RSS Mesoscale Discussions from Storm Prediction Center
No watches are valid as of Tue May 5 17:56:02 UTC 2026.
MD 0645 CONCERNING SEVERE POTENTIAL...WATCH UNLIKELY FOR PORTIONS OF CENTRAL NEW YORK INTO WESTERN MASSACHUSETTS...VERMONT...NEW HAMPSHIRE...AND WESTERN MAINE
Mesoscale Discussion 0645
NWS Storm Prediction Center Norman OK
1233 PM CDT Tue May 05 2026
Areas affected...portions of central New York into western
Massachusetts...Vermont...New Hampshire...and western Maine
Concerning...Severe potential...Watch unlikely
Valid 051733Z - 051900Z
Probability of Watch Issuance...20 percent
SUMMARY...An uptick in thunderstorm coverage is expected this
afternoon. Damaging gusts will be the main threat with the stronger
storms, though an instance of hail or a brief tornado could occur.
The severe threat seems isolated, so a WW issuance is not currently
expected.
DISCUSSION...Adequate surface heating ahead of an approaching cold
front (currently over eastern Ontario) has allowed for boundary
layer destabilization, amid diminishing MLCINH, to support
convective initiation over portions of upstate NY. Ahead of these
storms, surface temperatures exceeding 80 F, despite meager
low-level moisture (45-50 F surface dewpoints) and poor mid-level
lapse rates, is resulting in 500-1000 J/kg SBCAPE. Parallel
deep-layer flow to the approaching cold front suggests that
predominantly linear storm modes are expected. Given 8-9 C/km
boundary layer lapse rates, efficient downward momentum transport
potential will exist for damaging gusts, though an instance of hail
or a brief tornado may occur if a robust, discrete storm could
develop. Nonetheless, the overall severe threat should be sparse, so
a WW issuance is not anticipated.
..Squitieri/Smith.. 05/05/2026
...Please see www.spc.noaa.gov for graphic product...
ATTN...WFO...CAR...GYX...BOX...BTV...ALY...BGM...BUF...
LAT...LON 43187620 44547468 45117234 45517078 45567004 45346969
44776987 44007077 43227208 42657272 42347340 42287426
42187532 42287606 43187620
MOST PROBABLE PEAK TORNADO INTENSITY...UP TO 90 MPH
MOST PROBABLE PEAK WIND GUST...UP TO 60 MPH
MOST PROBABLE PEAK HAIL SIZE...UP TO 1.25 IN
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SPC 1630Z Day 1 Outlook
Day 1 Convective Outlook
NWS Storm Prediction Center Norman OK
1131 AM CDT Tue May 05 2026
Valid 051630Z - 061200Z
...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS CENTERED OVER
ARKANSAS AND EXTENDING FROM NORTHEAST TEXAS INTO WESTERN
TENNESSEE...
...SUMMARY...
Widely scattered severe storms are possible this afternoon through
this evening from north Texas, much of Arkansas, and into western
Tennessee. Large to very large hail, severe gusts, and a few
tornadoes are possible.
...Northeast TX into the Mid-South...
Radar mosaic shows an MCV moving east across far western KY with a
band of weak thunderstorms extending south and west across western
TN. Convective outflow associated with the showers/thunderstorms
extends from east-west near I-40 across AR into eastern OK where it
intersects a triple point over central OK. A cold front is draped
southwest to northeast along the I-44 corridor from western north TX
northeastward into the Ozarks.
Visible-satellite imagery late this morning shows extensive cloud
cover from northeast TX northeastward into AR and the lower OH
Valley. A plume of richer moisture at the surface is denoted by mid
to upper 60s deg F dewpoints protruding north from east-central TX
into north TX and southeast OK. Further moistening of low levels
via southerly return flow is forecast beneath a capping inversion
around 850 mb sampled by the 12 UTC Forth Worth, TX raob.
Gradual boundary layer heating will result in surface temperatures
warming into the upper 80s over north TX with muted heating farther
northeast over AR where persistent cloud cover will inhibit stronger
heating. Model guidance shows MLCAPE ranging from 500-1500 J/kg
from northeast AR southwestward into southwest AR, and upwards of
3000 J/kg MLCAPE across north TX by mid-late afternoon. Convergence
along the front will be modest and large-scale height rises are
anticipated. However, thinning clouds near the OK/AR border and the
erosion of convective inhibition as convective temperatures are
breached over north TX will result in isolated to scattered storms
developing during 20-23 UTC period. Initial supercell mode is
forecast over north TX with some clustering expected during the
evening. The tornado risk over north TX will likely be limited by
relatively weak low-level shear but strong mid to high-level flow
will promote large to very large hail growth (1 to 3 inches in
diameter). Farther northeast, isolated to scattered storms are
forecast to develop east of the eastward-migrating surface low and
near the front by the mid-late afternoon. HRRR time-lagged runs
this morning show a few supercells with one more longer track storms
moving developing and moving east across central AR in a larger SRH
environment. An all hazards severe risk may accompany the stronger
storms in AR beginning later this afternoon and possibly persisting
through the evening as this activity moves east towards the MS
River. A strong tornado is possible with a sustained discrete
supercell. Upscale growth into a cluster or band of storms is
expected as moderately strong southwesterly 850 to 700-mb flow is
maintained across the Mid South. Damaging gusts and perhaps a
lingering tornado risk will possibly spread east tonight before
storms weaken late.
...Lower Great Lakes into northern New England...
A marginally moist airmass will advect northeastward into the Lower
Great Lakes and Northeast ahead of an eastward-moving cold front,
with low 50s dewpoints likely reaching as far north as ME. This
low-level moisture coupled with afternoon temperatures in the 70s
will support modest buoyancy, despite poor lapse rates.
Thunderstorms are anticipated along and ahead of the
eastward-progressing front as it moves into the destabilized airmass
from the Lower Great Lakes into northern ME.
Strong deep-layer vertical will be in place, supported by relatively
deep southwesterly flow, suggesting the potential for organized
storms. However, this flow will be largely parallel to the
boundary, with linear structures favored. Damaging gusts will be
possible with the strongest storms, although transient updraft
strength should keep the overall coverage and intensity modest.
Isolated hail is possible with a few storms as well. Predominantly
linear mode should keep the tornado risk low, although a
low-probability threat still exists, particularly if a pocket of
strong buoyancy can develop across Upstate NY.
..Smith/Squitieri.. 05/05/2026
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SPC 1730Z Day 2 Outlook
Day 2 Convective Outlook
NWS Storm Prediction Center Norman OK
1245 PM CDT Tue May 05 2026
Valid 061200Z - 071200Z
...THERE IS AN ENHANCED RISK OF SEVERE THUNDERSTORMS FROM NORTHERN
LOUISIANA ARCROSS PARTS OF MISSISSIPPI AND ALABAMA...
...SUMMARY...
Scattered severe thunderstorms are expected Wednesday afternoon and
evening from eastern Texas into the lower Mississippi and Tennessee
Valleys/southern Appalachians. Tornadoes appear most likely from
Mississippi into Alabama. Corridors of damaging winds may occur from
Texas into Georgia.
...Synopsis...
Strong mid to high level winds will intensify across the MS/OH/TN
Valleys on Wednesday as a positive-tilt upper trough moves out of
the Plains. Midlevel winds up to 50 kt will extend as far south as
the Gulf Coast, with 70+ kt sweeping across the TN Valley to the
Appalachians late.
At the surface, a cold front will extend from central TX into
northern MS and AL by 00Z, with a very moist air mass ahead of it.
Dewpoints in the 70s F will be common from TX into MS, with mid 60s
F into western GA by evening. Instability will be greatest from TX
into MS during the day, but will develop eastward across AL and into
western GA due to persistent west/southwest winds in the low levels.
The expansive area of strong deep-layer shear atop the very moist
air mass will support scattered to widespread thunderstorms
beginning late afternoon and spreading during the evening and
overnight. Corridors of tornado and wind damage potential appear
likely, with hail from TX into LA/MS.
...Eastern TX across much of the Southeast...
Early day storms are possible across TN and into northern MS/AL/GA,
possibly elevated due to and e-w outflow. A marginal wind threat
cannot be ruled out at that time.
The primary severe risk will develop during the late afternoon after
21Z and into the early evening, as instability builds. Supercells
may develop along and ahead of the cold front. The deep moist layer
combined with strong mid and high level flow should support
supercell mode with minimal cold downdraft initially. The severe
risk may persist during the evening into GA as the southwesterly
low-level jet brings instability into that area. Corridors of
damaging winds may evolve as well, especially along the cold front
late as storms become more numerous.
Farther west into TX, supercells producing hail and locally damaging
gusts are also likely near the front.
..Jewell.. 05/05/2026
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SPC Day 1 Fire Weather Outlook
Day 1 Fire Weather Outlook
NWS Storm Prediction Center Norman OK
1147 AM CDT Tue May 05 2026
Valid 051700Z - 061200Z
...Morning Update...
The previous forecast remains on track. Across portions of the
Mid-Atlantic, clear skies this morning and poor overnight recoveries
have resulted in widespread RH values of 25-40 percent. In parts of
southeastern NM and West Texas, mostly cloudy skies will remain over
the area as the subtropical jet transports mid-high level moisture
overhead. Surface troughing in the lee of the NM high terrain
through far West TX will align with low level thermal ridging,
promoting warm afternoon temperatures and gusty westerly winds.
Widespread gusts of up to 35 mph appear likely throughout the
Plains, with locally higher gusts possible (especially along the
higher terrain). However, a tempered fuelscape due to recent
rainfall mitigates a broader fire threat.
..Elizalde-Garcia.. 05/05/2026
.PREV DISCUSSION... /ISSUED 1255 AM CDT Tue May 05 2026/
...Synopsis...
Stronger southwesterly flow aloft ahead of an advancing upper-level
trough will move into the Southern Plains through today. A cold
front trailing behind an elongated surface low over OK should stall
across the TX Panhandle and just south of the Red River Valley this
afternoon. Farther east, a deepening upper trough over Ontario and
Quebec and associated increasing southwesterly mid-level flow will
encroach into the Northeast today. At the surface, drier pre-frontal
southwest flow will affect much of the Mid Atlantic and Northeast.
...Mid Atlantic...
Dry, southerly to southwesterly flow ahead of an eastward moving
cold front across the OH River Valley is expected across the Mid
Atlantic today. Limited boundary layer moisture, leading to RH
reductions of 20-30%, and sustained south/southwest winds of around
15 mph with higher gusts will evolve by mid-afternoon in the
Carolinas and Mid Atlantic. A zone of minimal rainfall has resulted
in lingering fuel dryness across northern NC into much of central
and eastern VA. Elevated fire weather highlights where added to the
aforementioned area where most likely alignment of dry and breezy
conditions and dry fuels exist.
...West Texas...
A 60-65 knot mid-level jet in advance of an upper trough will eject
into the Southern Plains today. A cold front will stall across the
northwest TX, inhibiting dry, downslope enhanced westerly flow from
aligning with the more receptive fuels across the eastern TX
Panhandle into southwestern KS. Breezy west winds of 15-25 mph amid
relative humidity of around 15% are still expected across much of
west TX. However, recent wetting rainfall in the region has
mitigated the overall fuelscape, limiting impact from an otherwise
elevated fire weather threat.
...Please see www.spc.noaa.gov/fire for graphic product...
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