercells may be capable of intense
tornadoes, with giant hail and destructive winds also expected. By
tonight, thunderstorms are expected to merge into clusters and potentially
bow echos as they push eastward towards the Ozarks. The Storm Prediction
Center has issued a Moderate Risk (level 4/5) for severe thunderstorms in
parts of Kansas, Oklahoma, and far southwest Missouri. Additionally,
storms are expected to contain intense rainfall rates that could lead to
scattered instances of flash flooding from the central/southern Plains to
the mid-Mississippi Valley into tonight. The low pressure system and
associated storminess are expected to shift eastward on Sunday into
portions of the Midwest and Ohio Valley. Damaging wind gusts are the most
likely hazards as a complex of thunderstorms progress from Missouri to
Kentucky, as well as the possibility of flash flooding, hail, and a few
tornadoes. The Memorial Day finale for this spring storm system will
impact the eastern U.S. on Monday as low pressure swings into the Great
Lakes and a strong cold front extends along the Appalachians. Showers and
storms may dampen outdoor barbecues, while also containing frequent
lighting, have rain, and gusty winds. Residents and visitors should remain
weather aware this holiday weekend and have multiple ways of receiving
warnings.

West of the dryline today throughout the southern High Plains and southern
Rockies will exist extremely critical fire weather conditions. Low
relative humidity, gusty winds, and dry vegetation could lead to any newly
formed fires to spread rapidly. Red Flag Warnings span throughout all of
New Mexico, southeast Arizona, western Texas, and the western Oklahoma
Panhandle.

The temperature outlook for this weekend includes above average
temperatures leading to a summer-like feel for much of the eastern U.S.,
Mid-South, and central/southern Plains as heat also begins to build back
into the West by Memorial Day. Cooler temperatures are forecast to remain
over the Rockies, Northwest, and north-central United States. Heat will
reach oppressive levels across South Texas, the Gulf Coast, and southern
Florida, with heat indices into the triple digits and the potential for
daily record highs. Excessive Heat Warnings remain in effect across South
Texas due to heat indices rising to around 115 degrees, which could be
dangerous for those spending extended amounts of time outdoors.

Short Range Forecast Discussion
NWS Weather Prediction Center College Park MD
Fri May 24 2024
Valid 12Z Fri May 24 2024 – 12Z Sun May 26 2024

…Heavy rain and severe thunderstorm chances extend from the Midwest to
the southern Plains today…

…Next round of severe weather to develop across the central/southern
Plains Saturday evening before shifting into parts of the mid-Mississippi
and Ohio valleys on Sunday…

…Dangerous and potentially record-breaking heat continues across South
Texas, the Gulf Coast, and southern Florida through Memorial Day weekend…

The relentlessly active spring weather pattern is set to continue through
the holiday weekend as two separate systems are anticipated to be
responsible for numerous showers and thunderstorms across the middle of
the Nation. An initial low pressure system deepening over the northern
Plains today, while an attached cold front extends from the Upper Midwest
to the Southern Plains, should maintain a focus for showers and
thunderstorms to develop. Additionally, cold air aloft on the backside of
the strong system could allow for snow to mix with rain across parts of
North Dakota. Along the cold front as it extends southward, storms could
turn severe from the Midwest to the southern Plains, with the greatest
potential for tornadoes across central to northern Illinois, far eastern
Iowa, and southern Wisconsin. This same cold front could slow it’s forward
progress and allow for thunderstorms to potentially train across parts of
southern Arkansas, northern Louisiana, and northeast Texas, leading to the
threat of scattered flash flooding. Elsewhere, scattered thunderstorms may
dampen outdoors plans throughout the Southeast and Tennessee Valley.

The next shortwave to eject out of the western U.S. and into the Great
Plains is expected to spark the next round of severe weather late on
Saturday in the central/southern Plains. At the surface, low pressure
forming in the lee of the central Rockies is forecast to lift a warm front
northward to the central Plains and mid-Mississippi Valley, while a sharp
dryline extends southward into the southern Plains. These features
combined with a strengthening low-level jet will allow for storms to turn
severe, containing a risk for large hail, intense rainfall rates, a few
tornadoes, and damaging wind gusts. The Storm Prediction Center has issued
an Enhanced Risk (level 3/5) for severe thunderstorms across parts of
Kansas, Oklahoma, and western Missouri in order to highlight the threat.
As clusters of storms move eastward with the system on Sunday, the flash
flooding and severe weather will shift to the mid-Mississippi and Ohio
valleys. Tornadoes, hail, strong winds, and flash flooding will be
possible. Residents and visitors located within the threat for severe
weather this weekend are urged to have multiple ways of receiving warnings
and to continue to check for the latest forecast.

Elsewhere, heat remains the main weather story along the Gulf Coast, South
Texas, and southern Florida. The hottest locations are forecast throughout
South Texas into late this weekend as highs soar above the century mark,
with heat indices up to 120 degrees possible. Temperatures into the upper
90s are anticipated to spread into much of Texas on Saturday and Sunday as
well. High heat indices will also impact the immediate Gulf Coast region
and South Florida, while also potentially breaking a few record high
temperatures. Warm overnight conditions will also provide little to no
relief for those without adequate or reliable cooling.

Short Range Forecast Discussion
NWS Weather Prediction Center College Park MD
Thu May 23 2024
Valid 12Z Thu May 23 2024 – 12Z Sat May 25 2024

…Heavy rain and severe weather threats across the Arklatex region today
will expand northward across the northern and central Plains tonight…

…Heavy rain and severe weather threats will shift east into the Midwest
and remain across the Arklatex region on Friday…

…Heavy snow expected today across the higher elevations of the northern
Rockies…

As a low pressure system continues to move further away from the Great
Lakes into southeastern Canada, showers and thunderstorms ahead of the
associated cold front will push farther eastward across New England and
the Mid-Atlantic states today. Meanwhile, the trailing portion of the
front will become nearly stationary across the Mid-South where the focus
of heavy rain and severe thunderstorms will be the greatest today. These
thunderstorms may reform across the Arklatex region as the frontal
boundary meanders in the vicinity, along with the arrival of some
additional lifting mechanisms from an upper-level jet stream from the
west-southwest. The jet stream winds will tend to carry the showers and
storms downstream across the Mid-South toward the Appalachians and the
Mid-Atlantic states, keeping the weather unsettled for these areas through
the next couple of days with modest rainfall amounts although locally
heavy rain can be expected in some of the embedded thunderstorms.

Meanwhile, a rather deep and compact upper-level low from Alaska a couple
of days ago is now sweeping across the northwestern U.S. This system will
continue to usher a cold air mass through the western U.S. with a round of
heavy wet snow across the higher-elevations of Idaho, western Montana, and
into northwestern/northern Wyoming today. The energy from this system
will help develop another low pressure system across the northern and
central High Plains today. The low pressure system is forecast to further
intensify on Friday as the upper low exits into northern Plains and begins
to lift toward the northeast. Another round of showers and possibly
severe thunderstorms will develop and expand across many locations up and
down the Great Plains later today, and will begin to lift east and
northeastward into the Midwest, and along the Mississippi Valley on
Friday. A swath of cold rain is forecast across North Dakota,
southeastern Montana, and into northwestern Minnesota as the low pressure
center tracks just to the south. Temperatures could be cold enough for
some wet snow to mix in with the rain later tonight near the Canadian
border. Increasingly strong and gusty winds will also add to the chill as
the low pressure system intensifies and wraps the precipitation around the
center of circulation. By Saturday morning, the showers and storms should
progress into the Great Lakes and down across the Midwest ahead of and
near the cold/occluded fronts. Meanwhile, scattered showers and storms
will linger across the Mid-South into the Southeast where the old front
lingers.

Across southern Texas an early-season heat wave is forecast to gradually
intensify through the next few days into the Memorial Day weekend. Record
or near-record warm overnight temperatures will provide little to no
relief to those without adequate or reliable cooling. By this weekend,
record daily high temperatures and heat index readings over 115 degrees in
South Texas will also be possible. Check local media and government
websites for cooling center locations and hours, especially if you
encounter or are dealing with a loss of power. If you use a portable
generator, do so safely to avoid carbon monoxide poisoning. Never use a
generator inside a house, garage, or other enclosed space! Finally, a
critical fire danger is forecast for the southern Rockies into the
southern High Plains per the Storm Prediction Center.