RSS Mesoscale Discussions from Storm Prediction Center
No watches are valid as of Tue Jul 14 22:56:02 UTC 2026.
MD 1616 CONCERNING SEVERE POTENTIAL...WATCH POSSIBLE FOR PORTIONS OF NORTHERN NEW YORK...VERMONT...NEW HAMPSHIRE AND SOUTHWEST MAINE
Mesoscale Discussion 1616
NWS Storm Prediction Center Norman OK
0553 PM CDT Tue Jul 14 2026
Areas affected...portions of northern New York...Vermont...New
Hampshire and southwest Maine
Concerning...Severe potential...Watch possible
Valid 142253Z - 150100Z
Probability of Watch Issuance...40 percent
SUMMARY...Severe potential remains evident over parts of New England
through this evening, both with ongoing storms and new convective
development in southern Quebec. The need for a watch is unclear, but
trends are being watched closely.
DISCUSSION...As of 2250 UTC, regional visible and radar imagery
showed a cluster of thunderstorms in northern NH and southwest ME
have remained generally weak. Widespread wildfire smoke and cloud
debris has limited diurnal heating, resulting in lingering
inhibition evident from terrain-induced stable billow clouds over
portions of southern New England. However, just to the south of the
primary baroclinic zone, a much warmer air mass remains relatively
undisturbed this evening. With MLCAPE of 2000-3000 J/kg and ample
vertical shear, intensification of the ongoing storms remains
possible if they are able to access the more unstable air mass. A
mix of organized clusters and supercells would present some risk for
all hazards.
Meanwhile, a second cluster of storms is evident over portions of
southern QC, along with more agitated boundary-layer cumulus near
the international border. HRRR guidance continues to show some
intensification/additional development with this cluster through
this evening. This is plausible given the proximity to the warmer
and more unstable air mass along and southeast of the St Lawrence
Valley. The approach of the upper trough and strong mid-level jet
(70+ kt) may also provide enough ascent to overcome the remaining
inhibition in the next couple of hours. However, confidence in the
convective evolution remains very low. All hazards would be possible
if this cluster, or any new development can intensify.
The environment remains conditionally supportive of organized
clusters and supercells with significant severe potential.
Convective trends are being closely monitored, but the need for a WW
remains unclear.
..Lyons/Smith.. 07/14/2026
...Please see www.spc.noaa.gov for graphic product...
ATTN...WFO...GYX...BTV...
LAT...LON 45357481 45537201 45557132 45017026 44737008 44387004
44007037 43937105 44337389 44537446 44677477 44887493
45357481
MOST PROBABLE PEAK TORNADO INTENSITY...100-125 MPH
MOST PROBABLE PEAK WIND GUST...55-70 MPH
MOST PROBABLE PEAK HAIL SIZE...1.50-2.50 IN
Read more
MD 1615 CONCERNING SEVERE POTENTIAL...WATCH POSSIBLE FOR PORTIONS OF CENTRAL MONTANA
Mesoscale Discussion 1615
NWS Storm Prediction Center Norman OK
0522 PM CDT Tue Jul 14 2026
Areas affected...portions of central Montana
Concerning...Severe potential...Watch possible
Valid 142222Z - 142345Z
Probability of Watch Issuance...60 percent
SUMMARY...Scattered thunderstorms should develop over the next few
hours, posing a severe gust threat. A WW issuance may be needed
pending greater storm coverage.
DISCUSSION...Hints at convective initiation (via the detection of
lightning with NLDN data) are underway along the eastern fringe of a
cloud shield overspreading the northern Rockies in association with
a 500 mb wind maximum grazing central MT. Here, surface temperatures
are approaching 95 F amid mid 50s to lower 60s F surface dewpoints,
yielding over 1000 J/kg MLCAPE. 30+ F surface temperature/dewpoint
spreads are in place, with RAP forecast soundings showing an
appreciably mixed boundary layer extending up to at least 700 mb. As
such, if the mixing boundary layer can support the initiation of
additional storms over the next few hours, evaporative cooling
potential should be sufficient to support severe gusts with the
heavier storm cores. An instance or two of severe hail also cannot
be ruled out. A Severe Thunderstorm Watch issuance may be needed
if/when greater storm coverage becomes clearer.
..Squitieri/Smith.. 07/14/2026
...Please see www.spc.noaa.gov for graphic product...
ATTN...WFO...BYZ...GGW...TFX...
LAT...LON 46091177 47001101 47641022 48130872 48250737 48170675
47750636 47000670 46340787 45720877 45500930 45410989
45331073 46091177
MOST PROBABLE PEAK WIND GUST...65-80 MPH
MOST PROBABLE PEAK HAIL SIZE...UP TO 1.25 IN
Read more
SPC 2000Z Day 1 Outlook
Day 1 Convective Outlook
NWS Storm Prediction Center Norman OK
0249 PM CDT Tue Jul 14 2026
Valid 142000Z - 151200Z
...THERE IS AN ENHANCED RISK OF SEVERE THUNDERSTORMS ACROSS PORTIONS
OF THE NORTHEAST...
...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS ACROSS CENTRAL
MONTANA...
...SUMMARY...
Severe thunderstorms capable of producing damaging winds, large
hail, and a few tornadoes are expected today across parts of
northern New York and New England. Thunderstorms with scattered
severe winds and isolated hail will also be possible across portions
of Montana.
...20z Update...
The previous forecast largely remains on track with only minor
adjustments required. Convection across southeast Quebec has
struggled to maintained intensity as it approaches the U.S. border
through mid-afternoon with abundant cirrus, smoke, and cloud debris
overspreading central to northern ME. Recent surface observations
show temperatures remaining in the mid/upper 70s, which is
supporting very limited MLCAPE per the 18 UTC CAR RAOB. This casts
considerable uncertainty on the degree of destabilization that will
occur through the early evening hours. Latest CAM guidance appears
to be capturing this trend and depicts low probabilities for intense
UH and/or strong wind swaths across northern ME. 30%/Enhanced
contours were trimmed southward to account for this decreased
confidence.
Further southwest, warmer temperatures in the 80s are supporting a
more volatile atmosphere with MLCAPE values estimated to be around
2000 J/kg. Strong shear remains across the region per VWP
observations, and CAM guidance continues to depict some potential
for intense convection traversing northern NY, VT, NH and western ME
later this evening as the primary surface trough migrates east. Risk
probabilities have been shifted southwest to better align with the
better thermodynamic environment and convective signal. However, the
recent convective trends upstream and modulating influence of
wildfire smoke on boundary-layer mixing/CIN reduction casts
uncertainty on how widespread the severe threat may be.
...Florida...
Regional reflectivity and velocity data shows a few stronger
thunderstorms developing across the FL Peninsula with occasional
downbursts. Further heating over the next few hours will continue to
support some potential for strong/severe downburst winds. See MCD
#1614 for additional information.
...Montana...
Deepening cumulus is noted within the higher terrain of southern MT
and western WY as temperatures warm into the upper 80s and low 90s.
Guidance continues to show reasonably strong agreement in the
emergence of one or more clusters across the region through
mid-evening that will pose a risk of large hail and severe gusts.
With low-level lapse rates increasing to around 8 C/km and 30-40
knots of effective shear in place, there is some potential for
sporadic wind gusts upwards of 65-75 mph. This potential is
highlighted by recent CAM ensembles, and warranted introducing a CIG
level 1 area across parts of central MT where thermodynamic
conditions should be most favorable through early evening.
..Moore.. 07/14/2026
.PREV DISCUSSION... /ISSUED 1115 AM CDT Tue Jul 14 2026/
...New England...
Morning water vapor imagery shows a belt of 80+ knot mid level winds
nosing from eastern Ontario into Quebec, with mid-level height falls
and large-scale forcing spreading into northern New England. This
has been aiding in multiple rounds of intense thunderstorms over
Quebec this morning, but so far this activity has struggled to make
it into the US due to a more stable air mass. This will change
through the day as a moist and moderately unstable air mass advects
eastward into parts of New England ahead of the primary convective
activity. Widespread smoke from upstream fires will also somewhat
limit daytime heating today, although the extent of the cooling is
uncertain.
Present indications are that several convective cells and clusters
will track southeastward across parts of eastern NY, VT/NH and
western ME later this afternoon and evening. Forecast soundings in
this region show favorable CAPE/shear combinations for supercell
storms capable of damaging winds, large hail, and a few tornadoes.
Larger bowing clusters may also evolve, with a greater risk of
damaging winds. This activity may persist after midnight with a
continued severe risk.
...MT...
A shortwave trough now over NV and its associated mid-level speed
max will rotate northward into parts of ID/MT this afternoon and
evening, aiding in the development of thunderstorms over the
mountains. Storms are expected to spread northeastward into the
Plains during the evening, with a risk of severe wind gusts in the
strongest storms.
...FL...
Hot and humid conditions will lead to strong afternoon CAPE values
and scattered thunderstorms over the central FL peninsula. Forecast
soundings show slightly enhanced westerly flow around 700mb across
this area, which may aid in occasionally damaging winds in the
stronger cores.
Read more
SPC 1930Z Day 3 Outlook
Day 3 Convective Outlook
NWS Storm Prediction Center Norman OK
0227 PM CDT Tue Jul 14 2026
Valid 161200Z - 171200Z
...NO SEVERE THUNDERSTORM AREAS FORECAST...
...SUMMARY...
Organized severe thunderstorms are currently not expected on
Thursday.
...Synopsis...
A deep-layer cyclone is expected to remain in place over parts of
Labrador and northern Quebec on Thursday. A vigorous mid/upper-level
shortwave is forecast to move through the base of the attendant
trough across parts of northern New England. To the west, a
mid/upper-level cyclone off of the Pacific Northwest coast is
forecast to move north-northeastward toward Vancouver Island.
Farther south, a persistent mid/upper-level trough will continue to
bring a threat of widespread convection and heavy rainfall across
parts of southwest TX and vicinity. Thunderstorm potential will
cover a large part of the CONUS, though generally weak
mid/upper-level flow should limit potential for organized convection
across most areas.
...Northern New England...
A strong reinforcing front will accompany the mid/upper shortwave
moving across northern New England on Thursday. Guidance varies
considerably regarding the extent of heating and destabilization
along/ahead of this front. The more aggressive guidance (such as the
NAM NEST and RRFS) depicts MLCAPE increasing to near/above 500 J/kg,
sufficient for organized convection given the strength of the
low-midlevel wind fields. Other guidance depicts very limited
destabilization and severe potential. Depending on trends regarding
destabilization and timing of the front, severe probabilities may
eventually be needed.
...Mid-Atlantic...
While large-scale ascent will generally be weak, strong heating in
the vicinity of a remnant frontal zone may allow for isolated storm
development across parts of the Mid-Atlantic and vicinity on
Thursday. Low-level flow will be weak and deep-layer shear will be
modest at best, but localized strong/damaging gusts could occur, if
sustained storms develop within this hot and well-mixed regime.
...Interior Northwest...
While the magnitude of diurnal destabilization across parts of the
interior Northwest remains uncertain, some potential for
strong-storm development could evolve as stronger mid/upper-level
flow associated with the offshore low overspreads the region. This
area will continue to be monitored regarding the need for severe
probabilities.
..Dean.. 07/14/2026
Read more
SPC Day 2 Fire Weather Outlook
Day 2 Fire Weather Outlook
NWS Storm Prediction Center Norman OK
0207 PM CDT Tue Jul 14 2026
Valid 151200Z - 161200Z
...Afternoon Update...
An Isolated Dry Thunderstorm risk area was introduced across the
Cascades and central-eastern OR/WA. As a shortwave trough impinges
upon the Pacific Northwest, strong south-southwesterly flow aloft
will blanket the region. Orographic ascent and daytime instability
amid residual mid-level moisture will support mixed wet/dry
thunderstorms on Day 2/Wednesday afternoon and evening. Forecast
soundings depict 0.7-1.0" PWATs, 300-600 J/kg MUCAPE, and 7.5-8 C/km
700-500 mb lapse rates. While some thunderstorms will be capable of
locally heavier rainfall, greater precipitation efficiency will
likely be limited given strong LCL-EL winds of 20-30 kts and a dry
boundary layer favoring evaporation. A Fuels & Fire Behavior
Advisory was issued this morning (Day 1/Tuesday) across portions of
the Pacific Northwest, encompassing some of the IsoDryT risk area,
denoting worsening region-wide drought has contributed to a very dry
fuelscape and stressed vegetation. Lightning ignitions are possible
given the state of dry fuels, and gusty/erratic winds could further
exacerbate any new and ongoing wildfires.
The Elevated fire weather risk area was expanded to include more of
the Central Valley into the Transverse Ranges where
west-northwesterly winds of 10-15 mph (locally higher) and 15-20% RH
values will overlap drying fuels.
The rest of the forecast remains on track, see the previous
discussion for more information.
..Elizalde-Garcia.. 07/14/2026
.PREV DISCUSSION... /ISSUED 1255 AM CDT Tue Jul 14 2026/
...Synopsis...
An expansive mid-level ridge will remain over the central U.S. as a
surface trough lingers across the northern Plains, bringing another
day of fire weather concerns to parts of the northern High Plains
via dry and breezy conditions. Gusty onshore winds across the
California Coastal Ranges into the Central Valley will promote a
fire weather threat Wednesday as fuels continue to dry.
...Central California Coastal Ranges and Central Valley...
Onshore flow aided by downslope drying and terrain accelerated winds
will support elevated fire weather conditions across the central CA
coastal ranges into the adjacent Central Valley. Fuels continue to
dry with ERC values reaching the 90-95th percentile range under very
warm temperatures. These winds generally from the west and northwest
at 10-15 mph (locally 20-25 mph in favored terrain gaps) combined
with RH of 15-20% in the coastal ranges to as low as 10% in the
Central valley, will support elevated fire weather conditions
Wednesday afternoon and early evening.
...Northern High Plains...
Hot and dry conditions under a stagnant mid-level ridge over the
central U.S. are expected across portions of the northern Plains
Wednesday. At the surface, a trough over southeastern MT will
bolster low-level southeasterly flow (up to 15 mph sustained) over
portions of western SD, NE Panhandle and northern CO. These winds
coinciding with RH in the 15-20% range will yield elevated fire
weather conditions amid very dry fuels Wednesday afternoon. Elevated
highlights were extended into central WY given latest forecast
guidance with expected RH as low as 10 percent and steady easterly
winds.
...Please see www.spc.noaa.gov/fire for graphic product...
Read more
SPC Day 3-8 Fire Weather Outlook
Day 3-8 Fire Weather Outlook
NWS Storm Prediction Center Norman OK
0437 PM CDT Tue Jul 14 2026
Valid 161200Z - 221200Z
...Synopsis...
A strong upper ridge will persist over the central/northern Plains
through the end of this week into the early weekend. Following a
northward progressing shortwave trough along the Pacific Northwest
coast on Day 3/Thursday, ensembles indicate the upper ridge will
then translate westward to encompass much of the western CONUS while
the eastern US is expected to remain in a troughing pattern. Daily
chances of thunderstorm activity are possible in the extended
forecast period across the Intermountain West as monsoonal moisture
advects northward once again.
...Portions of northeastern California and the Central Valley,
northwestern Nevada, and far south-central Oregon...
Warm daytime temperatures and low RH will contribute to drying fuels
across the California Coastal Ranges into the Central Valley. ERCs
are forecast to approach the 90-95th percentile by late this week
amid dry and breezy conditions, supporting any new ignitions and the
emergence of lightning holdovers from wet/dry thunderstorms early in
the forecast period. 40% Critical probabilities remain on Day
3/Thursday to account for this threat. Farther north, strong
south-southwesterly flow aloft behind a shortwave trough bypassing
the Pacific Northwest will encourage dry and windy conditions across
northeastern California, northwestern Nevada, and south-central
Oregon on Days 3-4/Thursday-Friday. Preceding days of thunderstorms
and pockets of heavier rainfall may alleviate some fuel concerns;
however, a returning dry airmass and gusty winds may encourage any
lightning holdovers to emerge.
..Elizalde-Garcia.. 07/14/2026
...Please see www.spc.noaa.gov/fire for graphic product...
Read more
|
