SPC Severe Thunderstorm Watch 530

Source: US National Oceanic and Atmospheric Administration

Note:  The expiration time in the watch graphic is amended if the watch is replaced, cancelled or extended.Note: Click for Watch Status Reports.
SEL0

URGENT – IMMEDIATE BROADCAST REQUESTED
Severe Thunderstorm Watch Number 530
NWS Storm Prediction Center Norman OK
955 PM CDT Sat Oct 23 2021

The NWS Storm Prediction Center has issued a

* Severe Thunderstorm Watch for portions of
Southern Iowa
Northeast Kansas
Northern Missouri
Southeast Nebraska

* Effective this Saturday night and Sunday morning from 955 PM
until 500 AM CDT.

* Primary threats include…
Scattered large hail events to 1.5 inches in diameter likely

SUMMARY…Thunderstorms will continue to develop across northeast
Kansas and much of northern Missouri into southeast Nebraska and
southern Iowa late this evening into the overnight. The strongest
storms will be capable of large hail.

The severe thunderstorm watch area is approximately along and 60
statute miles north and south of a line from Beatrice NE to 15 miles
east southeast of Kirksville MO. For a complete depiction of the
watch see the associated watch outline update (WOUS64 KWNS WOU0).

PRECAUTIONARY/PREPAREDNESS ACTIONS…

REMEMBER…A Severe Thunderstorm Watch means conditions are
favorable for severe thunderstorms in and close to the watch area.
Persons in these areas should be on the lookout for threatening
weather conditions and listen for later statements and possible
warnings. Severe thunderstorms can and occasionally do produce
tornadoes.

&&

AVIATION…A few severe thunderstorms with hail surface and aloft to
1.5 inches. Extreme turbulence and surface wind gusts to 50 knots. A
few cumulonimbi with maximum tops to 450. Mean storm motion vector
24030.

…Guyer

Note: The Aviation Watch (SAW) product is an approximation to the watch area. The actual watch is depicted by the shaded areas.
SAW0
WW 530 SEVERE TSTM IA KS MO NE 240255Z – 241000Z
AXIS..60 STATUTE MILES NORTH AND SOUTH OF LINE..
BIE/BEATRICE NE/ – 15ESE IRK/KIRKSVILLE MO/
..AVIATION COORDS.. 50NM N/S /25WNW PWE – 16ESE IRK/
HAIL SURFACE AND ALOFT..1.5 INCHES. WIND GUSTS..50 KNOTS.
MAX TOPS TO 450. MEAN STORM MOTION VECTOR 24030.

LAT…LON 41169675 40889229 39159229 39419675

THIS IS AN APPROXIMATION TO THE WATCH AREA. FOR A
COMPLETE DEPICTION OF THE WATCH SEE WOUS64 KWNS
FOR WOU0.

Watch 530 Status Report Message has not been issued yet.

Note:  Click for Complete Product Text.TornadoesProbability of 2 or more tornadoes

Low (

SPC Severe Thunderstorm Watch 530 Status Reports

Source: US National Oceanic and Atmospheric Administration

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Watch 530 Status Reports

Watch 530 Status Message has not been issued yet.

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NOAA / National Weather ServiceNational Centers for Environmental PredictionStorm Prediction Center120 David L. Boren Blvd.Norman, OK 73072 U.S.A.spc.feedback@noaa.govPage last modified: October 24, 2021
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SPC Oct 24, 2021 0100 UTC Day 1 Convective Outlook

Source: US National Oceanic and Atmospheric Administration

 For best viewing experience, please enable browser JavaScript support.

Oct 24, 2021 0100 UTC Day 1 Convective Outlook
Updated: Sun Oct 24 00:47:25 UTC 2021 (Print Version |   |  )
Probabilistic to Categorical Outlook Conversion Table

 Forecast Discussion

SPC AC 240047

Day 1 Convective Outlook
NWS Storm Prediction Center Norman OK
0747 PM CDT Sat Oct 23 2021

Valid 240100Z – 241200Z

…THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS FROM THE CENTRAL
PLAINS THROUGH LOWER MISSOURI VALLEY…

…SUMMARY…
Large hail is expected with thunderstorms late tonight across
portions of the central Plains and Lower Missouri Valley region.

…01Z Update…

…Northeast KS/Southeast NE/Far Southwest IA/Northern MO…
Recent surface analysis places a low near DDC, with a warm front
extending east-northeastward from this low across southern KS.
Additionally, area VAD profiles and SPC mesoanalysis continue to
show increasing low-level flow throughout the warm sector to the
south of this warm front. This low-level flow is expected to
continue strengthening as the surface low slowly moves
northeastward. Persistent warm-air advection along this frontal zone
will promote the development of elevated thunderstorms in an arc
from the eastern KS/NE border vicinity eastward across northern MO.
Mid-level lapse rates (sampled well by the 00Z TOP sounding) are
expected to steep enough to support moderate buoyancy and robust
persistent updrafts. Effective bulk shear of 40-50 kt and modest
hodograph curvature within the storm inflow layer will support the
potential for embedded/elevated supercells capable of producing
occasional large hail tonight.

…Far East-Central TX Panhandle/Far Western OK…
Lone supercell in Wheeler and Collingsworth Counties in the far
east-central TX Panhandle may persist for the hour or so before
nocturnal stabilization leads to weakening. Until then, isolated
hail and/or an isolated damaging wind gust may occur.

..Mosier.. 10/24/2021

CLICK TO GET WUUS01 PTSDY1 PRODUCT

.html”>Latest Day 2 Outlook/Today’s Outlooks/Forecast Products/Home

Introducing NCEI’s Regional Climate Services Directors

Source: US National Oceanographic Data Center

NCEI is excited to introduce its full slate of six permanent Regional Climate Services Directors (RCSDs) who are committed to serving the Alaska, Central, Eastern, Pacific, Southern, and Western regions, encompassing the entire United States and its territories. The RCSDs are an integral part of NCEI’s local, regional, national, international, sectoral, and topical engagement.

RCSDs are key to increasing the value of climate information to users across the United States and its territories and helping meet a wide range of local needs for environmental information and services. They support efficient and cost-effective delivery of information and services while also sharing pertinent scientific data and information to facilitate informed decisions about climate issues that concern each region.

The RCSDs work directly with partners and constituent groups in public and private sectors to understand their climate information needs, to translate existing information, and to interpret those needs for building and improving climate tools and resources. These partners include NOAA’s climate services entities such as the Regional Climate Centers (RCCs), Regional Integrated Sciences and Assessments (RISA) program, state climatologists, and the National Integrated Drought Information System (NIDIS), in addition to an array of other agencies, institutions, and organizations. The RCSDs also work with front-line communities like indigenous people and tribes and underserved communities. RCSDs help customers understand and apply information to mitigate negative climate impacts and find ways to use NCEI and NOAA’s environmental data products and services to their advantage.

NCEI’s Regional Climate Services Directors

The six RCSDs ensure the U.S. and its territories receive valuable, region-specific climate-related support and service.

Get to know more about each of the RCSDs, by region:

Alaska Region: Jessica Cherry

Jessica Cherry is NCEI’s Regional Climate Services Director for the Alaska Region. She grew up in Lincoln, Nebraska, and then spent ten years in New York City earning a BA in Economics and Earth/Environmental Science, an MA in Physical Oceanography, and a PhD in Climate Science and Hydrology at Columbia University. In 2006, she moved to Fairbanks, AK, where she went on to lead a research group in hydroclimatology and airborne remote sensing at the University of Alaska.

In 2017, she started her Federal career with NOAA as a senior hydrologist at the Alaska-Pacific River Forecast Center. There, she served as the Climate Focal point, snow and remote sensing expert, and lead of an Uncrewed Aerial Systems project. Jessie is also a commercial airplane pilot, both land and sea, and was a top-100 finalist for the NASA Astronaut Corps in 2012 and 2016. In her spare time, she enjoys hiking with her husband Bob, reading, writing, gardening, and flying her Cessna 182.

Central Region: Doug Kluck

Doug Kluck is NCEI’s Climate Services Director for the Central Region. Doug works across 14 states from the Great Lakes to the Rocky Mountains. He has worked with NOAA since 1992, first with the National Weather Service as a weather and river forecaster, then as a regional hydrologist and climatologist.

Doug’s responsibilities include coordination and collaboration among regional climate entities. This involves interpretation and translation of technical climate information for all levels of government as well as private and institutional interests. Doug is a Tribal liaison for NOAA, and he serves as the Coordinating Lead Author for the Northern Plains Chapter of the Fifth National Climate Assessment. Doug works closely with a number of partners before, during, and after extreme climate events to ensure accurate information response and assessment with core partners in the region.

The Central Region encompasses North Dakota, South Dakota, Wyoming, Colorado, Nebraska, Kansas, Minnesota, Iowa, Missouri, Wisconsin, Illinois, Michigan, Indiana, and Kentucky.

Eastern Region: Ellen Mecray

Ellen Mecray is NCEI’s Regional Climate Services Director for the Eastern Region. She focuses on the delivery and interpretation of climate information using networks across several critical economic sectors including health, fisheries, transportation, agriculture, and energy. Ellen is a federal leader for climate services in the region, working to coordinate and collaborate with partners to deliver climate services across federal, state, private, and institutional groups.

In addition to providing climate expertise for her 16-state region, she also serves as the Coordinating Lead Author for the Northeast regional chapter of the Fifth National Climate Assessment, and is a leader for several federal interagency partnerships. Recently, Ellen has applied her interdisciplinary systems-level science to a model for service delivery to state and local decision-makers. 

The Eastern Region encompasses Maine, New Hampshire, Vermont, Massachusetts, Rhode Island, Connecticut, New York, New Jersey, Delaware, Pennsylvania, Maryland, Ohio, West Virginia, Virginia, North Carolina, and South Carolina.

Southern Region: Sharon Mesick

Sharon Mesick is NCEI’s Regional Climate Services Director for the Southern Region. Her focus is on strengthening partnerships through development and delivery of a wide range of environmental and social science products and services, particularly those in the blue economy sector. Sharon is recognized as a tireless advocate for unfettered public access to environmental data. She was a member of NOAA’s Silver Medal award-winning Hurricane Katrina response team and was recognized for her active participation in NOAA’s response to the Deepwater Horizon oil spill incident.

Her previous work has included the duties as the chief of the NCEI Oceanographic and Geophysical Information Services Branch, the NCEI Coastal Data Development program manager, and as a NOAA Regional Ecosystem program manager. Prior to joining NOAA, Sharon worked in private industry where she specialized in environmental data analysis for the Naval Oceanographic Office.

The Southern Region encompasses New Mexico, Texas, Oklahoma, Arkansas, Louisiana, Mississippi, Georgia, Tennessee, Alabama, Florida, Puerto Rico, and the U.S. Virgin Islands.

Pacific Region: John Marra

John J. Marra is NCEI’s Regional Climate Services Director for the Pacific Region. He also sits as an adjunct senior fellow at the East–West Center. For nearly 30 years he has been working to connect science providers with science users, bridging the gap between data and information products to address issues related to natural hazards risk reduction and climate adaptation planning.

Throughout his career, he has directed particular attention toward the development and dissemination of data and products related to coastal flooding and erosion. 

The Pacific Region encompasses Hawaii, Guam, and the U.S. affiliated Pacific Islands.

Western Region: Joseph Casola

Joe Casola has been selected as NCEI’s Regional Climate Services Director for the Western region and will begin his position January 3, 2022. Joe has focused his career on translating information about climate variability, climate change, and climate impacts for policy makers, resource managers, and business leaders. He currently serves as an instructor for the Masters of the Environment Program at University of Colorado Boulder. His past positions include: deputy director at University of Washington’s Climate Impacts Group; staff scientist and program director for Science and Impacts at the Center for Climate and Energy Solutions; senior associate at ICF International; and post-doctoral fellow at the National Research Council.

Recent accomplishments include coordinating the Northwest Climate Conference, assisting the Department of Energy with the formation of the Partnership for Energy Sector Climate Resilience, and authoring the report Unfair Share: Exploring the Disproportionate Risks from Climate Change Facing Washington State Communities. Dr. Casola earned his PhD and MS degrees in Atmospheric Sciences from the University of Washington, and a BS in Chemistry from Duke University.

The Western Region encompassesArizona, California, Idaho, Montana, Nevada, Oregon, Utah, and Washington.

NCEI Regional Climate Services

The RCSDs are part of Regional Climate Services coordinated by NCEI. Services to the public are provided in cooperation with the RCSDs and six RCCs, led separately at the local level. Both RCSDs and RCCs spearhead regional information sharing and joint projects.

SPC – No watches are valid as of Sat Oct 16 23:02:02 UTC 2021

Source: US National Oceanic and Atmospheric Administration

Current Convective Watches (View What is a Watch? clip)Updated:  Sat Oct 16 23:15:09 UTC 2021 No watches are currently valid

Archived Convective WatchesTo view convective weather watches for a previous day, type in the date you wish to retrieve (e.g. 20040529 for May 29, 2004). Data available since January 1, 2004.

SPC Oct 16, 2021 2000 UTC Day 1 Convective Outlook

Source: US National Oceanic and Atmospheric Administration

SPC AC 161933

Day 1 Convective Outlook
NWS Storm Prediction Center Norman OK
0233 PM CDT Sat Oct 16 2021

Valid 162000Z – 171200Z

…THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS FROM VERMONT
SOUTHWARD INTO NEW JERSEY AND VICINITY…

…SUMMARY…
A few severe storms remain possible across parts of the Northeast
States through early evening.

…Northeast and Mid Atlantic…
A line of storms continues to move rapidly east across VT, curling
southwestward into southern NY and eastern PA. Northern parts of the
line have shown relative strength, with MLCAPE to 500 J/kg, cooler
temperatures aloft and stronger/backed 850 mb winds to 50 kt. A risk
of damaging gusts or a QLCS tornado may persist for a few more hours
as the low-topped convective line traverses the instability plume,
and before the boundary layer begins to cool.

For more information see mesoscale discussion 1873.

..Jewell.. 10/16/2021

.PREV DISCUSSION… /ISSUED 1040 AM CDT Sat Oct 16 2021/

…Northeast…
A high-shear/low-CAPE convective episode is expected to peak later
this afternoon. A swath of frontal precip, predominately stratiform
with embedded higher-reflectivity cores and sporadic lightning
flashes, is ongoing from northern NY southwest through central PA.
Some breaks in downstream cloud coverage should result in somewhat
more robust heating across the eastern PA/NJ area south. However,
buoyancy in this regime will remain meager owing to weak mid-level
lapse rates. Farther north, where deep-layer ascent will be
stronger, greater boundary-layer heating will likely be confined to
a corridor along the Upper Hudson to Champlain Valleys. This latter
region should coincide with amplification of 850-700 mb wind field
this afternoon, where enlarged low-level hodographs will foster an
embedded tornado risk for a brief period later this afternoon.
Otherwise, a thin, low-topped QLCS is expected to evolve
east-northeastward offering a threat for scattered damaging winds
from strong to locally severe gusts. These threats should wane after
dusk as convection spreads across New England.

CLICK TO GET WUUS01 PTSDY1 PRODUCT

NOTE: THE NEXT DAY 1 OUTLOOK IS SCHEDULED BY 0100Z

SPC Severe Thunderstorm Watch 529

Source: US National Oceanic and Atmospheric Administration

Note:  The expiration time in the watch graphic is amended if the watch is replaced, cancelled or extended.Note: Click for Watch Status Reports.
SEL9

URGENT – IMMEDIATE BROADCAST REQUESTED
Severe Thunderstorm Watch Number 529
NWS Storm Prediction Center Norman OK
1235 PM EDT Sat Oct 16 2021

The NWS Storm Prediction Center has issued a

* Severe Thunderstorm Watch for portions of
Far western Connecticut
Far western Massachusetts
Eastern New York
Northeast Pennsylvania
Vermont

* Effective this Saturday afternoon and evening from 1235 PM
until 700 PM EDT.

* Primary threats include…
Scattered damaging winds and isolated significant gusts to 75
mph possible
A tornado or two possible

SUMMARY…A thin, low-topped convective line should intensify as it
spreads east across eastern New York into western New England, as
well as possibly across northeast Pennsylvania. A brief tornado
threat is anticipated across parts of the Champlain and Upper Hudson
Valleys.

The severe thunderstorm watch area is approximately along and 55
statute miles east and west of a line from 35 miles north northwest
of Burlington VT to 30 miles south southwest of Monticello NY. For a
complete depiction of the watch see the associated watch outline
update (WOUS64 KWNS WOU9).

PRECAUTIONARY/PREPAREDNESS ACTIONS…

REMEMBER…A Severe Thunderstorm Watch means conditions are
favorable for severe thunderstorms in and close to the watch area.
Persons in these areas should be on the lookout for threatening
weather conditions and listen for later statements and possible
warnings. Severe thunderstorms can and occasionally do produce
tornadoes.

&&

AVIATION…A few severe thunderstorms with hail surface and aloft to
1 inch. Extreme turbulence and surface wind gusts to 65 knots. A few
cumulonimbi with maximum tops to 350. Mean storm motion vector
24045.

…Grams

SEL9

URGENT – IMMEDIATE BROADCAST REQUESTED
Severe Thunderstorm Watch Number 529
NWS Storm Prediction Center Norman OK
1235 PM EDT Sat Oct 16 2021

The NWS Storm Prediction Center has issued a

* Severe Thunderstorm Watch for portions of
Far western Connecticut
Far western Massachusetts
Eastern New York
Northeast Pennsylvania
Vermont

* Effective this Saturday afternoon and evening from 1235 PM
until 700 PM EDT.

* Primary threats include…
Scattered damaging winds and isolated significant gusts to 75
mph possible
A tornado or two possible

SUMMARY…A thin, low-topped convective line should intensify as it
spreads east across eastern New York into western New England, as
well as possibly across northeast Pennsylvania. A brief tornado
threat is anticipated across parts of the Champlain and Upper Hudson
Valleys.

The severe thunderstorm watch area is approximately along and 55
statute miles east and west of a line from 35 miles north northwest
of Burlington VT to 30 miles south southwest of Monticello NY. For a
complete depiction of the watch see the associated watch outline
update (WOUS64 KWNS WOU9).

PRECAUTIONARY/PREPAREDNESS ACTIONS…

REMEMBER…A Severe Thunderstorm Watch means conditions are
favorable for severe thunderstorms in and close to the watch area.
Persons in these areas should be on the lookout for threatening
weather conditions and listen for later statements and possible
warnings. Severe thunderstorms can and occasionally do produce
tornadoes.

&&

AVIATION…A few severe thunderstorms with hail surface and aloft to
1 inch. Extreme turbulence and surface wind gusts to 65 knots. A few
cumulonimbi with maximum tops to 350. Mean storm motion vector
24045.

…Grams

Note: The Aviation Watch (SAW) product is an approximation to the watch area. The actual watch is depicted by the shaded areas.
SAW9
WW 529 SEVERE TSTM CT MA NY PA VT 161635Z – 162300Z
AXIS..55 STATUTE MILES EAST AND WEST OF LINE..
35NNW BTV/BURLINGTON VT/ – 30SSW MSV/MONTICELLO NY/
..AVIATION COORDS.. 50NM E/W /15NNE PLB – 26WNW SAX/
HAIL SURFACE AND ALOFT..1 INCH. WIND GUSTS..65 KNOTS.
MAX TOPS TO 350. MEAN STORM MOTION VECTOR 24045.

LAT…LON 44937230 41297396 41297608 44937455

THIS IS AN APPROXIMATION TO THE WATCH AREA. FOR A
COMPLETE DEPICTION OF THE WATCH SEE WOUS64 KWNS
FOR WOU9.

Watch 529 Status Report Message has not been issued yet.

Note:  Click for Complete Product Text.TornadoesProbability of 2 or more tornadoes

Low (20%)

Probability of 1 or more strong (EF2-EF5) tornadoes

Low (10%)

WindProbability of 10 or more severe wind events

Mod (50%)

Probability of 1 or more wind events > 65 knots

Mod (30%)

HailProbability of 10 or more severe hail events

Low ( 2 inches

Low (

SPC Severe Thunderstorm Watch 529 Status Reports

Source: US National Oceanic and Atmospheric Administration

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Watch 529 Status Reports

Watch 529 Status Message has not been issued yet.

Top/Watch Issuance Text for Watch 529/All Current Watches/Forecast Products/Home

Weather Topics:Watches, Mesoscale Discussions, Outlooks, Fire Weather, All Products, Contact Us

NOAA / National Weather ServiceNational Centers for Environmental PredictionStorm Prediction Center120 David L. Boren Blvd.Norman, OK 73072 U.S.A.spc.feedback@noaa.govPage last modified: October 16, 2021
DisclaimerInformation QualityHelpGlossary
Privacy PolicyFreedom of Information Act (FOIA)About UsCareer Opportunities

SPC MD 1870

Source: US National Oceanic and Atmospheric Administration

Mesoscale Discussion 1870

Mesoscale Discussion 1870
NWS Storm Prediction Center Norman OK
1006 AM CDT Sat Oct 16 2021

Areas affected…Central/Eastern PA…South-Central NY

Concerning…Severe potential…Watch possible

Valid 161506Z – 161700Z

Probability of Watch Issuance…60 percent

SUMMARY…A narrow line of stronger storms is expected to move
northeastward into more of eastern PA and south-central NY over the
next few hours. Convective trends will be monitored for possible
watch issuance.

DISCUSSION…Recent radar trends show increasing reflectivity within
the line of showers and thunderstorms just ahead of the front in
central PA. Recent lightning data shows an increasing trend in
flashes within this line as well. This matches forecast expectations
with storms expected to gradual strengthen amid continued lift along
the front, increasing large-scale forcing for ascent, and modest
diurnal destabilization.

Low to mid-level flow is also strengthening across the region, shown
well by the BGM VAD, which recently sampled 45-50 kt at 1 km AGL
increasing to 60 kt between 2-3 km AGL. The resulting vertical
profile had 0-1 km bulk shear around 35 kt and 0-1 km storm-relative
helicity near 250 m2/s2.

The resulting combination of ascent, modest buoyancy, and strong
vertical shear is forecast to result in a narrow line of deeper
convection capable of producing damaging wind gusts and maybe even a
brief embedded tornado or two as it moves northeastward.

..Mosier/Grams.. 10/16/2021

…Please see www.spc.noaa.gov for graphic product…

ATTN…WFO…ALY…PHI…BGM…CTP…

LAT…LON 41547731 42467639 43167557 42797445 41897459 39917606
40107789 41547731

Top/All Mesoscale Discussions/Forecast Products/Home

SPC Oct 16, 2021 1300 UTC Day 1 Convective Outlook

Source: US National Oceanic and Atmospheric Administration

SPC AC 161252

Day 1 Convective Outlook
NWS Storm Prediction Center Norman OK
0752 AM CDT Sat Oct 16 2021

Valid 161300Z – 171200Z

…THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS OVER PORTIONS OF
THE MID-ATLANTIC AND NEW ENGLAND…

…SUMMARY…
Damaging to severe thunderstorm gusts and a marginal tornado threat
are possible through the afternoon over portions of the Mid-Atlantic
and New England.

…Synopsis…
A highly amplified — yet still progressive — mid/upper-level
pattern will affect the CONUS through the period. A deep trough —
initially located from far northern ON across the upper Great Lakes
to AR — will shift eastward to western QC, the inland Mid-Atlantic,
the Carolinas, and GA by the end of the period. As this occurs, the
basal shortwave trough — apparent in moisture-channel imagery from
western OH to the Mid-South — will pivot northeastward and
accelerate, reaching Lake Ontario, central PA and central VA by 00Z.
This perturbation then will eject northeastward across QC and New
England overnight while weakening, and while other, trailing
shortwaves move through the base of the larger-scale trough.
Synoptic ridging will cross the Rockies, while a sharp trough
approaches the Pacific Northwest (but still offshore at 12Z
tomorrow).

At the surface, 11Z analysis showed a cold front from Lake Ontario
across western NY, northwestern PA, WV, southwestern VA, to southern
AL and the northwestern Gulf. By 00Z, the front should reach
western New England, coastal NJ/Delmarva, the eastern Carolinas, and
northern FL. By 12Z, the cold front should be over CONUS land only
in ME and central FL, offshore elsewhere.

…Portions of the Mid-Atlantic and New England…
A low-CAPE/strong-shear convective event is expected in the
Northeast today, with the delineation between threat categories
realistically fuzzier than can be depicted by a sharp categorical
contour line on a map. A frontal/prefrontal band of thick clouds
and precip, with isolated embedded thunderstorms, is ongoing from
portions of northern/western NY and Lake Ontario across western PA
and WV to northeastern TN. Through the remainder of the morning and
into early afternoon, convective organization and coverage each
should grow, with a gradual increase of the severe-wind and tornado
threat from initially marginal and very isolated nature now.

The convective band will encounter a warm sector undergoing gradual
destabilization, from both theta-e advection and muted diabatic
heating. This will help to reduce already weak MLCINH and offset
modest mid/upper-level lapse rates just enough to support peak/
preconvective MLCAPE of 250-750 J/kg. Very long and somewhat curved
low-level hodographs — larger with northward extent — may lead to
0-1-km and effective SRH each in the 150-250 J/kg range, amidst
effective-shear magnitudes ranging from 45-50 kt in southern parts
of the outlook to 55-60 kt in the north. This will support some
storm-scale rotation — be it discrete to semi-discrete supercells
or line-embedded mesovortices. Overall severe potential should wane
this evening as already weak low-level instability diminishes
further.

..Edwards/Leitman.. 10/16/2021

CLICK TO GET WUUS01 PTSDY1 PRODUCT

NOTE: THE NEXT DAY 1 OUTLOOK IS SCHEDULED BY 1630Z